Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 13

Search results for: Na+/ K+- ATPase

13 Involvement of BCRP/ABCG2 in Protective Mechanisms of Resveratrol against Methotrexate-Induced Renal Damage in Rats

Authors: Mohamed A. Morsy, Azza A. El-Sheikh, Abdulla Y. Al-Taher

Abstract:

Resveratrol (RES) is a well-known polyphenol antioxidant. We have previously shown that testicular protective effect of RES against the anticancer drug methotrexate (MTX)-induced toxicity involves transporter-mediated mechanisms. Here, we investigated the effect of RES on MTX-induced nephrotoxicity. Rats were administered RES (10 mg/kg/day) for 8 days, with or without a single MTX dose (20 mg/kg i.p.) at day 4 of the experiment. MTX induced nephrotoxicity evident by significantly increase in serum blood urea nitrogen and creatinine compared to control, as well as distortion of kidney microscopic structure. MTX also significantly increased renal nitric oxide level, with induction of inducible nitric oxide synthase expression. MTX also significantly up-regulated fas ligand and caspase 3. Administering RES prior to MTX significantly improved kidney function and microscopic picture, as well as significantly decreased nitrosative and apoptotic markers compared to MTX alone. RES, but not MTX, caused significant increase in expression of breast cancer resistance protein (BCRP), an apical efflux renal transporter that participates in urinary elimination of both MTX and RES. Interestingly, concomitant MTX and RES caused further up-regulation of renal Bcrp compared to RES alone. Using Human BCRP ATPase assay, both RES and MTX exhibited dose-dependent increase in ATPase activity, with Km values of 0.52 ± 0.03 and 30.9 ± 4.2 µM, respectively. Furthermore, combined RES and MTX caused ATPase activity which was significantly less than maximum ATPase activity attained by the positive control; sulfasalazine (12.5 µM). In conclusion, RES exerted nephro-protection against MTX-induced toxicity through anti-nitrosative and anti-apoptotic effects, as well as via up-regulation of renal Bcrp.

Keywords: Resveratrol, nephrotoxicity, methotrexate, breast cancer resistance protein

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12 Supplementation of Corosolic Acid Prevents the Development of Neuropathic Pain in Streptozotocin Induced Diabetic Rats

Authors: Aman Upaganlawar, Chandrasekhar Upasani

Abstract:

The present study was designed to screen the neuroprotective and antioxidant activity of corosolic acid in painful diabetic neuropathy (DN). Diabetes was induced in rats by single dose of STZ (60mg/kg, i.p). Diabetic rats were tested every week for the development of pain, at 5th week rats showed sensation of pain. At 6th week the rats developed significant neuropathic pain. They were divided into different groups and treated with Corosolic acid (2 and 4 mg/kg, p.o) for further two weeks. Pain was assessed in the diabetic rats by mechano-tactil allodynia, mechanical hyperalgesia and cold allodynia. At the end of treatment period rats were scarified and biochemical changes such as plasma glucose level, endogenous antioxidants (Lipid peroxidation, reduced glutathione, superoxide dismutase and catalase) in sciatic nerve were evaluated. Further Na+/K+ ATPase and nitric oxide content was also evaluated. Treatment with corosolic acid for two weeks restored the altered body weight and elevated blood sugar level. Further corosolic acid showed dose dependent reduction in pain in neuropathic animals. The level of endogenous antioxidants enzymes, Na+/K+ ATPase and nitric oxide were significantly prevented. In conclusion, the result of the present study suggests the antidiabetic, antioxidant and neuroprotectieve property of corosolic acid in diabetic rats with neuropathic pain.

Keywords: Diabetes, Neuropathic Pain, antioxidant, corosolic acid

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11 Mitochondrial DNA Defect and Mitochondrial Dysfunction in Diabetic Nephropathy: The Role of Hyperglycemia-Induced Reactive Oxygen Species

Authors: Ghada Al-Kafaji, Mohamed Sabry

Abstract:

Mitochondria are the site of cellular respiration and produce energy in the form of adenosine triphosphate (ATP) via oxidative phosphorylation. They are the major source of intracellular reactive oxygen species (ROS) and are also direct target to ROS attack. Oxidative stress and ROS-mediated disruptions of mitochondrial function are major components involved in the pathogenicity of diabetic complications. In this work, the changes in mitochondrial DNA (mtDNA) copy number, biogenesis, gene expression of mtDNA-encoded subunits of electron transport chain (ETC) complexes, and mitochondrial function in response to hyperglycemia-induced ROS and the effect of direct inhibition of ROS on mitochondria were investigated in an in vitro model of diabetic nephropathy using human renal mesangial cells. The cells were exposed to normoglycemic and hyperglycemic conditions in the presence and absence of Mn(III)tetrakis(4-benzoic acid) porphyrin chloride (MnTBAP) or catalase for 1, 4 and 7 days. ROS production was assessed by the confocal microscope and flow cytometry. mtDNA copy number and PGC-1a, NRF-1, and TFAM, as well as ND2, CYTB, COI, and ATPase 6 transcripts, were all analyzed by real-time PCR. PGC-1a, NRF-1, and TFAM, as well as ND2, CYTB, COI, and ATPase 6 proteins, were analyzed by Western blotting. Mitochondrial function was determined by assessing mitochondrial membrane potential and adenosine triphosphate (ATP) levels. Hyperglycemia-induced a significant increase in the production of mitochondrial superoxide and hydrogen peroxide at day 1 (P < 0.05), and this increase remained significantly elevated at days 4 and 7 (P < 0.05). The copy number of mtDNA and expression of PGC-1a, NRF-1, and TFAM as well as ND2, CYTB, CO1 and ATPase 6 increased after one day of hyperglycemia (P < 0.05), with a significant reduction in all those parameters at 4 and 7 days (P < 0.05). The mitochondrial membrane potential decreased progressively at 1 to 7 days of hyperglycemia with the parallel progressive reduction in ATP levels over time (P < 0.05). MnTBAP and catalase treatment of cells cultured under hyperglycemic conditions attenuated ROS production reversed renal mitochondrial oxidative stress and improved mtDNA, mitochondrial biogenesis, and function. These results show that hyperglycemia-induced ROS caused an early increase in mtDNA copy number, mitochondrial biogenesis and mtDNA-encoded gene expression of the ETC subunits in human mesangial cells as a compensatory response to the decline in mitochondrial function, which precede the mtDNA defect and mitochondrial dysfunction with a progressive oxidative response. Protection from ROS-mediated damage to renal mitochondria induced by hyperglycemia may be a novel therapeutic approach for the prevention/treatment of DN.

Keywords: Oxidative Stress, Diabetic Nephropathy, Mitochondrial dysfunction, catalase, reactive oxygen species, hyperglycemia, mtDNA, manganese superoxide dismutase

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10 A Potential Bio-Pesticidal Molecule Derived from Indian Traditional Plant

Authors: Bunindro Nameirakpam, Sonia Sougrapakam, Shannon B. Olsson, Rajashekar Yallappa

Abstract:

Natural sources for new pesticidal compounds hold promise in view of their eco-friendly nature, selectivity and mammalian safety. Despite a large number of plants that show insecticidal activity and diversity of natural chemistry with inherent eco-friendly nature, newer classes of insecticides have eluded discovery. Artemisia vulgaris, known as Mugwort, is a universal herb used for folk medicine and religious purposes throughout the ancient world. In India, the essential oils of Artemisia vulgaris are used for its insecticidal, anti parasiticidal and antimicrobial properties. Traditionally, the dried leaves of Artemisia vulgaris are used to repel insects as well as rats in and around the granaries in the North-East India. Artemisia vulgaris collected during November from different ecological sites were studied for the bio-pesticidal utility against the stored grain pests. The insecticidal activities were found in the crude extracts of n-hexane and methanol from the samples collected in Sikkim and Manipur respectively. Using silica gel column chromatography protocol, we have isolated one novel bioactive molecule from the aerial parts of Artemisia vulgaris L based on various physical-chemical and spectroscopic techniques (IR, 1H NMR, 13C NMR and mass). The novel bioactive molecule is highly toxic and very low concentration (4.35 µg/l) is needed to control the stored product insects. In additional experiment results clearly showed the involvement of sodium pumps inhibition in the insecticidal action of purified compound in the Sitophilus oryzae. The knockdown activity of the purified compound is concomitant with the in vivo inhibition of Na+/ K+- ATPase. Further, our study showed insignificant differences in the seed germination of control and the treated grains. The lack of adverse effect of the novel bioactive molecule on the seed germination is highly desirable for seed/grain protectant and showing the potential to be developed as possible natural fumigants for the control of stored grain pests. The novel bioactive molecule is selective insecticide with a high margin of safety to mammals and showed promise as novel biopesticide candidate for grain protection. It is believed that Bio-pesticides can serve as the most important pest management tools as far as global safety is concerned.

Keywords: seed germination, bio-pesticides, Indian traditional plant, Artemisia vulgaris, Na+/ K+- ATPase

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9 The Potential of Ursolic Acid Acetate as an Agent for Malarial Chemotherapy

Authors: Mthokozisi B. C. Simelane

Abstract:

Despite the various efforts by governmental and non-governmental organizations aimed at eradicating the disease, malaria is said to kill a child every 30 seconds. Traditional healers use different concoctions prepared from medicinal plants to treat malaria. In the quest to bio-prospect plant-derived triterpenes for anti-malaria activity, we report here the in vivo antiplasmodial activity of ursolic acid acetate (ursolic acid isolated from dichloromethane extract of Mimusops caffra was chemically modified to its acetate derivative). The transdermal administration of ursolic acid acetate (UAA) dose dependently showed complete inhibition of the parasites’ growth at the highest concentration of 400 mg/kg after 15 days of Plasmodium berghei infection. UAA prevented the in vitro aggregation of MDH but did not prevent the expression of PfHsp 70 in E. coli XL1 blue cells. It, however, enhanced PfHsp70 ATPase activity with the specific activity of 65 units (amount of phosphate released 73.83 nmolPi/min.mg). Ursolic acid acetate prevented the formation of hemozoin (60 ± 0.02% at 6 mg/ml). The results suggest that Ursolic acid acetate possesses potential anti-malaria properties.

Keywords: Malaria, Mimusops caffra, ursolic acid acetate, hemozoin

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8 Human LACE1 Functions Pro-Apoptotic and Interacts with Mitochondrial YME1L Protease

Authors: Lukas Stiburek, Jana Cesnekova, Josef Houstek, Jiri Zeman

Abstract:

Cellular function depends on mitochondrial function and integrity that is therefore maintained by several classes of proteins possessing chaperone and/or proteolytic activities. In this work, we focused on characterization of LACE1 (lactation elevated 1) function in mitochondrial protein homeostasis maintenance. LACE1 is the human homologue of yeast mitochondrial Afg1 ATPase, a member of SEC18-NSF, PAS1, CDC48-VCP, TBP family. Yeast Afg1 was shown to be involved in mitochondrial complex IV biogenesis, and based on its similarity with CDC48 (p97/VCP) it was suggested to facilitate extraction of polytopic membrane proteins. Here we show that LACE1, which is a mitochondrial integral membrane protein, exists as part of three complexes of approx. 140, 400 and 500 kDa and is essential for maintenance of fused mitochondrial reticulum and lamellar cristae morphology. Using affinity purification of LACE1-FLAG expressed in LACE1 knockdown background we show that the protein physically interacts with mitochondrial inner membrane protease YME1L. We further show that human LACE1 exhibits significant pro-apoptotic activity and that the protein is required for normal function of the mitochondrial respiratory chain. Thus, our work establishes LACE1 as a novel factor with the crucial role in mitochondrial homeostasis maintenance.

Keywords: apoptosis, Mitochondria, protease, LACE1

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7 Dynamic Cardiac Mitochondrial Proteome Alterations after Ischemic Preconditioning

Authors: Abdelbary Prince, Said Moussa, Hyungkyu Kim, Eman Gouda, Jin Han

Abstract:

We compared the dynamic alterations of mitochondrial proteome of control, ischemia-reperfusion (IR) and ischemic preconditioned (IPC) rabbit hearts. Using 2-DE, we identified 29 mitochondrial proteins that were differentially expressed in the IR heart compared with the control and IPC hearts. For two of the spots, the expression patterns were confirmed by Western blotting analysis. These proteins included succinate dehydrogenase complex, Acyl-CoA dehydrogenase, carnitine acetyltransferase, dihydrolipoamide dehydrogenase, Atpase, ATP synthase, dihydrolipoamide succinyltransferase, ubiquinol-cytochrome c reductase, translation elongation factor, acyl-CoA dehydrogenase, actin alpha, succinyl-CoA Ligase, dihydrolipoamide S-succinyltransferase, citrate synthase, acetyl-Coenzyme A dehydrogenase, creatine kinase, isocitrate dehydrogenase, pyruvate dehydrogenase, prohibitin, NADH dehydrogenase (ubiquinone) Fe-S protein, enoyl Coenzyme A hydratase, superoxide dismutase [Mn], and 24-kDa subunit of complex I. Interestingly, most of these proteins are associated with the mitochondrial respiratory chain, antioxidant enzyme system, and energy metabolism. The results provide clues as to the cardioprotective mechanism of ischemic preconditioning at the protein level and may serve as potential biomarkers for detection of ischemia-induced cardiac injury.

Keywords: Mitochondria, proteome, ischemic preconditioning, cardioprotection

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6 Reconstruction of a Genome-Scale Metabolic Model to Simulate Uncoupled Growth of Zymomonas mobilis

Authors: Maryam Saeidi, Ehsan Motamedian, Seyed Abbas Shojaosadati

Abstract:

Zymomonas mobilis is known as an example of the uncoupled growth phenomenon. This microorganism also has a unique metabolism that degrades glucose by the Entner–Doudoroff (ED) pathway. In this paper, a genome-scale metabolic model including 434 genes, 757 reactions and 691 metabolites was reconstructed to simulate uncoupled growth and study its effect on flux distribution in the central metabolism. The model properly predicted that ATPase was activated in experimental growth yields of Z. mobilis. Flux distribution obtained from model indicates that the major carbon flux passed through ED pathway that resulted in the production of ethanol. Small amounts of carbon source were entered into pentose phosphate pathway and TCA cycle to produce biomass precursors. Predicted flux distribution was in good agreement with experimental data. The model results also indicated that Z. mobilis metabolism is able to produce biomass with maximum growth yield of 123.7 g (mol glucose)-1 if ATP synthase is coupled with growth and produces 82 mmol ATP gDCW-1h-1. Coupling the growth and energy reduced ethanol secretion and changed the flux distribution to produce biomass precursors.

Keywords: genome-scale metabolic model, Zymomonas mobilis, uncoupled growth, flux distribution, ATP dissipation

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5 Application of ATP7B Gene Mutation Analysis in Prenatal Diagnosis of Wilson’s Disease

Authors: Huong M. T. Nguyen, Hoa A. P. Nguyen, Chi V. Phan, Mai P. T. Nguyen, Ngoc D. Ngo, Van T. Ta, Hai T. Le

Abstract:

Wilson’s disease is an autosomal recessive disorder of copper metabolism, which is caused by mutation in copper- transporting P-type ATPase (ATP7B). The mechanism of this disease is a failure of hepatic excretion of copper to the bile, and it leads to copper deposits in the liver and other organs. Most clinical symptoms of Wilson’s disease can present as liver disease and/or neurologic disease. Objective: The goal of the study is prenatal diagnosis for pregnant women at high risk of Wilson’s disease in Northern Vietnam. Material and method: Three probands with clinically diagnosed liver disease were detected in the mutations of 21 exons and exon-intron boundaries of the ATP7B gene by direct Sanger-sequencing. Prenatal diagnoses were performed by amniotic fluid sampling from pregnant women in the 16th-18th weeks of pregnancy after the genotypes of parents with the probands were identified. Result: A total of three different mutations of the probands, including of S105*, P1052L, P1273G, were detected. Among three fetuses which underwent prenatal genetic testing, one fetus was homozygote; two fetuses were carriers. Conclusion: Genetic testing provided a useful method for prenatal diagnosis, and is a basis for genetic counseling.

Keywords: Prenatal Diagnosis, Genetic Testing, ATP7B gene, pedigree, Wilson disease

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4 Antioxidant Enzymes and Crude Mitochondria ATPases in the Radicle of Germinating Bean (Vigna unguiculata) Exposed to Different Concentrations of Crude Oil

Authors: Stella O. Olubodun, George E. Eriyamremu

Abstract:

The study examined the effect of Bonny Light whole crude oil (WC) and its water soluble fraction (WSF) on the activities of antioxidant enzymes (catalase (CAT) and superoxide dismutase (SOD)) and crude mitochondria ATPases in the radicle of germinating bean (Vigna unguiculata). The percentage germination, level of lipid peroxidation, antioxidant enzyme, and mitochondria Ca2+ and Mg2+ ATPase activities were measured in the radicle of bean after 7, 14, and 21 days post germination. Viable bean seeds were planted in soils contaminated with 10ml, 25ml, and 50ml of whole crude oil (WC) and its water soluble fraction (WSF) to obtain 2, 5, and 10% v/w crude oil contamination. There was dose dependent reduction of the number of bean seeds that germinated in the contaminated soils compared with control (p<0.001). The activities of the antioxidant enzymes, as well as, adenosine triphosphatase enzymes, were also significantly (p<0.001) altered in the radicle of the plants grown in contaminated soil compared with the control. Generally, the level of lipid peroxidation was highest after 21 days post germination when compared with control. Stress to germinating bean caused by Bonny Light crude oil or its water soluble fraction resulted in adaptive changes in crude mitochondria ATPases in the radicle.

Keywords: antioxidant enzymes, radicle, bonny light crude oil, mitochondria ATPases

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3 Mutation Analysis of the ATP7B Gene in 43 Vietnamese Wilson’s Disease Patients

Authors: Huong M. T. Nguyen, Hoa A. P. Nguyen, Mai P. T. Nguyen, Ngoc D. Ngo, Van T. Ta, Hai T. Le, Chi V. Phan

Abstract:

Wilson’s disease (WD) is an autosomal recessive disorder of the copper metabolism, which is caused by a mutation in the copper-transporting P-type ATPase (ATP7B). The mechanism of this disease is the failure of hepatic excretion of copper to bile, and leads to copper deposits in the liver and other organs. The ATP7B gene is located on the long arm of chromosome 13 (13q14.3). This study aimed to investigate the gene mutation in the Vietnamese patients with WD, and make a presymptomatic diagnosis for their familial members. Forty-three WD patients and their 65 siblings were identified as having ATP7B gene mutations. Genomic DNA was extracted from peripheral blood samples; 21 exons and exon-intron boundaries of the ATP7B gene were analyzed by direct sequencing. We recognized four mutations ([R723=; H724Tfs*34], V1042Cfs*79, D1027H, and IVS6+3A>G) in the sum of 20 detectable mutations, accounting for 87.2% of the total. Mutation S105* was determined to have a high rate (32.6%) in this study. The hotspot regions of ATP7B were found at exons 2, 16, and 8, and intron 14, in 39.6 %, 11.6 %, 9.3%, and 7 % of patients, respectively. Among nine homozygote/compound heterozygote siblings of the patients with WD, three individuals were determined as asymptomatic by screening mutations of the probands. They would begin treatment after diagnosis. In conclusion, 20 different mutations were detected in 43 WD patients. Of this number, four novel mutations were explored, including [R723=; H724Tfs*34], V1042Cfs*79, D1027H, and IVS6+3A>G. The mutation S105* is the most prevalent and has been considered as a biomarker that can be used in a rapid detection assay for diagnosis of WD patients. Exons 2, 8, and 16, and intron 14 should be screened initially for WD patients in Vietnam. Based on risk profile for WD, genetic testing for presymptomatic patients is also useful in diagnosis and treatment.

Keywords: ATP7B gene, mutation detection, presymptomatic diagnosis, Vietnamese Wilson’s disease

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2 Hypolipidemic and Antioxidant Effects of Mycelial Polysaccharides from Calocybe indica in Hyperlipidemic Rats Induced by High-Fat Diet

Authors: Govindan Sudha, Mathumitha Subramaniam, Alamelu Govindasamy, Sasikala Gunasekaran

Abstract:

The aim of this study was to investigate the protective effect of Hypsizygus ulmarius polysaccharides (HUP) on reducing oxidative stress, cognitive impairment and neurotoxicity in D-galactose induced aging mice. Mice were subcutaneously injected with D-galactose (150 mg/kg per day) for 6 weeks and were administered HUP simultaneously. Aged mice receiving vitamin E (100 mg/kg) served as positive control. Chronic administration of D-galactose significantly impaired cognitive performance oxidative defence and mitochondrial enzymes activities as compared to control group. The results showed that HUP (200 and 400 mg/kg) treatment significantly improved the learning and memory ability in Morris water maze test. Biochemical examination revealed that HUP significantly increased the decreased activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST), mitochondrial enzymes-NADH dehydrogenase, malate dehydrogenase (MDH), isocitrate dehydrogenase (ICDH), Na+K+, Ca2+, Mg2+ATPase activities, elevated the lowered total anti-oxidation capability (TAOC), glutathione (GSH), vitamin C and decreased the raised acetylcholinesterase (AChE) activities, malondialdehyde (MDA), hydroperoxide (HPO), protein carbonyls (PCO), advanced oxidation protein products (AOPP) levels in brain of aging mice induced by D-gal in a dose-dependent manner. In conclusion, present study highlights the potential role of HUP against D-galactose induced cognitive impairment, biochemical and mitochondrial dysfunction in mice. In vitro studies on the effect of HUP on scavenging DPPH, ABTS, DMPD, OH radicals, reducing power, B-carotene bleaching and lipid peroxidation inhibition confirmed the free radical scavenging and antioxidant activity of HUP. The results suggest that HUP possesses anti-aging efficacy and may have potential in treatment of neurodegenerative diseases.

Keywords: Aging, Antioxidants, mushroom, neurotoxicity

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1 The Molecular Mechanism of Vacuolar Function in Yeast Cell Homeostasis

Authors: Chang-Hui Shen, Paulina Konarzewska

Abstract:

Cell homeostasis is regulated by vacuolar activity and it has been shown that lipid composition of the vacuole plays an important role in vacuolar function. The major phosphoinositide species present in the vacuolar membrane include phosphatidylinositol 3,5-biphosphate (PI(3,5)P₂) which is generated from PI(3)P controlled by Fab1p. Deletion of FAB1 gene reduce the synthesis of PI(3,5)P₂ and thus result in enlarged or fragmented vacuoles, with neutral vacuolar pH due to reduced vacuolar H⁺-ATPase activity. These mutants also exhibited poor growth at high extracellular pH and in the presence of CaCl₂. Conversely, VPS34 regulates the synthesis of PI(3)P from phosphatidylinositol (PI), and the lack of Vps34p results in the reduction of vacuolar activity. Although the cellular observations are clear, it is still unknown about the molecular mechanism between the phospholipid biosynthesis pathway and vacuolar activity. Since both VPS34 and FAB1 are important in vacuolar activity, we hypothesize that the molecular mechanism of vacuolar function might be regulated by the transcriptional regulators of phospholipid biosynthesis. In this study, we study the role of the major phospholipid biosynthesis transcription factor, INO2, in the regulation of vacuolar activity. We first performed qRT-PCR to examine the effect of Ino2p on the expression of VPS34 and FAB1. Our results showed that VPS34 was upregulated in the presence of inositol for both WT and ino2Δ cells. However, FAB1 was only upregulated significantly in ino2Δ cells. This indicated that Ino2p might be the negative regulator for FAB1 expression. Next, growth sensitivity experiment showed that WT, vma3Δ, and ino2Δ grew well in growth medium buffered to pH 5.5 containing 10 mM CaCl₂. As cells were switched to growth medium buffered to pH 7 containing CaCl₂ WT, ino2Δ and opi1Δ showed growth reduction, whereas vma3Δ was completely nonviable. As the concentration of CaCl₂ was increased to 60 mM, ino2Δ cells showed moderate growth reduction compared to WT. This result suggests that ino2Δ cells have better vacuolar activity. Microscopic analysis and vacuolar acidification were employed to further elucidate the importance of INO2 in vacuolar homeostasis. Analysis of vacuolar morphology indicated that WT and vma3Δ cells displayed vacuoles that occupied a small area of the cell when grown in media buffered to pH 5.5. Whereas, ino2Δ displayed fragmented vacuoles. On the other hand, all strains grown in media buffered to pH 7, exhibited enlarged vacuoles that occupied most of the cell’s surface. This indicated that the presence of INO2 may play negative effect in vacuolar morphology when cells are grown in media buffered to pH 5.5. Furthermore, vacuolar acidification assay showed that only vma3Δ cells displayed notably less acidic vacuoles as cells were grown in media buffered to pH 5.5 and pH 7. Whereas, ino2Δ cells displayed more acidic pH compared to WT at pH7. Taken together, our results demonstrated the molecular mechanism of the vacuolar activity regulated by the phospholipid biosynthesis transcription factors Ino2p. Ino2p negatively regulates vacuolar activity through the expression of FAB1.

Keywords: Homeostasis, vacuole, phospholipid, Ino2p, FAB1

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