Search results for: functional expression
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4657

Search results for: functional expression

4507 HLA-G, a Neglected Immunosuppressive Checkpoint for Breast Cancer Immunotherapy

Authors: Xian-Peng Jiang, Catherine C. Baucom, Toby Jiang, Robert L. Elliott

Abstract:

HLA-G binds to the inhibitory receptors of uterine NK cells and plays an important role in protection of fetal cells from maternal NK lysis. HLA-G also mediates tumor escape, but the immunosuppressive role is often neglected. These studies have focused on the examination of HLA-G expression in human breast carcinoma and HLA-G immunosuppressive role in NK cytolysis. We examined HLA-G expression in breast cell lines by real time PCR, ELISA and immunofluorescent staining. We treated the breast cancer cell lines with anti-human HLA-G antibody or progesterone. Then, NK cytolysis was measured by using MTT assay. We find that breast carcinoma cell lines increase the expression of HLA-G mRNA and protein, compared to normal cells. Blocking HLA-G of the breast cancer cells by the antibody increases NK cytolysis. Progesterone upregulates HLA-G mRNA and protein of human breast cancer cell lines. The increased HLA-G expression suppresses NK cytolysis. In summary, human breast carcinoma overexpress HLA-G immunosuppressive molecules. Blocking HLA-G protein by antibody improves NK cytolysis. In contrast, upregulation of HLA-G expression by progesterone impairs NK cytolytic function. Thus, HLA-G is a new immunosuppressive checkpoint and potential cancer immunotherapeutic target.

Keywords: HLA-G, Breast carcinoma, NK cells, Immunosuppressive checkpoint

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4506 Cloning and Expression of Human Interleukin 15: A Promising Candidate for Cytokine Immunotherapy

Authors: Sadaf Ilyas

Abstract:

Recombinant cytokines have been employed successfully as potential therapeutic agent. Some cytokine therapies are already used as a part of clinical practice, ranging from early exploratory trials to well established therapies that have already received approval. Interleukin 15 is a pleiotropic cytokine having multiple roles in peripheral innate and adaptive immune cell function. It regulates the activation, proliferation and maturation of NK cells, T-cells, monocytes/macrophages and granulocytes, and the interactions between them thus acting as a bridge between innate and adaptive immune responses. Unraveling the biology of IL-15 has revealed some interesting surprises that may point toward some of the first therapeutic applications for this cytokine. In this study, the human interleukin 15 gene was isolated, amplified and ligated to a TA vector which was then transfected to a bacterial host, E. coli Top10F’. The sequence of cloned gene was confirmed and it showed 100% homology with the reported sequence. The confirmed gene was then subcloned in pET Expression system to study the IPTG induced expression of IL-15 gene. Positive expression was obtained for number of clones that showed 15 kd band of IL-15 in SDS-PAGE analysis, indicating the successful strain development that can be studied further to assess the potential therapeutic intervention of this cytokine in relevance to human diseases.

Keywords: Interleukin 15, pET expression system, immune therapy, protein purification

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4505 Robustness Conditions for the Establishment of Stationary Patterns of Drosophila Segmentation Gene Expression

Authors: Ekaterina M. Myasnikova, Andrey A. Makashov, Alexander V. Spirov

Abstract:

First manifestation of a segmentation pattern in the early Drosophila development is the formation of expression domains (along with the main embryo axis) of genes belonging to the trunk gene class. Highly variable expression of genes from gap family in early Drosophila embryo is strongly reduced by the start of gastrulation due to the gene cross-regulation. The dynamics of gene expression is described by a gene circuit model for a system of four gap genes. It is shown that for the formation of a steep and stationary border by the model it is necessary that there existed a nucleus (modeling point) in which the gene expression level is constant in time and hence is described by a stationary equation. All the rest genes expressed in this nucleus are in a dynamic equilibrium. The mechanism of border formation associated with the existence of a stationary nucleus is also confirmed by the experiment. An important advantage of this approach is that properties of the system in a stationary nucleus are described by algebraic equations and can be easily handled analytically. Thus we explicitly characterize the cross-regulation properties necessary for the robustness and formulate the conditions providing this effect through the properties of the initial input data. It is shown that our formally derived conditions are satisfied for the previously published model solutions.

Keywords: drosophila, gap genes, reaction-diffusion model, robustness

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4504 Systematic Identification of Noncoding Cancer Driver Somatic Mutations

Authors: Zohar Manber, Ran Elkon

Abstract:

Accumulation of somatic mutations (SMs) in the genome is a major driving force of cancer development. Most SMs in the tumor's genome are functionally neutral; however, some cause damage to critical processes and provide the tumor with a selective growth advantage (termed cancer driver mutations). Current research on functional significance of SMs is mainly focused on finding alterations in protein coding sequences. However, the exome comprises only 3% of the human genome, and thus, SMs in the noncoding genome significantly outnumber those that map to protein-coding regions. Although our understanding of noncoding driver SMs is very rudimentary, it is likely that disruption of regulatory elements in the genome is an important, yet largely underexplored mechanism by which somatic mutations contribute to cancer development. The expression of most human genes is controlled by multiple enhancers, and therefore, it is conceivable that regulatory SMs are distributed across different enhancers of the same target gene. Yet, to date, most statistical searches for regulatory SMs have considered each regulatory element individually, which may reduce statistical power. The first challenge in considering the cumulative activity of all the enhancers of a gene as a single unit is to map enhancers to their target promoters. Such mapping defines for each gene its set of regulating enhancers (termed "set of regulatory elements" (SRE)). Considering multiple enhancers of each gene as one unit holds great promise for enhancing the identification of driver regulatory SMs. However, the success of this approach is greatly dependent on the availability of comprehensive and accurate enhancer-promoter (E-P) maps. To date, the discovery of driver regulatory SMs has been hindered by insufficient sample sizes and statistical analyses that often considered each regulatory element separately. In this study, we analyzed more than 2,500 whole-genome sequence (WGS) samples provided by The Cancer Genome Atlas (TCGA) and The International Cancer Genome Consortium (ICGC) in order to identify such driver regulatory SMs. Our analyses took into account the combinatorial aspect of gene regulation by considering all the enhancers that control the same target gene as one unit, based on E-P maps from three genomics resources. The identification of candidate driver noncoding SMs is based on their recurrence. We searched for SREs of genes that are "hotspots" for SMs (that is, they accumulate SMs at a significantly elevated rate). To test the statistical significance of recurrence of SMs within a gene's SRE, we used both global and local background mutation rates. Using this approach, we detected - in seven different cancer types - numerous "hotspots" for SMs. To support the functional significance of these recurrent noncoding SMs, we further examined their association with the expression level of their target gene (using gene expression data provided by the ICGC and TCGA for samples that were also analyzed by WGS).

Keywords: cancer genomics, enhancers, noncoding genome, regulatory elements

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4503 Investigate the Side Effects of Patients With Severe COVID-19 and Choose the Appropriate Medication Regimens to Deal With Them

Authors: Rasha Ahmadi

Abstract:

In December 2019, a coronavirus, currently identified as SARS-CoV-2, produced a series of acute atypical respiratory illnesses in Wuhan, Hubei Province, China. The sickness induced by this virus was named COVID-19. The virus is transmittable between humans and has caused pandemics worldwide. The number of death tolls continues to climb and a huge number of countries have been obliged to perform social isolation and lockdown. Lack of focused therapy continues to be a problem. Epidemiological research showed that senior patients were more susceptible to severe diseases, whereas children tend to have milder symptoms. In this study, we focus on other possible side effects of COVID-19 and more detailed treatment strategies. Using bioinformatics analysis, we first isolated the gene expression profile of patients with severe COVID-19 from the GEO database. Patients' blood samples were used in the GSE183071 dataset. We then categorized the genes with high and low expression. In the next step, we uploaded the genes separately to the Enrichr database and evaluated our data for signs and symptoms as well as related medication regimens. The results showed that 138 genes with high expression and 108 genes with low expression were observed differentially in the severe COVID-19 VS control group. Symptoms and diseases such as embolism and thrombosis of the abdominal aorta, ankylosing spondylitis, suicidal ideation or attempt, regional enteritis were observed in genes with high expression and in genes with low expression of acute and subacute forms of ischemic heart, CNS infection and poliomyelitis, synovitis and tenosynovitis. Following the detection of diseases and possible signs and symptoms, Carmustine, Bithionol, Leflunomide were evaluated more significantly for high-expression genes and Chlorambucil, Ifosfamide, Hydroxyurea, Bisphenol for low-expression genes. In general, examining the different and invisible aspects of COVID-19 and identifying possible treatments can help us significantly in the emergency and hospitalization of patients.

Keywords: phenotypes, drug regimens, gene expression profiles, bioinformatics analysis, severe COVID-19

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4502 Transcriptome Analysis Reveals Role of Long Non-Coding RNA NEAT1 in Dengue Patients

Authors: Abhaydeep Pandey, Shweta Shukla, Saptamita Goswami, Bhaswati Bandyopadhyay, Vishnampettai Ramachandran, Sudhanshu Vrati, Arup Banerjee

Abstract:

Background: Long non-coding RNAs (lncRNAs) are the important regulators of gene expression and play important role in viral replication and disease progression. The role of lncRNA genes in the pathogenesis of Dengue virus-mediated pathogenesis is currently unknown. Methods: To gain additional insights, we utilized an unbiased RNA sequencing followed by in silico analysis approach to identify the differentially expressed lncRNA and genes that are associated with dengue disease progression. Further, we focused our study on lncRNAs NEAT1 (Nuclear Paraspeckle Assembly Transcript 1) as it was found to be differentially expressed in PBMC of dengue infected patients. Results: The expression of lncRNAs NEAT1, as compared to dengue infection (DI), was significantly down-regulated as the patients developed the complication. Moreover, pairwise analysis on follow up patients confirmed that suppression of NEAT1 expression was associated with rapid fall in platelet count in dengue infected patients. Severe dengue patients (DS) (n=18; platelet count < 20K) when recovered from infection showing high NEAT1 expression as it observed in healthy donors. By co-expression network analysis and subsequent validation, we revealed that coding gene; IFI27 expression was significantly up-regulated in severe dengue cases and negatively correlated with NEAT1 expression. To discriminate DI from dengue severe, receiver operating characteristic (ROC) curve was calculated. It revealed sensitivity and specificity of 100% (95%CI: 85.69 – 97.22) and area under the curve (AUC) = 0.97 for NEAT1. Conclusions: Altogether, our first observations demonstrate that monitoring NEAT1and IFI27 expression in dengue patients could be useful in understanding dengue virus-induced disease progression and may be involved in pathophysiological processes.

Keywords: dengue, lncRNA, NEAT1, transcriptome

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4501 The Effect of Cigarette Smoking on the Production of 20-Hydroxyeicosatetraenoic Acid in Human Platelet

Authors: Yazun Jarrar

Abstract:

Smoking has effect on platelet aggregation and the activity of anti-platelet drugs. The chemical 20-hydroxyeicosatetraenoic acid (20-HETE) is a cardiotoxic arachidonic acid metabolite which increases platelet aggregation. In this study, we investigated the influence of cigarette smoking on 20-HETE levels and protein expression of 20-HETE producing enzyme CYP4A11 in isolated platelets from smoker and non-smoker volunteers. The protein expression and 20-HETE levels were analyzed using immunoblot and High-Performance Liquid Chromatography with Mass Spectrometry (HPL-MS) assays. The results showed that 20-HETE level was higher significantly among smokers than non-smokers (t-test, p-value<0.05). The protein expression of CYP4A11 was significantly higher (t-test, p-value<0.05) among the platelets of smokers. We concluded that cigarette smoking increased the level of platelet activator 20-HETE through increasing the protein expression of CYP4A11. These findings may increase the understanding of smoking-drug interaction during antiplatelets therapy.

Keywords: smoking, 20-HETE, CYP4A11, platelet

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4500 The Expression of Toll-Like Receptors Gene in Peripheral Blood Mononuclear Cells of Betong (KU Line) Chicken

Authors: Chaiwat Boonkaewwan, Anutian Suklek, Jatuporn Rattanasrisomporn, Autchara Kayan

Abstract:

Toll-like receptors (TLR) are conserved microbial sensing receptors located on cell surface that are able to detect different pathogens. The aim of the present study is to examine the expression of TLR gene in peripheral blood mononuclear cell of Betong (KU line) chicken. Blood samples were collected from healthy 12 Betong (KU line) chicken. PBMCs were isolated and maintained in RPMI1640 with 10% FBS, penicillin and streptomycin. Cell viability was determined by trypan blue dye exclusion test. The expression of TLRs gene was investigated by polymerase chain reaction (PCR) technique. Results showed that PBMCs viability from Betong (KU line) chicken was 95.38 ± 1.06%. From the study of TLRs gene expression, results indicated that there are expressions of TLR1.1 TLR1.2 TLR2.1 TLR2.2 TLR3 TLR4 TLR5 TLR 7 TLR15 and TLR21 in PBMCs of Betong (KU line) chicken. In conclusion, PBMCs isolated from blood of Betong (KU line) chicken had a high cell viability ( > 95%). The expression of TLRs in chicken was all found in PBMCs, which indicated that PBMC isolated from the blood of Betong (KU line) chicken can be used as an in vitro immune responses study.

Keywords: toll-like receptor, Betong (KU line) chicken, peripheral blood mononuclear cells

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4499 Role of Endonuclease G in Exogenous DNA Stability in HeLa Cells

Authors: Vanja Misic, Mohamed El-Mogy, Yousef Haj-Ahmad

Abstract:

Endonuclease G (EndoG) is a well conserved mitochondrio-nuclear nuclease with dual lethal and vital roles in the cell. The aim of our study was to examine whether EndoG exerts its nuclease activity on exogenous DNA substrates such as plasmid DNA (pDNA), considering their importance in gene therapy applications. The effects of EndoG knockdown on pDNA stability and levels of encoded reporter gene expression were evaluated in the cervical carcinoma HeLa cells. Transfection of pDNA vectors encoding short-hairpin RNAs (shRNAs) reduced levels of EndoG mRNA and nuclease activity in HeLa cells. In physiological circumstances, EndoG knockdown did not have an effect on the stability of pDNA or the levels of encoded transgene expression as measured over a four day time-course. However, when endogenous expression of EndoG was induced by an extrinsic stimulus, targeting of EndoG by shRNA improved the perceived stability and transgene expression of pDNA vectors. Therefore, EndoG is not a mediator of exogenous DNA clearance, but in non-physiological circumstances it may non-specifically cleave intracellular DNA regardless of its origin. These findings make it unlikely that targeting of EndoG is a viable strategy for improving the duration and level of transgene expression from non-viral DNA vectors in gene therapy efforts.

Keywords: EndoG, silencing, exogenous DNA stability, HeLa cells

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4498 AAV-Mediated Human Α-Synuclein Expression in a Rat Model of Parkinson's Disease –Further Characterization of PD Phenotype, Fine Motor Functional Effects as Well as Neurochemical and Neuropathological Changes over Time

Authors: R. Pussinen, V. Jankovic, U. Herzberg, M. Cerrada-Gimenez, T. Huhtala, A. Nurmi, T. Ahtoniemi

Abstract:

Targeted over-expression of human α-synuclein using viral-vector mediated gene delivery into the substantia nigra of rats and non-human primates has been reported to lead to dopaminergic cell loss and the formation of α-synuclein aggregates reminiscent of Lewy bodies. We have previously shown how AAV-mediated expression of α-synuclein is seen in the chronic phenotype of the rats over 16 week follow-up period. In the context of these findings, we attempted to further characterize this long term PD related functional and motor deficits as well as neurochemical and neuropathological changes in AAV-mediated α-synuclein transfection model in rats during chronic follow-up period. Different titers of recombinant AAV expressing human α-synuclein (A53T) were stereotaxically injected unilaterally into substantia nigra of Wistar rats. Rats were allowed to recover for 3 weeks prior to initial baseline behavioral testing with rotational asymmetry test, stepping test and cylinder test. A similar behavioral test battery was applied again at weeks 5, 9,12 and 15. In addition to traditionally used rat PD model tests, MotoRater test system, a high speed kinematic gait performance monitoring was applied during the follow-up period. Evaluation focused on animal gait between groups. Tremor analysis was performed on weeks 9, 12 and 15. In addition to behavioral end-points, neurochemical evaluation of dopamine and its metabolites were evaluated in striatum. Furthermore, integrity of the dopamine active transport (DAT) system was evaluated by using 123I- β-CIT and SPECT/CT imaging on weeks 3, 8 and 12 after AAV- α-synuclein transfection. Histopathology was examined from end-point samples at 3 or 12 weeks after AAV- α-synuclein transfection to evaluate dopaminergic cell viability and microglial (Iba-1) activation status in substantia nigra by using stereological analysis techniques. This study focused on the characterization and validation of previously published AAV- α-synuclein transfection model in rats but with the addition of novel end-points. We present the long term phenotype of AAV- α-synuclein transfected rats with traditionally used behavioral tests but also by using novel fine motor analysis techniques and tremor analysis which provide new insight to unilateral effects of AAV α-synuclein transfection. We also present data about neurochemical and neuropathological end-points for the dopaminergic system in the model and how well they correlate with behavioral phenotype.

Keywords: adeno-associated virus, alphasynuclein, animal model, Parkinson’s disease

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4497 Analysis of NMDA Receptor 2B Subunit Gene (GRIN2B) mRNA Expression in the Peripheral Blood Mononuclear Cells of Alzheimer's Disease Patients

Authors: Ali̇ Bayram, Semih Dalkilic, Remzi Yigiter

Abstract:

N-methyl-D-aspartate (NMDA) receptor is a subtype of glutamate receptor and plays a pivotal role in learning, memory, neuronal plasticity, neurotoxicity and synaptic mechanisms. Animal experiments were suggested that glutamate-induced excitotoxic injuriy and NMDA receptor blockage lead to amnesia and other neurodegenerative diseases including Alzheimer’s disease (AD), Huntington’s disease, amyotrophic lateral sclerosis. Aim of this study is to investigate association between NMDA receptor coding gene GRIN2B expression level and Alzheimer disease. The study was approved by the local ethics committees, and it was conducted according to the principles of the Declaration of Helsinki and guidelines for the Good Clinical Practice. Peripheral blood was collected 50 patients who diagnosed AD and 49 healthy control individuals. Total RNA was isolated with RNeasy midi kit (Qiagen) according to manufacturer’s instructions. After checked RNA quality and quantity with spectrophotometer, GRIN2B expression levels were detected by quantitative real time PCR (QRT-PCR). Statistical analyses were performed, variance between two groups were compared with Mann Whitney U test in GraphpadInstat algorithm with 95 % confidence interval and p < 0.05. After statistical analyses, we have determined that GRIN2B expression levels were down regulated in AD patients group with respect to control group. But expression level of this gene in each group was showed high variability. İn this study, we have determined that NMDA receptor coding gene GRIN2B expression level was down regulated in AD patients when compared with healthy control individuals. According to our results, we have speculated that GRIN2B expression level was associated with AD. But it is necessary to validate these results with bigger sample size.

Keywords: Alzheimer’s disease, N-methyl-d-aspartate receptor, NR2B, GRIN2B, mRNA expression, RT-PCR

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4496 Variation in Adaptation Strategies of Commelina Communis L. Biotypes under Drought Stress Condition

Authors: Muhammad Haroon, LI Xiangju

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C. communis L. is an important weed of many crop, but very little information about the adaptation strategies of C. communis L. biotypes under drought stress. We investigated five biotypes of C. communis L under drought stress to identify the adaptation mechanism. The expression of drought stress related genes (DRS1, EREB and HRB1) was up-regulated in biotypes, while in some biotypes their expression was down regulated. All five biotypes can thus regulate water balance to consume less water to maintain their status under drought stress condition. This result concluded that C. communis L. biotypes can survive longer under drought stress condition. Weed scientist should seek more effective management strategies to deal with C. communis L.

Keywords: C. communis, biotypes, drought stress, gene expression

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4495 Coronin 1C and miR-128A as Potential Diagnostic Biomarkers for Glioblastoma Multiform

Authors: Denis Mustafov, Emmanouil Karteris, Maria Braoudaki

Abstract:

Glioblastoma multiform (GBM) is a heterogenous primary brain tumour that kills most affected patients. To the authors best knowledge, despite all research efforts there is no early diagnostic biomarker for GBM. MicroRNAs (miRNAs) are short non-coding RNA molecules which are deregulated in many cancers. The aim of this research was to determine miRNAs with a diagnostic impact and to potentially identify promising therapeutic targets for glioblastoma multiform. In silico analysis was performed to identify deregulated miRNAs with diagnostic relevance for glioblastoma. The expression profiles of the chosen miRNAs were then validated in vitro in the human glioblastoma cell lines A172 and U-87MG. Briefly, RNA extraction was carried out using the Trizol method, whilst miRNA extraction was performed using the mirVANA miRNA isolation kit. Quantitative Real-Time Polymerase Chain Reaction was performed to verify their expression. The presence of five target proteins within the A172 cell line was evaluated by Western blotting. The expression of the CORO1C protein within 32 GBM cases was examined via immunohistochemistry. The miRNAs identified in silico included miR-21-5p, miR-34a and miR-128a. These miRNAs were shown to target deregulated GBM genes, such as CDK6, E2F3, BMI1, JAG1, and CORO1C. miR-34a and miR-128a showed low expression profiles in comparison to a control miR-RNU-44 in both GBM cell lines suggesting tumour suppressor properties. Opposing, miR-21-5p demonstrated greater expression indicating that it could potentially function as an oncomiR. Western blotting revealed expression of all five proteins within the A172 cell line. In silico analysis also suggested that CORO1C is a target of miR-128a and miR-34a. Immunohistochemistry demonstrated that 75% of the GBM cases showed moderate to high expression of CORO1C protein. Greater understanding of the deregulated expression of miR-128a and the upregulation of CORO1C in GBM could potentially lead to the identification of a promising diagnostic biomarker signature for glioblastomas.

Keywords: non-coding RNAs, gene expression, brain tumours, immunohistochemistry

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4494 A Computational Study of N–H…O Hydrogen Bonding to Investigate Cooperative Effects

Authors: Setareh Shekarsaraei, Marjan Moridi, Nasser L. Hadipour

Abstract:

In this study, nuclear magnetic resonance spectroscopy and nuclear quadrupole resonance spectroscopy parameters of 14N (Nitrogen in imidazole ring) in N–H…O hydrogen bonding for Histidine hydrochloride monohydrate were calculated via density functional theory. We considered a five-molecule model system of Histidine hydrochloride monohydrate. Also, we examined the trends of environmental effect on hydrogen bonds as well as cooperativity. The functional used in this research is M06-2X which is a good functional and the obtained results have shown good agreement with experimental data. This functional was applied to calculate the NMR and NQR parameters. Some correlations among NBO parameters, NMR, and NQR parameters have been studied which have shown the existence of strong correlations among them. Furthermore, the geometry optimization has been performed using M062X/6-31++G(d,p) method. In addition, in order to study cooperativity and changes in structural parameters, along with increase in cluster size, natural bond orbitals have been employed.

Keywords: hydrogen bonding, density functional theory (DFT), natural bond orbitals (NBO), cooperativity effect

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4493 SCANet: A Workflow for Single-Cell Co-Expression Based Analysis

Authors: Mhaned Oubounyt, Jan Baumbach

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Differences in co-expression networks between two or multiple cells (sub)types across conditions is a pressing problem in single-cell RNA sequencing (scRNA-seq). A key challenge is to define those co-variations that differ between or among cell types and/or conditions and phenotypes to examine small regulatory networks that can explain mechanistic differences. To this end, we developed SCANet, an all-in-one Python package that uses state-of-the-art algorithms to facilitate the workflow of a combined single-cell GCN (Gene Correlation Network) and GRN (Gene Regulatory Networks) pipeline, including inference of gene co-expression modules from scRNA-seq, followed by trait and cell type associations, hub gene detection, co-regulatory networks, and drug-gene interactions. In an example case, we illustrate how SCANet can be applied to identify regulatory drivers behind a cytokine storm associated with mortality in patients with acute respiratory illness. SCANet is available as a free, open-source, and user-friendly Python package that can be easily integrated into systems biology pipelines.

Keywords: single-cell, co-expression networks, drug-gene interactions, co-regulatory networks

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4492 An Optimal Control Model to Determine Body Forces of Stokes Flow

Authors: Yuanhao Gao, Pin Lin, Kees Weijer

Abstract:

In this paper, we will determine the external body force distribution with analysis of stokes fluid motion using mathematical modelling and numerical approaching. The body force distribution is regarded as the unknown variable and could be determined by the idea of optimal control theory. The Stokes flow motion and its velocity are generated by given forces in a unit square domain. A regularized objective functional is built to match the numerical result of flow velocity with the generated velocity data. So that the force distribution could be determined by minimizing the value of objective functional, which is also the difference between the numerical and experimental velocity. Then after utilizing the Lagrange multiplier method, some partial differential equations are formulated consisting the optimal control system to solve. Finite element method and conjugate gradient method are used to discretize equations and deduce the iterative expression of target body force to compute the velocity numerically and body force distribution. Programming environment FreeFEM++ supports the implementation of this model.

Keywords: optimal control model, Stokes equation, finite element method, conjugate gradient method

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4491 The Roles, Strategic Coordination, and Alignment of CTOs: A Systematic Literature Review

Authors: Shailendra Natraj, Kristin Paetzold, B. R. Katzy

Abstract:

The significant role of technology in strategic business decisions has created the need for executives who understand technology and recognize profitable applications to products, services and processes. The role of CTO’s is very complex within technology-based firms, which stretches from the technology aspects to the strategic goal and vision of the firm. Often the roles of CTOs scales from as functional leaders, strategic leaders or supera- functional leaders. In most of the companies the roles are unclear and fuzzy. We in our research are trying to explore each of the orientation and link between leadership types (functional, strategic and super functional) of CTOs, responsibilities, credibility and strategic and conceptual responsibilities. Approach: We conducted a comprehensive literature review with the available databank sources. Results: From the conducted literature review we could identify that most of the research work conducted so far were mainly distributed between roles and responsibilities of CTOs. The available sources pointed were limited to roles of CTOs as functional leaders. Contribution: In our findings based on the literature review, we could identify that apart from the conducted research what so far has not been focused yet are (a) The leadership types (mainly) strategic and super-functional leaders) of CTOs, (b) the responsibilities and credibility of CTOs and (c) the strategic and conceptual responsibilities of CTOs.

Keywords: CTO, chief technology officer, strategy, technology leaders

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4490 The Stem Cell Transcription Co-factor Znf521 Sustains Mll-af9 Fusion Protein In Acute Myeloid Leukemias By Altering The Gene Expression Landscape

Authors: Emanuela Chiarella, Annamaria Aloisio, Nisticò Clelia, Maria Mesuraca

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ZNF521 is a stem cell-associated transcription co-factor, that plays a crucial role in the homeostatic regulation of the stem cell compartment in the hematopoietic, osteo-adipogenic, and neural system. In normal hematopoiesis, primary human CD34+ hematopoietic stem cells display typically a high expression of ZNF521, while its mRNA levels rapidly decrease when these progenitors progress towards erythroid, granulocytic, or B-lymphoid differentiation. However, most acute myeloid leukemias (AMLs) and leukemia-initiating cells keep high ZNF521 expression. In particular, AMLs are often characterized by chromosomal translocations involving the Mixed Lineage Leukemia (MLL) gene, which MLL gene includes a variety of fusion oncogenes arisen from genes normally required during hematopoietic development; once they are fused, they promote epigenetic and transcription factor dysregulation. The chromosomal translocation t(9;11)(p21-22;q23), fusing the MLL gene with AF9 gene, results in a monocytic immune phenotype with an aggressive course, frequent relapses, and a short survival time. To better understand the dysfunctional transcriptional networks related to genetic aberrations, AML gene expression profile datasets were queried for ZNF521 expression and its correlations with specific gene rearrangements and mutations. The results showed that ZNF521 mRNA levels are associated with specific genetic aberrations: the highest expression levels were observed in AMLs involving t(11q23) MLL rearrangements in two distinct datasets (MILE and den Boer); elevated ZNF521 mRNA expression levels were also revealed in AMLs with t(7;12) or with internal rearrangements of chromosome 16. On the contrary, relatively low ZNF521 expression levels seemed to be associated with the t(8;21) translocation, that in turn is correlated with the AML1-ETO fusion gene or the t(15;17) translocation and in AMLs with FLT3-ITD, NPM1, or CEBPα double mutations. Invitro, we found that the enforced co-expression of ZNF521 in cord blood-derived CD34+ cells induced a significant proliferative advantage, improving MLL-AF9 effects on the induction of proliferation and the expansion of leukemic progenitor cells. Transcriptome profiling of CD34+ cells transduced with either MLL-AF9, ZNF521, or a combination of the two transgenes highlighted specific sets of up- or down-regulated genes that are involved in the leukemic phenotype, including those encoding transcription factors, epigenetic modulators, and cell cycle regulators as well as those engaged in the transport or uptake of nutrients. These data enhance the functional cooperation between ZNF521 and MA9, resulting in the development, maintenance, and clonal expansion of leukemic cells. Finally, silencing of ZNF521 in MLL-AF9-transformed primary CD34+ cells inhibited their proliferation and led to their extinction, as well as ZNF521 silencing in the MLL-AF9+ THP-1 cell line resulted in an impairment of their growth and clonogenicity. Taken together, our data highlight ZNF521 role in the control of self-renewal and in the immature compartment of malignant hematopoiesis, which, by altering the gene expression landscape, contributes to the development and/or maintenance of AML acting in concert with the MLL-AF9 fusion oncogene.

Keywords: AML, human zinc finger protein 521 (hZNF521), mixed lineage leukemia gene (MLL) AF9 (MLLT3 or LTG9), cord blood-derived hematopoietic stem cells (CB-CD34+)

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4489 Profile of Programmed Death Ligand-1 (PD-L1) Expression and PD-L1 Gene Amplification in Indonesian Colorectal Cancer Patients

Authors: Akterono Budiyati, Gita Kusumo, Teguh Putra, Fritzie Rexana, Antonius Kurniawan, Aru Sudoyo, Ahmad Utomo, Andi Utama

Abstract:

The presence of the programmed death ligand-1 (PD-L1) has been used in multiple clinical trials and approved as biomarker for selecting patients more likely to respond to immune checkpoint inhibitors. However, the expression of PD-L1 is regulated in different ways, which leads to a different significance of its presence. Positive PD-L1 within tumors may result from two mechanisms, induced PD-L1 expression by T-cell presence or genetic mechanism that lead to constitutive PD-L1 expression. Amplification of PD-L1 genes was found as one of genetic mechanism which causes an increase in PD-L1 expression. In case of colorectal cancer (CRC), targeting immune checkpoint inhibitor has been recommended for patients with microsatellite instable (MSI). Although the correlation between PD-L1 expression and MSI status has been widely studied, so far the precise mechanism of PD-L1 gene activation in CRC patients, particularly in MSI population have yet to be clarified. In this present study we have profiled 61 archived formalin fixed paraffin embedded CRC specimens of patients from Medistra Hospital, Jakarta admitted in 2010 - 2016. Immunohistochemistry was performed to measure expression of PD-L1 in tumor cells as well as MSI status using antibodies against PD-L1 and MMR (MLH1, MSH2, PMS2 and MSH6), respectively. PD-L1 expression was measured on tumor cells with cut off of 1% whereas loss of nuclear MMR protein expressions in tumor cells but not in normal or stromal cells indicated presence of MSI. Subset of PD-L1 positive patients was then assessed for copy number variations (CNVs) using single Tube TaqMan Copy Number Assays Gene CD247PD-L1. We also observed KRAS mutation to profile possible genetic mechanism leading to the presence or absence of PD-L1 expression. Analysis of 61 CRC patients revealed 15 patients (24%) expressed PD-L1 on their tumor cell membranes. The prevalence of surface membrane PD-L1 was significantly higher in patients with MSI (87%; 7/8) compared to patients with microsatellite stable (MSS) (15%; 8/53) (P=0.001). Although amplification of PD-L1 gene was not found among PD-L1 positive patients, low-level amplification of PD-L1 gene was commonly observed in MSS patients (75%; 6/8) than in MSI patients (43%; 3/7). Additionally, we found 26% of CRC patients harbored KRAS mutations (16/61), so far the distribution of KRAS status did not correlate with PD-L1 expression. Our data suggest genetic mechanism through amplification of PD-L1 seems not to be the mechanism underlying upregulation of PD-L1 expression in CRC patients. However, further studies are warranted to confirm the results.

Keywords: colorectal cancer, gene amplification, microsatellite instable, programmed death ligand-1

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4488 SOCS3 Reverses Multidrug Resistance by Inhibiting MDR1 in Mammary Cell Carcinoma

Authors: S. Pradhan, D. Pradhan, G. Tripathy, T. Dasmohapatra

Abstract:

Suppressors of cytokine signalling (SOCS3), a newly indentified anti-apoptotic molecule is a downstream effecter of the receptor tyrosine kinase-Ras signalling pathway. Current study has uncovered that SOCS3 may have wide and imperative capacities, particularly because of its close correlation with malignant tumors. To investigate the impact of SOCS3 on MDR, we analyzed the expression of P-gp and SOCS3 by immune-histochemistry and found there was positive correlation between them. At that point we effectively interfered with RNA translation by the contamination of siRNA of SOCS3 into MCF7/ADM breast cancer cell lines through a lentivirus, and the expression of the target gene was significantly inhibited. After RNAi the drug resistance was reduced altogether and the expression of MDR1 mRNA and P-gp in MCF7/ADM cell lines demonstrated a significant decrease. Likewise the expression of P53 protein increased in a statistically significant manner (p ≤ 0.01) after RNAi exposure. Moreover, flowcytometry analysis uncovers that cell cycle and anti-apoptotic enhancing capacity of cells changed after RNAi treatment. These outcomes proposed SOCS3 may take part in breast cancer MDR by managing MDR1 and P53 expression, changing cell cycle and enhancing the anti-apoptotic ability.

Keywords: SOCS3gene, breast cancer, multidrug resistance, MDR1 gene, RNA interference

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4487 Correlation of Leptin with Clinico-Pathological Features of Breast Cancer

Authors: Saad Al-Shibli, Nasser Amjad, Muna Al Kubaisi, Norra Harun, Shaikh Mizan

Abstract:

Leptin is a multifunctional hormone produced mainly by adipocyte. Leptin and its receptor have long been found associated with breast cancer. The main aim of this study is to investigate the correlation between Leptin/Leptin receptor and the clinicopathological features of breast cancer. Blood samples for ELISA, tissue samples from tumors and adjacent breast tissue were taken from 51 women with breast cancer with a control group of 40 women with a negative mammogram. Leptin and Leptin receptor in the tissues were estimated by immunohistochemistry (IHC). They were localized at the subcellular level by immunocytochemistry using transmission electron microscopy (TEM). Our results showed significant difference in serum leptin level between control and the patient group, but no difference between pre and post-operative serum leptin levels in the patient group. By IHC, we found that the majority of the breast cancer cells studied, stained positively for leptin and leptin receptors with co-expression of leptin and its receptors. No significant correlation was found between leptin/leptin receptors expression with the race, menopausal status, lymph node metastasis, estrogen receptor expression, progesterone receptor expression, HER2 expression and tumor size. Majority of the patients with distant metastasis were associated with high leptin and leptin receptor expression. TEM views both Leptin and Leptin receptor were found highly concentrated within and around the nucleus of the cancer breast cells, indicating nucleus is their principal seat of actions while the adjacent breast epithelial cells showed that leptin gold particles are scattered all over the cell with much less than that of the cancerous cells. However, presence of high concentration of leptin does not necessarily prove its over-expression, because it could be internalized from outside by leptin receptor in the cells. In contrast, leptin receptor is definitely over-expressed in the ductal breast cancer cells. We conclude that reducing leptin levels, blocking its downstream tissue specific signal transduction, and/or blocking the upstream leptin receptor pathway might help in prevention and therapy of breast cancer.

Keywords: breast cancer, expression, leptin, leptin receptors

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4486 Expression of Somatostatin and Neuropeptide Y in Dorsal Root Ganglia Following Hind Paw Incision in Rats

Authors: Anshu Bahl, Saroj Kaler, Shivani Gupta, S B Ray

Abstract:

Background: Somatostatin is an endogenous regulatory neuropeptide. Somatostatin and its analogues play an important role in neuropathic and inflammatory pain. Neuropeptide Y is extensively distributed in the mammalian nervous system. NPY has an important role in blood pressure, circadian rhythm, obesity, appetite and memory. The purpose was to investigate somatostatin and NPY expression in dorsal root ganglia during pain. The plantar incision model in rats is similar to postoperative pain in humans. Methods: 24 adult male Sprague dawley rats were distributed randomly into two groups – Control (n=6) and incision (n=18) groups. Using Hargreaves apparatus, thermal hyperalgesia behavioural test for nociception was done under basal condition and after surgical incision in right hind paw at different time periods (day 1, 3 and 5). The plantar incision was performed as per standard protocol. Perfusion was done using 4% paraformaldehyde followed by extraction of dorsal root ganglia at L4 level. The tissue was processed for immunohistochemical localisation for somatostatin and neuropeptide Y. Results: Post incisional groups (day 1, 3 and 5) exhibited significant decrease of paw withdrawal latency as compared to control groups. Somatostatin expression was noted under basal conditions. It decreased on day 1, but again gradually increased on day 3 and further on day five post incision. The expression of Neuropeptide Y was noted in the cytoplasm of dorsal root ganglia under basal conditions. Compared to control group, expression of neuropeptide Y decreased on day one after incision, but again gradually increased on day 3. Maximum expression was noted on day five post incision. Conclusion: Decrease in paw withdrawal latency indicated nociception, particularly on day 1. In comparison to control, somatostatin and NPY expression was decreased on day one post incision. This could be correlated with increased axoplasmic flow towards the spinal cord. Somatostatin and NPY expression was maximum on day five post incision. This could be due to decreased migration from the site of synthesis towards the spinal cord.

Keywords: dorsal root ganglia, neuropeptide y, postoperative pain, somatostatin

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4485 Relative Expression and Detection of MUB Adhesion Domains and Plantaricin-Like Bacteriocin among Probiotic Lactobacillus plantarum-Group Strains Isolated from Fermented Foods

Authors: Sundru Manjulata Devi, Prakash M. Halami

Abstract:

The immemorial use of fermented foods from vegetables, dairy and other biological sources are of great demand in India because of their health benefits. However, the diversity of Lactobacillus plantarum group (LPG) of vegetable origin has not been revealed yet, particularly with reference to their probiotic functionalities. In the present study, the different species of probiotic Lactobacillus plantarum group (LPG) i.e., L. plantarum subsp. plantarum MTCC 5422 (from fermented cereals), L. plantarum subsp. argentoratensis FG16 (from fermented bamboo shoot) and L. paraplantarum MTCC 9483 (from fermented gundruk) (as characterized by multiplex recA PCR assay) were considered to investigate their relative expression of MUB domains of mub gene (mucin binding protein) by Real time PCR. Initially, the allelic variation in the mub gene was assessed and found to encode three different variants (Type I, II and III). All the three types had 8, 9 and 10 MUB domains respectively (as analysed by Pfam database) and were found to be responsible for adhesion of bacteria to the host intestinal epithelial cells. These domains either get inserted or deleted during speciation or evolutionary events and lead to divergence. The reverse transcriptase qPCR analysis with mubLPF1+R1 primer pair supported variation in amplicon sizes with 300, 500 and 700 bp among different LPG strains. The relative expression of these MUB domains significantly unregulated in the presence of 1% mucin in overnight grown cultures. Simultaneously, the mub gene expressed efficiently by 7 fold in the culture L. paraplantarum MTCC 9483 with 10 MUB domains. An increase in the expression levels for L. plantarum subsp. plantarum MTCC 5422 and L. plantarum subsp. argentoratensis FG16 (MCC 2974) with 9 and 8 repetitive domains was around 4 and 2 fold, respectively. The detection and expression of an integrase (int) gene in the upstream region of mub gene reveals the excision and integration of these repetitive domains. Concurrently, an in vitro adhesion assay to mucin and exclusion of pathogens (such as Listeria monocytogenes and Micrococcus leuteus) was investigated and observed that the L. paraplantarum MTCC 9483 with more adhesion domains has more ability to adhere to mucin and inhibited the growth of pathogens. The production and expression of plantaricin-like bacteriocin (plnNC8 type) in MTCC 9483 suggests the pathogen inhibition. Hence, the expression of MUB domains can act as potential biomarkers in the screening of a novel probiotic LPG strain with adherence property. The present study provides a platform for an easy, rapid, less time consuming, low-cost methodology for the detection of potential probiotic bacteria. It was known that the traditional practices followed in the preparation of fermented bamboo shoots/gundruk/cereals of Indian foods contain different kinds of neutraceuticals for functional food and novel compounds with health promoting factors. In future, a detailed study of these food products can add more nutritive value, consumption and suitable for commercialization.

Keywords: adhesion gene, fermented foods, MUB domains, probiotics

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4484 The Extent to Which Social Factors Affect Urban Functional Mutations and Transformations

Authors: Skirmante Mozuriunaite

Abstract:

Contemporary metropolitan areas and large cities are dynamic, rapidly growing and continuously changing. Thus, urban transformations and mutations are not a new phenomenon, but rather a continuous process. Basic factors of urban transformation are related to development of technologies, globalisation, lifestyle, etc., which, in combination with local factors, have generated an extremely great variety of urban development conditions. This article discusses the main urbanisation processes in Lithuania during last 50 year period and social factors affecting urban functional mutations.

Keywords: dispersion, functional mutations, urbanization, urban mutations, social factors

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4483 Sema4D/Plexin-B1 Signaling Regulates Osteo/Odontogenic Differentiation of Dental Pulp Stem Cells

Authors: Ting Zou, Chengfei Zhang

Abstract:

Objectives: The purpose of this study was to investigate the role of Semaphorin 4D (Sema4D)/Plexin-B1 signaling on osteo/odontogenic differentiation of human dental pulp stem cells (DPSCs) and uncover its molecular mechanism. Methods: DPSCs were cultured in osteo/odontogenic medium. After treatment with Sema4D (10μg/mL), osteo/odontogenic differentiation and mineralization was evaluated by measuring alkaline phosphatase (ALP) activity and alizarin red S staining respectively. The expression of osteo/odontogenic genes (ALP, Col1A1, BSP, and Runx2) was determined by real-time polymerase chain reaction. p-Plexin-B1, Plexin-B1, Col1A1, RhoA, and ErbB2 were analyzed by western. Results: ALP activity and mineralization formation of DPSCs were significantly decreased after treatment with Sema4D (P<0.05). Sema4D significantly down-regulated osteo/odontogenic-related genes expression (ALP, Col1A1, BSP, and Runx2). p-Plexin-B1, Plexin-B1 and RhoA protein expression levels increased after stimulated with Sema4D, while the expression of Col1A1 decreased. Pretreatment with Plexin-B1 antibody blocked Sema4D induced p-Plexin-B1 expression. Conclusion: Sema4D suppressed osteo/odontogenic differentiation of DPSCs via RhoA-mediated pathways.

Keywords: Sema4D/Plexin-B1, dental pulp stem cells, osteo/odontogenic differentiation, alkaline phosphatase (ALP)

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4482 Let-7 Mirnas Regulate Inflammatory Cytokine Production in Bovine Endometrial Cells after Lipopolysaccharide Challenge by Targeting TNFα

Authors: S. Ibrahim, D. Salilew-Wondim, M. Hoelker, C. Looft, E. Tholen, C. Grosse-Brinkhaus, K. Schellander, C. Neuhoff, D. Tesfaye

Abstract:

Bovine endometrial cells appear to have a key role in innate immune defense of the female genital tract. A better understanding of molecular changes in microRNAs (miRNAs) and their target genes expression may identify reliable prognostic indicators for cows that will resolve inflammation and resume cyclicity. In the current study, we hypothesized that let-7 miRNAs family has a primary role in the innate immune defence of the endometrium tissue against bacterial infection, which is partly achieved via regulating mRNA stability of pro-inflammatory cytokines at the post-transcriptional level. Therefore, we conducted two experiments. In the first experiment, primary bovine endometrial cells were challenged with clinical (3.0 μg/ml) and sub-clinical (0.5 μg/ml) doses of lipopolysaccharide (LPS) for 24h. In the 2nd experiment, we have investigated the potential role of let-7 miRNAs (let-7a and let-7f) using gain and loss of function approaches. Additionally, tumor necrosis factor alpha (TNFα), transforming growth factor beta 1 induced transcript 1 (TGFB1I1) and serum deprivation response (SDPR) genes were validated using reporter assay. Here we addressed for the first time that let-7 miRNAs have a precise role in bovine endometrium, where LPS dysregulated let-7 miRNAs family expression was associated with an increased pro-inflammatory cytokine level by directly/indirectly targeting the TNFα, interleukin 6 (IL6), nuclear factor kappa-light-chain enhancer of activated B cells (NFκB), TGFβ1I1 and SDPR genes. To our knowledge, this is the first study showing that TNFα, TGFβ1I1 and SDPR were identified and validated as novel let-7 miRNAs targets and could have a distinct role in inflammatory immune response of LPS challenged bovine endometrial cells. Our data represent a new finding by which uterine homeostasis is maintained through functional regulation of let-7a by down-regulation of pro-inflammatory cytokines expression (TNFα and IL6) at the mRNA and protein levels. These findings suggest that LPS serves as a negative regulator of let-7 miRNAs expression and provides a mechanism for the persistent pro-inflammatory phenotype, which is a hallmark of bovine subclinical endometritis.

Keywords: bovine endometrial cells, let-7, lipopolysaccharide, pro-inflammatory cytokines

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4481 Characterization of Transmembrane Proteins with Five Alpha-Helical Regions

Authors: Misty Attwood, Helgi Schioth

Abstract:

Transmembrane proteins are important components in many essential cell processes such as signal transduction, cell-cell signalling, transport of solutes, structural adhesion activities, and protein trafficking. Due to their involvement in diverse critical activities, transmembrane proteins are implicated in different disease pathways and hence are the focus of intense interest in understanding functional activities, their pathogenesis in disease, and their potential as pharmaceutical targets. Further, as the structure and function of proteins are correlated, investigating a group of proteins with the same tertiary structure, i.e., the same number of transmembrane regions, may give understanding about their functional roles and potential as therapeutic targets. In this in silico bioinformatics analysis, we identify and comprehensively characterize the previously unstudied group of proteins with five transmembrane-spanning regions (5TM). We classify nearly 60 5TM proteins in which 31 are members of ten families that contain two or more family members and all members are predicted to contain the 5TM architecture. Furthermore, nine singlet proteins that contain the 5TM architecture without paralogues detected in humans were also identifying, indicating the evolution of single unique proteins with the 5TM structure. Interestingly, more than half of these proteins function in localization activities through movement or tethering of cell components and more than one-third are involved in transport activities, particularly in the mitochondria. Surprisingly, no receptor activity was identified within this family in sharp contrast with other TM families. Three major 5TM families were identified and include the Tweety family, which are pore-forming subunits of the swelling-dependent volume regulated anion channel in astrocytes; the sidoreflexin family that acts as mitochondrial amino acid transporters; and the Yip1 domain family engaged in vesicle budding and intra-Golgi transport. About 30% of the proteins have enhanced expression in the brain, liver, or testis. Importantly, 60% of these proteins are identified as cancer prognostic markers, where they are associated with clinical outcomes of various tumour types, indicating further investigation into the function and expression of these proteins is important. This study provides the first comprehensive analysis of proteins with 5TM regions and provides details of the unique characteristics and application in pharmaceutical development.

Keywords: 5TM, cancer prognostic marker, drug targets, transmembrane protein

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4480 Functional Characterization of Transcriptional Regulator WhiB Proteins of Mycobacterium Tuberculosis

Authors: Sonam Kumari

Abstract:

Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis, possesses a remarkable feature of entering into and emerging from a persistent state. The mechanism by which Mtb switches from the dormant state to the replicative form is still poorly characterized. Proteome studies have given us an insight into the role of certain proteins in giving stupendous virulence to Mtb, but numerous dotsremain unconnected and unaccounted. The WhiB family of proteins is one such protein that is associated with developmental processes in actinomycetes.Mtb has seven such proteins (WhiB1 to WhiB7).WhiB proteins are transcriptional regulators; their conserved C-terminal HTH motif is involved in DNA binding. They regulate various essential genes of Mtbby binding to their promoter DNA. Biophysical Analysis of the effect of DNA binding on WhiB proteins has not yet been appropriately characterized. Interaction with DNA induces conformational changes in the WhiB proteins, confirmed by steady-state fluorescence and circular dichroism spectroscopy. ITC has deduced thermodynamic parameters and the binding affinity of the interaction. Since these transcription factors are highly unstable in vitro, their stability and solubility were enhanced by the co-expression of molecular chaperones. The present study findings help determine the conditions under which the WhiB proteins interact with their interacting partner and the factors that influence their binding affinity. This is crucial in understanding their role in regulating gene expression in Mtbandin targeting WhiB proteins as a drug target to cure TB.

Keywords: tuberculosis, WhiB proteins, mycobacterium tuberculosis, nucleic acid binding

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4479 Gender Effects in EEG-Based Functional Brain Networks

Authors: Mahdi Jalili

Abstract:

Functional connectivity in the human brain can be represented as a network using electroencephalography (EEG) signals. Network representation of EEG time series can be an efficient vehicle to understand the underlying mechanisms of brain function. Brain functional networks – whose nodes are brain regions and edges correspond to functional links between them – are characterized by neurobiologically meaningful graph theory metrics. This study investigates the degree to which graph theory metrics are sex dependent. To this end, EEGs from 24 healthy female subjects and 21 healthy male subjects were recorded in eyes-closed resting state conditions. The connectivity matrices were extracted using correlation analysis and were further binarized to obtain binary functional networks. Global and local efficiency measures – as graph theory metrics– were computed for the extracted networks. We found that male brains have a significantly greater global efficiency (i.e., global communicability of the network) across all frequency bands for a wide range of cost values in both hemispheres. Furthermore, for a range of cost values, female brains showed significantly greater right-hemispheric local efficiency (i.e., local connectivity) than male brains.

Keywords: EEG, brain, functional networks, network science, graph theory

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4478 Identification of Tissue-Specific Transcription Factors in C. roseus with Emphasis to the TIA Biosynthetic Pathway

Authors: F. M. El-Domyati, A. Atef, S. Edris, N. O. Gadalla, M. A. Al-Kordy, A. M. Ramadan, Y. M. Saad, H. S. Al-Zahrani, A. Bahieldin

Abstract:

Transcriptome retrieved from SRA database of different tissues and treatments of C. roseus was assembled in order to detect tissue-specific transcription factors (TFs) and TFs possibly related to terpenoid indole alkaloids (TIA) pathway. A number of 290 TF-like transcripts along with 12 transcripts related to TIA biosynthetic pathway were divided in terms of co-expression in the different tissues, treatments and genotypes. Three transcripts encoding peroxidases 1 and 12 were downregulated in hairy root, while upregulated in mature leaf. Eight different transcripts of the TIA pathway co-expressed with TFs either functioning downstream tryptophan biosynthesis, e.g., tdc, str1 and sgd, or upstream vindoline biosynthesis, e.g., t16h, omt, nmt, d4h and dat. The results showed no differential expression of TF transcripts in hairy roots knocked down for tdc gene (TDCi) as compared to their wild type controls. There were several evidences of tissue-specific expression of TF transcripts in flower, mature leaf, root/hairy root, stem, seedling, hairy root and immature/mature leaves. Regulation included transcription factor families, e.g., bHLH, MYB and WRKY mostly induced by ABA and/or JA (or MeJA) and regulated during abiotic or biotic stress. The information of tissue-specific regulation and co-expression of TFs and genes in the TIA pathway can be utilized in manipulating alkaloid biosynthesis in C. roseus.

Keywords: SRA database, bHLH, MYB, WRKY, co-expression

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