Colleen L O'Reilly, Selina Uranga, James D Fluckey
{"title":"Culprits or consequences: Understanding the metabolic dysregulation of muscle in diabetes.","authors":"Colleen L O'Reilly, Selina Uranga, James D Fluckey","doi":"10.4331/wjbc.v12.i5.70","DOIUrl":"10.4331/wjbc.v12.i5.70","url":null,"abstract":"<p><p>The prevalence of type 2 diabetes (T2D) continues to rise despite the amount of research dedicated to finding the culprits of this debilitating disease. Skeletal muscle is arguably the most important contributor to glucose disposal making it a clear target in insulin resistance and T2D research. Within skeletal muscle there is a clear link to metabolic dysregulation during the progression of T2D but the determination of culprits <i>vs</i> consequences of the disease has been elusive. Emerging evidence in skeletal muscle implicates influential cross talk between a key anabolic regulatory protein, the mammalian target of rapamycin (mTOR) and its associated complexes (mTORC1 and mTORC2), and the well-described canonical signaling for insulin-stimulated glucose uptake. This new understanding of cellular signaling crosstalk has blurred the lines of what is a culprit and what is a consequence with regard to insulin resistance. Here, we briefly review the most recent understanding of insulin signaling in skeletal muscle, and how anabolic responses favoring anabolism directly impact cellular glucose disposal. This review highlights key cross-over interactions between protein and glucose regulatory pathways and the implications this may have for the design of new therapeutic targets for the control of glucoregulatory function in skeletal muscle.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"12 5","pages":"70-86"},"PeriodicalIF":0.0,"publicationDate":"2021-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/59/61/WJBC-12-70.PMC8473417.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39527983","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stem cells and the pursuit of youth, a tale of limitless possibilities and commercial fraud.","authors":"Batla S Al-Sowayan, Alaa T Al-Shareeda","doi":"10.4331/wjbc.v12.i4.52","DOIUrl":"https://doi.org/10.4331/wjbc.v12.i4.52","url":null,"abstract":"<p><p>This article examines the hype generated around the term \"stem cell\", and the capitalization of the stem cell craze by the cosmetic industry. It started by introducing product lines containing active ingredients derived from plant stem cells. Then, evolved to using own cells for skin regeneration and hair loss treatment, and allogenic cells for the manufacturing of stem cell-derived products. This article also discusses the missing links for safe and reliable stem cell applications in cosmetics, and why local regulatory bodies, members of the industry and consumers must all work together to stop the illegitimate use of the \"stem cell\" good name in unsafe or fraudulent commercial practices.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"12 4","pages":"52-56"},"PeriodicalIF":0.0,"publicationDate":"2021-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/48/92/WJBC-12-52.PMC8316836.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39280851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Polyglutamylase activity of tubulin tyrosine ligase-like 4 is negatively regulated by the never in mitosis gene A family kinase never in mitosis gene A -related kinase 5.","authors":"Talita Diniz Melo-Hanchuk, Jörg Kobarg","doi":"10.4331/wjbc.v12.i3.38","DOIUrl":"https://doi.org/10.4331/wjbc.v12.i3.38","url":null,"abstract":"<p><strong>Background: </strong>Tubulins, building blocks of microtubules, are modified substrates of diverse post-translational modifications including phosphorylation, polyglycylation and polyglutamylation. Polyglutamylation of microtubules, catalyzed by enzymes from the tubulin tyrosine ligase-like (TTLL) family, can regulate interactions with molecular motors and other proteins. Due to the diversity and functional importance of microtubule modifications, strict control of the TTLL enzymes has been suggested.</p><p><strong>Aim: </strong>To characterize the interaction between never in mitosis gene A-related kinase 5 (NEK5) and TTLL4 proteins and the effects of TTLL4 phosphorylation.</p><p><strong>Methods: </strong>The interaction between NEK5 and TTLL4 was identified by yeast two-hybrid screening using the C-terminus of NEK5 (a.a. 260-708) as bait and confirmed by immunoprecipitation. The phosphorylation sites of TTLL4 were identified by mass spectrometry and point mutations were introduced.</p><p><strong>Results: </strong>Here, we show that NEK5 interacts with TTLL4 and regulates its polyglutamylation activity. We further show that NEK5 can also interact with TTLL5 and TTLL7. The silencing of NEK5 increases the levels of polyglutamylation of proteins by increasing the activity of TTLL4. The same effects were observed after the expression of the catalytically inactive form of NEK5. This regulation of TTLL4 activity involves its phosphorylation at Y815 and S1136 amino acid residues.</p><p><strong>Conclusion: </strong>Our results demonstrate, for the first time, the regulation of TTLL activity through phosphorylation, pointing to NEK5 as a potential effector kinase. We also suggest a general control of tubulin polyglutamylation through NEK family members in human cells.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"12 3","pages":"38-51"},"PeriodicalIF":0.0,"publicationDate":"2021-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e7/39/WJBC-12-38.PMC8160597.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39057643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Understanding the function of the tumor microenvironment, and compounds from marine organisms for breast cancer therapy.","authors":"Rama Rao Malla, Batoul Farran, Ganji Purnachandra Nagaraju","doi":"10.4331/wjbc.v12.i2.15","DOIUrl":"10.4331/wjbc.v12.i2.15","url":null,"abstract":"<p><p>The pathology and physiology of breast cancer (BC), including metastasis, and drug resistance, is driven by multiple signaling pathways in the tumor microenvironment (TME), which hamper antitumor immunity. Recently, long non-coding RNAs have been reported to mediate pathophysiological develop-ments such as metastasis as well as immune suppression within the TME. Given the complex biology of BC, novel personalized therapeutic strategies that address its diverse pathophysiologies are needed to improve clinical outcomes. In this review, we describe the advances in the biology of breast neoplasia, including cellular and molecular biology, heterogeneity, and TME. We review the role of novel molecules such as long non-coding RNAs in the pathophysiology of BC. Finally, we provide an up-to-date overview of anticancer compounds extracted from marine microorganisms, crustaceans, and fishes and their synergistic effects in combination with other anticancer drugs. Marine compounds are a new discipline of research in BC and offer a wide range of anti-cancer effects that could be harnessed to target the various pathways involved in BC development, thus assisting current therapeutic regimens.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"12 2","pages":"15-37"},"PeriodicalIF":0.0,"publicationDate":"2021-03-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/e0/7a/WJBC-12-15.PMC8006057.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25558006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Darcy R Denner, Maria Ld Udan-Johns, Michael R Nichols
{"title":"Inhibition of matrix metalloproteinase-9 secretion by dimethyl sulfoxide and cyclic adenosine monophosphate in human monocytes.","authors":"Darcy R Denner, Maria Ld Udan-Johns, Michael R Nichols","doi":"10.4331/wjbc.v12.i1.1","DOIUrl":"https://doi.org/10.4331/wjbc.v12.i1.1","url":null,"abstract":"<p><strong>Background: </strong>Matrix metalloproteinases (MMPs), including MMP-9, are an integral part of the immune response and are upregulated in response to a variety of stimuli. New details continue to emerge concerning the mechanistic and regulatory pathways that mediate MMP-9 secretion. There is significant evidence for regulation of inflammation by dimethyl sulfoxide (DMSO) and 3',5'-cyclic adenosine monophosphate (cAMP), thus investigation of how these two molecules may regulate both MMP-9 and tumor necrosis factor α (TNFα) secretion by human monocytes was of high interest. The hypothesis tested in this study was that DMSO and cAMP regulate MMP-9 and TNFα secretion by distinct mechanisms.</p><p><strong>Aim: </strong>To investigate the regulation of lipopolysaccharide (LPS)-stimulated MMP-9 and tumor necrosis factor α secretion in THP-1 human monocytes by dimethyl sulfoxide and cAMP.</p><p><strong>Methods: </strong>The paper describes a basic research study using THP-1 human monocyte cells. All experiments were conducted at the University of Missouri-St. Louis in the Department of Chemistry and Biochemistry. Human monocyte cells were grown, cultured, and prepared for experiments in the University of Missouri-St. Louis Cell Culture Facility as per accepted guidelines. Cells were treated with LPS for selected exposure times and the conditioned medium was collected for analysis of MMP-9 and TNFα production. Inhibitors including DMSO, cAMP regulators, and anti-TNFα antibody were added to the cells prior to LPS treatment. MMP-9 secretion was analyzed by gel electrophoresis/western blot and quantitated by ImageJ software. TNFα secretion was analyzed by enzyme-linked immuno sorbent assay. All data is presented as the average and standard error for at least 3 trials. Statistical analysis was done using a two-tailed paired Student <i>t</i>-test. <i>P</i> values less than 0.05 were considered significant and designated as such in the Figures. LPS and cAMP regulators were from Sigma-Aldrich, MMP-9 standard and antibody and TNFα antibodies were from R&D Systems, and amyloid-β peptide was from rPeptide.</p><p><strong>Results: </strong>In our investigation of MMP-9 secretion from THP-1 human monocytes, we made the following findings. Inclusion of DMSO in the cell treatment inhibited LPS-induced MMP-9, but not TNFα, secretion. Inclusion of DMSO in the cell treatment at different concentrations inhibited LPS-induced MMP-9 secretion in a dose-dependent fashion. A cell-permeable cAMP analog, dibutyryl cAMP, inhibited both LPS-induced MMP-9 and TNFα secretion. Pretreatment of the cells with the adenylyl cyclase activator forskolin inhibited LPS-induced MMP-9 and TNFα secretion. Pretreatment of the cells with the general cAMP phosphodiesterase inhibitor IBMX reduced LPS-induced MMP-9 and TNFα in a dose-dependent fashion. Pre-treatment of monocytes with an anti-TNFα antibody blocked LPS-induced MMP-9 and TNFα secretion. Amyloid-β peptide induced MMP-9 secret","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"12 1","pages":"1-14"},"PeriodicalIF":0.0,"publicationDate":"2021-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/1f/67/WJBC-12-1.PMC7818474.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"25341736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Atefeh Najafi Khah, Mojdeh Hakemi-Vala, Shiva Samavat, Mohammad Javad Nasiri
{"title":"Prevalence, serotyping and drug susceptibility patterns of <i>Escherichia coli</i> isolates from kidney transplanted patients with urinary tract infections.","authors":"Atefeh Najafi Khah, Mojdeh Hakemi-Vala, Shiva Samavat, Mohammad Javad Nasiri","doi":"10.4331/wjbc.v11.i3.112","DOIUrl":"https://doi.org/10.4331/wjbc.v11.i3.112","url":null,"abstract":"<p><strong>Background: </strong>Extended-spectrum β-lactamase (ESBL)-producing <i>Escherichia coli</i> (<i>E. coli</i>) are among the main pathogens in urinary tract infections (UTIs) among kidney transplant patients (KTPs).</p><p><strong>Aim: </strong>To estimate the prevalence of ESBL-producing <i>E. coli</i> in KTPs and to evaluate the most prevalent serotypes and antibacterial susceptibility patterns of isolated bacteria in Tehran, Iran.</p><p><strong>Methods: </strong>A total of 60 clinical isolates of uropathogenic <i>E. coli</i> were collected from 3 kidney transplant centers from April to May 2019. Antimicrobial susceptibility testing was performed by the disk diffusion method as recommended by the Clinical Laboratory and Standards Institute. The serotyping of <i>E. coli</i> isolates was performed by the slide agglutination method. The presence of <i>bla</i> <sub>TEM</sub>, <i>bla</i> <sub>SHV,</sub> and <i>bla</i> <sub>CTX-M</sub> genes was evaluated by polymerase chain reaction.</p><p><strong>Results: </strong>The frequency of ESBL-producing <i>E. coli</i> in KTPs was found to be 33.4%. All of the 60 <i>E. coli</i> isolates were found to be susceptible to doripenem (100%) and ertapenem (100%). High resistance rates to ampicillin (86%), cefotaxime (80%), and cefazolin (77%) were also documented. The most frequent serotypes were serotype I (50%), serotype II (15%), serotype III (25%), and serotype VI (10%). The gene most frequently found was <i>bla</i> <sub>TEM</sub> (55%), followed by <i>bla</i> <sub>CTX-M</sub> (51%) and <i>bla</i> <sub>SHV</sub> (41%).</p><p><strong>Conclusion: </strong>Molecular analysis showed that <i>bla</i> <sub>TEM</sub> was the most common ESBL-encoding gene. The high resistance to β-lactams antibiotics (<i>i.e.</i>, ampicillin, cefotaxime, and cefazolin) found in <i>E. coli</i> from KTPs with UTIs remains a serious clinical challenge. Further efforts to control ESBL-producing <i>E. coli</i> should include the careful use of all antibiotics as well as barrier precautions to reduce spread.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"11 3","pages":"112-118"},"PeriodicalIF":0.0,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/26/ea/WJBC-11-112.PMC7672941.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38333305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Current understanding of glucose transporter 4 expression and functional mechanisms.","authors":"Tiannan Wang, Jing Wang, Xinge Hu, Xian-Ju Huang, Guo-Xun Chen","doi":"10.4331/wjbc.v11.i3.76","DOIUrl":"10.4331/wjbc.v11.i3.76","url":null,"abstract":"<p><p>Glucose is used aerobically and anaerobically to generate energy for cells. Glucose transporters (GLUTs) are transmembrane proteins that transport glucose across the cell membrane. Insulin promotes glucose utilization in part through promoting glucose entry into the skeletal and adipose tissues. This has been thought to be achieved through insulin-induced GLUT4 translocation from intracellular compartments to the cell membrane, which increases the overall rate of glucose flux into a cell. The insulin-induced GLUT4 translocation has been investigated extensively. Recently, significant progress has been made in our understanding of GLUT4 expression and translocation. Here, we summarized the methods and reagents used to determine the expression levels of <i>Slc2a4</i> mRNA and GLUT4 protein, and GLUT4 translocation in the skeletal muscle, adipose tissues, heart and brain. Overall, a variety of methods such real-time polymerase chain reaction, immunohistochemistry, fluorescence microscopy, fusion proteins, stable cell line and transgenic animals have been used to answer particular questions related to GLUT4 system and insulin action. It seems that insulin-induced GLUT4 translocation can be observed in the heart and brain in addition to the skeletal muscle and adipocytes. Hormones other than insulin can induce GLUT4 translocation. Clearly, more studies of GLUT4 are warranted in the future to advance of our understanding of glucose homeostasis.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"11 3","pages":"76-98"},"PeriodicalIF":0.0,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/bd/29/WJBC-11-76.PMC7672939.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38333304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shruti V Palakuzhiyil, Rita Christopher, Sadanandavalli Retnaswami Chandra
{"title":"Deciphering the modifiers for phenotypic variability of X-linked adrenoleukodystrophy.","authors":"Shruti V Palakuzhiyil, Rita Christopher, Sadanandavalli Retnaswami Chandra","doi":"10.4331/wjbc.v11.i3.99","DOIUrl":"https://doi.org/10.4331/wjbc.v11.i3.99","url":null,"abstract":"<p><p>X-linked adrenoleukodystrophy (X-ALD), an inborn error of peroxisomal β-oxidation, is caused by defects in the ATP Binding Cassette Subfamily D Member 1 (<i>ABCD1</i>) gene. X-ALD patients may be asymptomatic or present with several clinical phenotypes varying from severe to mild, severe cerebral adrenoleuko-dystrophy to mild adrenomyeloneuropathy (AMN). Although most female heterozygotes present with AMN-like symptoms after 60 years of age, occasional cases of females with the cerebral form have been reported. Phenotypic variability has been described within the same kindreds and even among monozygotic twins. There is no association between the nature of <i>ABCD</i>1 mutation and the clinical phenotypes, and the molecular basis of phenotypic variability in X-ALD is yet to be resolved. Various genetic, epigenetic, and environmental influences are speculated to modify the disease onset and severity. In this review, we summarize the observations made in various studies investigating the potential modifying factors regulating the clinical manifestation of X-ALD, which could help understand the pathogenesis of the disease and develop suitable therapeutic strategies.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"11 3","pages":"99-111"},"PeriodicalIF":0.0,"publicationDate":"2020-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/d6/28/WJBC-11-99.PMC7672940.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38333303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Tsvetelina Veselinova Velikova, Stanislav Vasilev Kotsev, Daniel Stefanov Georgiev, Hristiana Momchilova Batselova
{"title":"Immunological aspects of COVID-19: What do we know?","authors":"Tsvetelina Veselinova Velikova, Stanislav Vasilev Kotsev, Daniel Stefanov Georgiev, Hristiana Momchilova Batselova","doi":"10.4331/wjbc.v11.i2.14","DOIUrl":"10.4331/wjbc.v11.i2.14","url":null,"abstract":"<p><p>The newly emerged coronavirus (severe acute respiratory syndrome coronavirus 2 SARS-CoV-2) and the disease that it causes coronavirus disease 2019 (COVID-19) have changed the world we know. Yet, the origin and evolution of SARS-CoV-2 remain mostly vague. Many virulence factors and immune mechanisms contribute to the deteriorating effects on the organism during SARS-CoV-2 infection. Both humoral and cellular immune responses are involved in the pathophysiology of the disease, where the principal and effective immune response towards viral infection is the cell-mediated immunity. The clinical picture of COVID-19, which includes immune memory and reinfection, remains unclear and unpredictable. However, many hopes are put in developing an effective vaccine against the virus, and different therapeutic options have been implemented to find effective, even though not specific, treatment to the disease. We can assume that the interaction between the SARS-CoV-2 virus and the individual's immune system determines the onset and development of the disease significantly.</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"11 2","pages":"14-29"},"PeriodicalIF":0.0,"publicationDate":"2020-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/73/00/WJBC-11-14.PMC7520644.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38460808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Regulation of cytochrome c oxidase contributes to health and optimal life.","authors":"Bernhard Kadenbach","doi":"10.4331/wjbc.v11.i2.52","DOIUrl":"https://doi.org/10.4331/wjbc.v11.i2.52","url":null,"abstract":"<p><p>The generation of cellular energy in the form of ATP occurs mainly in mitochondria by oxidative phosphorylation. Cytochrome c oxidase (CytOx), the oxygen accepting and rate-limiting step of the respiratory chain, regulates the supply of variable ATP demands in cells by \"allosteric ATP-inhibition of CytOx.\" This mechanism is based on inhibition of oxygen uptake of CytOx at high ATP/ADP ratios and low ferrocytochrome c concentrations in the mitochondrial matrix <i>via</i> cooperative interaction of the two substrate binding sites in dimeric CytOx. The mechanism keeps mitochondrial membrane potential ΔΨ<sub>m</sub> and reactive oxygen species (ROS) formation at low healthy values. Stress signals increase cytosolic calcium leading to Ca<sup>2+</sup>-dependent dephosphorylation of CytOx subunit I at the cytosolic side accompanied by switching off the allosteric ATP-inhibition and monomerization of CytOx. This is followed by increase of ΔΨ<sub>m</sub> and formation of ROS. A hypothesis is presented suggesting a dynamic change of binding of NDUFA4, originally identified as a subunit of complex I, between monomeric CytOx (active state with high ΔΨ<sub>m</sub>, high ROS and low efficiency) and complex I (resting state with low ΔΨ<sub>m</sub>, low ROS and high efficiency).</p>","PeriodicalId":23691,"journal":{"name":"World journal of biological chemistry","volume":"11 2","pages":"52-61"},"PeriodicalIF":0.0,"publicationDate":"2020-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/4d/bc/WJBC-11-52.PMC7520645.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38460809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}