Paramesha Bugga, Michael W Stoner, Janet R Manning, Bellina A S Mushala, Nisha Bhattarai, Maryam Sharifi-Sanjani, Bradley R Webster, Dharendra Thapa, Iain Scott
GCN5L1, also known as BLOC1S1 and BLOS1, is a small intracellular protein involved in many key biological processes. Over the last decade, GCN5L1 has been implicated in the regulation of protein lysine acetylation, energy metabolism, endo-lysosomal function, and cellular immune pathways. An increasing number of published papers have used commercially-available reagents to interrogate GCN5L1 function. However, in many cases these reagents have not been rigorously validated, leading to potentially misleading results. In this report we tested several commercially-available antibodies for GCN5L1, and found that two-thirds of those available did not unambiguously detect the protein by western blot in cultured mouse cells or ex vivo liver tissue. These data suggest that previously published studies which used these unverified antibodies to measure GCN5L1 protein abundance, in the absence of other independent methods of corroboration, should be interpreted with appropriate caution.
GCN5L1又称BLOC1S1和BLOS1,是一种细胞内小蛋白,参与了许多关键的生物过程。在过去十年中,GCN5L1 与蛋白质赖氨酸乙酰化、能量代谢、内溶酶体功能和细胞免疫途径的调控有关。越来越多已发表的论文使用市售试剂来检测 GCN5L1 的功能。然而,在许多情况下,这些试剂并没有经过严格的验证,可能会导致误导性的结果。在本报告中,我们测试了几种市售的 GCN5L1 抗体,发现三分之二的抗体在培养的小鼠细胞或体内外肝脏组织中不能通过 Western 印迹明确检测到该蛋白。这些数据表明,在没有其他独立方法证实的情况下,以前发表的使用这些未经验证的抗体来测量 GCN5L1 蛋白丰度的研究应该谨慎解读。
{"title":"Validation of GCN5L1/BLOC1S1/BLOS1 antibodies using knockout cells and tissue.","authors":"Paramesha Bugga, Michael W Stoner, Janet R Manning, Bellina A S Mushala, Nisha Bhattarai, Maryam Sharifi-Sanjani, Bradley R Webster, Dharendra Thapa, Iain Scott","doi":"10.1042/BCJ20230302","DOIUrl":"10.1042/BCJ20230302","url":null,"abstract":"<p><p>GCN5L1, also known as BLOC1S1 and BLOS1, is a small intracellular protein involved in many key biological processes. Over the last decade, GCN5L1 has been implicated in the regulation of protein lysine acetylation, energy metabolism, endo-lysosomal function, and cellular immune pathways. An increasing number of published papers have used commercially-available reagents to interrogate GCN5L1 function. However, in many cases these reagents have not been rigorously validated, leading to potentially misleading results. In this report we tested several commercially-available antibodies for GCN5L1, and found that two-thirds of those available did not unambiguously detect the protein by western blot in cultured mouse cells or ex vivo liver tissue. These data suggest that previously published studies which used these unverified antibodies to measure GCN5L1 protein abundance, in the absence of other independent methods of corroboration, should be interpreted with appropriate caution.</p>","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":" ","pages":"643-651"},"PeriodicalIF":4.4,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140853083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
E3 ubiquitin ligase, ring finger protein 138 (RNF138) is involved in several biological processes; however, its role in myeloid differentiation or tumorigenesis remains unclear. RNAseq data from TNMplot showed that RNF138 mRNA levels are highly elevated in acute myeloid leukemia (AML) bone marrow samples as compared with bone marrow of normal volunteers. Here, we show that RNF138 serves as an E3 ligase for the tumor suppressor CCAAT/enhancer binding protein (C/EBPα) and promotes its degradation leading to myeloid differentiation arrest in AML. Wild-type RNF138 physically interacts with C/EBPα and promotes its ubiquitin-dependent proteasome degradation while a mutant RNF-138 deficient in ligase activity though interacts with C/EBPα, fails to down-regulate it. We show that RNF138 depletion enhances endogenous C/EBPα levels in peripheral blood mononuclear cells (PBMCs) isolated from healthy volunteers. Our data further shows that RNF138-mediated degradation of C/EBPα negatively affects its transactivation potential on its target genes. Furthermore, RNF138 overexpression inhibits all-trans-retinoic acid-induced differentiation of HL-60 cells whereas RNF138 RNAi enhances. In line with RNF138 inhibiting C/EBPα protein turnover, we also observed that RNF138 overexpression inhibited β-estradiol (E2)-induced C/EBPα driven granulocytic differentiation in C/EBPα inducible K562-p42C/EBPα-estrogen receptor cells. Furthermore, we also recapitulated these findings in PBMCs isolated from AML patients where depletion of RNF138 increased the expression of myeloid differentiation marker CD11b. These results suggest that RNF138 inhibits myeloid differentiation by targeting C/EBPα for proteasomal degradation and may provide a plausible mechanism for loss of C/EBPα expression often observed in myeloid leukemia. Also, targeting RNF138 may resolve differentiation arrest by restoring C/EBPα expression in AML.
{"title":"Ring finger protein 138 inhibits transcription factor C/EBPα protein turnover leading to differentiation arrest in acute myeloid leukemia.","authors":"Anil Kumar Singh, Vishal Upadhyay, Arppita Sethi, Sangita Chowdhury, Shivkant Mishra, Shailendra Prasad Verma, Madan Lal Brahma Bhatt, Arun Kumar Trivedi","doi":"10.1042/BCJ20240027","DOIUrl":"10.1042/BCJ20240027","url":null,"abstract":"<p><p>E3 ubiquitin ligase, ring finger protein 138 (RNF138) is involved in several biological processes; however, its role in myeloid differentiation or tumorigenesis remains unclear. RNAseq data from TNMplot showed that RNF138 mRNA levels are highly elevated in acute myeloid leukemia (AML) bone marrow samples as compared with bone marrow of normal volunteers. Here, we show that RNF138 serves as an E3 ligase for the tumor suppressor CCAAT/enhancer binding protein (C/EBPα) and promotes its degradation leading to myeloid differentiation arrest in AML. Wild-type RNF138 physically interacts with C/EBPα and promotes its ubiquitin-dependent proteasome degradation while a mutant RNF-138 deficient in ligase activity though interacts with C/EBPα, fails to down-regulate it. We show that RNF138 depletion enhances endogenous C/EBPα levels in peripheral blood mononuclear cells (PBMCs) isolated from healthy volunteers. Our data further shows that RNF138-mediated degradation of C/EBPα negatively affects its transactivation potential on its target genes. Furthermore, RNF138 overexpression inhibits all-trans-retinoic acid-induced differentiation of HL-60 cells whereas RNF138 RNAi enhances. In line with RNF138 inhibiting C/EBPα protein turnover, we also observed that RNF138 overexpression inhibited β-estradiol (E2)-induced C/EBPα driven granulocytic differentiation in C/EBPα inducible K562-p42C/EBPα-estrogen receptor cells. Furthermore, we also recapitulated these findings in PBMCs isolated from AML patients where depletion of RNF138 increased the expression of myeloid differentiation marker CD11b. These results suggest that RNF138 inhibits myeloid differentiation by targeting C/EBPα for proteasomal degradation and may provide a plausible mechanism for loss of C/EBPα expression often observed in myeloid leukemia. Also, targeting RNF138 may resolve differentiation arrest by restoring C/EBPα expression in AML.</p>","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":" ","pages":"653-666"},"PeriodicalIF":4.4,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140861843","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Arline Fernández-Silva Ana L Juárez-Vázquez Lilian González-Segura Javier Andrés Juárez-Díaz Rosario A Muñoz-Clares
{"title":"Correction: The uncharacterized Pseudomonas aeruginosa PA4189 is a novel and efficient aminoacetaldehyde dehydrogenase.","authors":"Arline Fernández-Silva Ana L Juárez-Vázquez Lilian González-Segura Javier Andrés Juárez-Díaz Rosario A Muñoz-Clares","doi":"10.1042/BCJ20220567_COR","DOIUrl":"10.1042/BCJ20220567_COR","url":null,"abstract":"","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"481 10","pages":"667"},"PeriodicalIF":4.4,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140897336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Knowledge of the primary structure of neuronal NO synthase (nNOS) in skeletal muscle is still conflicting and needs further clarification. To elucidate the expression patterns of nNOS isoforms at both mRNA and protein level, systematic reverse transcription (RT)-PCR and epitope mapping by qualitative immunoblot analysis on skeletal muscle of C57/BL6 mice were performed. The ability of the nNOS isoforms to form aggregates was characterized by native low-temperature polyacrylamide electrophoresis (LT-PAGE). The molecular analysis was focused on the rectus femoris (RF) muscle, a skeletal muscle with a nearly balanced ratio of nNOS α- and β-isoforms. RT-PCR amplificates from RF muscles showed exclusive exon-1d mRNA expression, either with or without exon-μ. Epitope mapping demonstrated the simultaneous expression of the nNOS splice variants α/μ, α/non-μ, β/μ and β/non-μ. Furthermore, immunoblotting suggests that the transition between nNOS α- and β-isoforms lies within exon-3. In LT-PAGE, three protein nNOS associated aggregates were detected in homogenates of RF muscle and tibialis anterior muscle: a 320 kDa band containing nNOS α-isoforms, while 250 and 300 kDa bands consist of nNOS β-isoforms that form homodimers or heterodimers with non-nNOS proteins.
{"title":"Expression of neuronal NO synthase α- and β-isoforms in skeletal muscle of mice","authors":"Baum, Oliver","doi":"10.1042/bcj20230458","DOIUrl":"https://doi.org/10.1042/bcj20230458","url":null,"abstract":"Knowledge of the primary structure of neuronal NO synthase (nNOS) in skeletal muscle is still conflicting and needs further clarification. To elucidate the expression patterns of nNOS isoforms at both mRNA and protein level, systematic reverse transcription (RT)-PCR and epitope mapping by qualitative immunoblot analysis on skeletal muscle of C57/BL6 mice were performed. The ability of the nNOS isoforms to form aggregates was characterized by native low-temperature polyacrylamide electrophoresis (LT-PAGE). The molecular analysis was focused on the rectus femoris (RF) muscle, a skeletal muscle with a nearly balanced ratio of nNOS α- and β-isoforms. RT-PCR amplificates from RF muscles showed exclusive exon-1d mRNA expression, either with or without exon-μ. Epitope mapping demonstrated the simultaneous expression of the nNOS splice variants α/μ, α/non-μ, β/μ and β/non-μ. Furthermore, immunoblotting suggests that the transition between nNOS α- and β-isoforms lies within exon-3. In LT-PAGE, three protein nNOS associated aggregates were detected in homogenates of RF muscle and tibialis anterior muscle: a 320 kDa band containing nNOS α-isoforms, while 250 and 300 kDa bands consist of nNOS β-isoforms that form homodimers or heterodimers with non-nNOS proteins.","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"7 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140642296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Duaa W Al-Sadeq, Carolina Conter, Angelos Thanassoulas, Nader Al-Dewik, Bared Safieh-Garabedian, Luis Alfonso Martínez-Cruz, Gheyath K Nasrallah, Alessandra Astegno, Michail Nomikos
Homocystinuria is a rare disease caused by mutations in the CBS gene that results in a deficiency of cystathionine β-synthase (CBS). CBS is an essential pyridoxal 5'-phosphate (PLP)-dependent enzyme in the transsulfuration pathway, responsible for combining serine with homocysteine to produce cystathionine, whose activity is enhanced by the allosteric regulator S-adenosylmethionine (SAM). CBS also plays a role in generating hydrogen sulfide (H2S), a gaseous signaling molecule with diverse regulatory functions within the vascular, nervous, and immune systems. In this study, we present the clinical and biochemical characterization of two novel CBS missense mutations that do not respond to pyridoxine treatment, namely c.689T > A (L230Q) and 215A > T (K72I), identified in a Chinese patient. We observed that the disease-associated K72I genetic variant had no apparent effects on the spectroscopic and catalytic properties of the full-length enzyme. In contrast, the L230Q variant expressed in Escherichia coli did not fully retain heme and when compared with the wild-type enzyme, it exhibited more significant impairments in both the canonical cystathionine-synthesis and the alternative H2S-producing reactions. This reduced activity is consistent with both in vitro and in silico evidence, which indicates that the L230Q mutation significantly decreases the overall protein's stability, which in turn, may represent the underlying cause of its pathogenicity.
{"title":"Biochemical and structural impact of two novel missense mutations in cystathionine β-synthase gene associated with homocystinuria.","authors":"Duaa W Al-Sadeq, Carolina Conter, Angelos Thanassoulas, Nader Al-Dewik, Bared Safieh-Garabedian, Luis Alfonso Martínez-Cruz, Gheyath K Nasrallah, Alessandra Astegno, Michail Nomikos","doi":"10.1042/BCJ20240012","DOIUrl":"10.1042/BCJ20240012","url":null,"abstract":"<p><p>Homocystinuria is a rare disease caused by mutations in the CBS gene that results in a deficiency of cystathionine β-synthase (CBS). CBS is an essential pyridoxal 5'-phosphate (PLP)-dependent enzyme in the transsulfuration pathway, responsible for combining serine with homocysteine to produce cystathionine, whose activity is enhanced by the allosteric regulator S-adenosylmethionine (SAM). CBS also plays a role in generating hydrogen sulfide (H2S), a gaseous signaling molecule with diverse regulatory functions within the vascular, nervous, and immune systems. In this study, we present the clinical and biochemical characterization of two novel CBS missense mutations that do not respond to pyridoxine treatment, namely c.689T > A (L230Q) and 215A > T (K72I), identified in a Chinese patient. We observed that the disease-associated K72I genetic variant had no apparent effects on the spectroscopic and catalytic properties of the full-length enzyme. In contrast, the L230Q variant expressed in Escherichia coli did not fully retain heme and when compared with the wild-type enzyme, it exhibited more significant impairments in both the canonical cystathionine-synthesis and the alternative H2S-producing reactions. This reduced activity is consistent with both in vitro and in silico evidence, which indicates that the L230Q mutation significantly decreases the overall protein's stability, which in turn, may represent the underlying cause of its pathogenicity.</p>","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":" ","pages":"569-585"},"PeriodicalIF":4.1,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140334594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hawley, Simon A., Russell, Fiona M., Hardie, D. Grahame
The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation. Surprisingly, binding of ADP has been reported to mimic the first two effects, but not the third. We now show that at physiologically relevant concentrations of Mg.ATP2− (above those used in the standard assay) ADP binding does cause allosteric activation. However, ADP causes only a modest activation because (unlike AMP), at concentrations just above those where activation becomes evident, ADP starts to cause competitive inhibition at the catalytic site. Our results cast doubt on the physiological relevance of the effects of ADP and suggest that AMP is the primary activator in vivo. We have also made mutations to hydrophobic residues involved in binding adenine nucleotides at each of the three γ subunit CBS repeats of the human α2β2γ1 complex and examined their effects on regulation by AMP and ADP. Mutation of the CBS3 site has the largest effects on all three mechanisms of AMP activation, especially at lower ATP concentrations, while mutation of CBS4 reduces the sensitivity to AMP. All three sites appear to be required for allosteric activation by ADP.
{"title":"AMP-activated protein kinase can be allosterically activated by ADP but AMP remains the key activating ligand","authors":"Hawley, Simon A., Russell, Fiona M., Hardie, D. Grahame","doi":"10.1042/bcj20240082","DOIUrl":"https://doi.org/10.1042/bcj20240082","url":null,"abstract":"The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation. Surprisingly, binding of ADP has been reported to mimic the first two effects, but not the third. We now show that at physiologically relevant concentrations of Mg.ATP2− (above those used in the standard assay) ADP binding does cause allosteric activation. However, ADP causes only a modest activation because (unlike AMP), at concentrations just above those where activation becomes evident, ADP starts to cause competitive inhibition at the catalytic site. Our results cast doubt on the physiological relevance of the effects of ADP and suggest that AMP is the primary activator in vivo. We have also made mutations to hydrophobic residues involved in binding adenine nucleotides at each of the three γ subunit CBS repeats of the human α2β2γ1 complex and examined their effects on regulation by AMP and ADP. Mutation of the CBS3 site has the largest effects on all three mechanisms of AMP activation, especially at lower ATP concentrations, while mutation of CBS4 reduces the sensitivity to AMP. All three sites appear to be required for allosteric activation by ADP.","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"102 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140632188","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Renuka Shanmugam, Reuben Anderson, Anja H Schiemann, Evelyn Sattlegger
The protein kinase Gcn2 and its effector protein Gcn1 are part of the general amino acid control signalling (GAAC) pathway best known in yeast for its function in maintaining amino acid homeostasis. Under amino acid limitation, Gcn2 becomes activated, subsequently increasing the levels of phosphorylated eIF2α (eIF2α-P). This leads to the increased translation of transcriptional regulators, such as Gcn4 in yeast and ATF4 in mammals, and subsequent re-programming of the cell's gene transcription profile, thereby allowing cells to cope with starvation. Xrn1 is involved in RNA decay, quality control and processing. We found that Xrn1 co-precipitates Gcn1 and Gcn2, suggesting that these three proteins are in the same complex. Growth under starvation conditions was dependent on Xrn1 but not on Xrn1-ribosome association, and this correlated with reduced eIF2α-P levels. Constitutively active Gcn2 leads to a growth defect due to eIF2α-hyperphosphorylation, and we found that this phenotype was independent of Xrn1, suggesting that xrn1 deletion does not enhance eIF2α de-phosphorylation. Our study provides evidence that Xrn1 is required for efficient Gcn2 activation, directly or indirectly. Thus, we have uncovered a potential new link between RNA metabolism and the GAAC.
{"title":"Evidence that Xrn1 is in complex with Gcn1, and is required for full levels of eIF2α phosphorylation.","authors":"Renuka Shanmugam, Reuben Anderson, Anja H Schiemann, Evelyn Sattlegger","doi":"10.1042/BCJ20220531","DOIUrl":"10.1042/BCJ20220531","url":null,"abstract":"<p><p>The protein kinase Gcn2 and its effector protein Gcn1 are part of the general amino acid control signalling (GAAC) pathway best known in yeast for its function in maintaining amino acid homeostasis. Under amino acid limitation, Gcn2 becomes activated, subsequently increasing the levels of phosphorylated eIF2α (eIF2α-P). This leads to the increased translation of transcriptional regulators, such as Gcn4 in yeast and ATF4 in mammals, and subsequent re-programming of the cell's gene transcription profile, thereby allowing cells to cope with starvation. Xrn1 is involved in RNA decay, quality control and processing. We found that Xrn1 co-precipitates Gcn1 and Gcn2, suggesting that these three proteins are in the same complex. Growth under starvation conditions was dependent on Xrn1 but not on Xrn1-ribosome association, and this correlated with reduced eIF2α-P levels. Constitutively active Gcn2 leads to a growth defect due to eIF2α-hyperphosphorylation, and we found that this phenotype was independent of Xrn1, suggesting that xrn1 deletion does not enhance eIF2α de-phosphorylation. Our study provides evidence that Xrn1 is required for efficient Gcn2 activation, directly or indirectly. Thus, we have uncovered a potential new link between RNA metabolism and the GAAC.</p>","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":" ","pages":"481-498"},"PeriodicalIF":4.1,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11088878/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140027295","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wilbourn, Barry, Nesbeth, Darren N., Wainwright, Linda J., Field, Mark C.
The authors of the original article “Proteasome and thiol involvement in quality control of glycosylphosphatidylinositol anchor addition” DOI: 10.1042/bj3320111: Wilbourn et al., Biochem. J.332, 111–118 (1998) would like to correct Figure 5 of this article. After publication, a reader identified that Figure 5 contained a duplicated Western blot image in panel ‘B’ between the “28” and “29” experimental groups. The authors confirmed that the “28” Western blot image was inadvertently duplicated and re-used for the
{"title":"Correction: Proteasome and thiol involvement in quality control of glycosylphosphatidylinositol anchor addition","authors":"Wilbourn, Barry, Nesbeth, Darren N., Wainwright, Linda J., Field, Mark C.","doi":"10.1042/bj3320111_cor","DOIUrl":"https://doi.org/10.1042/bj3320111_cor","url":null,"abstract":"The authors of the original article “Proteasome and thiol involvement in quality control of glycosylphosphatidylinositol anchor addition” DOI: 10.1042/bj3320111: Wilbourn et al., Biochem. J.332, 111–118 (1998) would like to correct Figure 5 of this article. After publication, a reader identified that Figure 5 contained a duplicated Western blot image in panel ‘B’ between the “28” and “29” experimental groups. The authors confirmed that the “28” Western blot image was inadvertently duplicated and re-used for the ","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"2013 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140547508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Respiratory complex I is a redox-driven proton pump. Several high-resolution structures of complex I have been determined providing important information about the putative proton transfer paths and conformational transitions that may occur during catalysis. However, how redox energy is coupled to the pumping of protons remains unclear. In this article, we review biochemical, structural and molecular simulation data on complex I and discuss several coupling models, including the key unresolved mechanistic questions. Focusing both on the quinone-reductase domain as well as the proton-pumping membrane-bound domain of complex I, we discuss a molecular mechanism of proton pumping that satisfies most experimental and theoretical constraints. We suggest that protonation reactions play an important role not only in catalysis, but also in the physiologically-relevant active/deactive transition of complex I.
呼吸复合体 I 是一种氧化还原驱动的质子泵。目前已经确定了多个 I 号复合体的高分辨率结构,提供了有关催化过程中可能发生的质子传递路径和构象转变的重要信息。然而,氧化还原能量如何与质子泵结合仍不清楚。在本文中,我们回顾了复合物 I 的生化、结构和分子模拟数据,并讨论了几种耦合模型,包括尚未解决的关键机制问题。我们以醌还原酶结构域和复合物 I 的质子泵膜结合结构域为重点,讨论了一种满足大多数实验和理论约束条件的质子泵的分子机制。我们认为质子化反应不仅在催化过程中起着重要作用,而且在与生理相关的复合物 I 的活性/非活性转换过程中也起着重要作用。
{"title":"Long-range electron proton coupling in respiratory complex I — insights from molecular simulations of the quinone chamber and antiporter-like subunits","authors":"Djurabekova, Amina, Lasham, Jonathan, Zdorevskyi, Oleksii, Zickermann, Volker, Sharma, Vivek","doi":"10.1042/bcj20240009","DOIUrl":"https://doi.org/10.1042/bcj20240009","url":null,"abstract":"Respiratory complex I is a redox-driven proton pump. Several high-resolution structures of complex I have been determined providing important information about the putative proton transfer paths and conformational transitions that may occur during catalysis. However, how redox energy is coupled to the pumping of protons remains unclear. In this article, we review biochemical, structural and molecular simulation data on complex I and discuss several coupling models, including the key unresolved mechanistic questions. Focusing both on the quinone-reductase domain as well as the proton-pumping membrane-bound domain of complex I, we discuss a molecular mechanism of proton pumping that satisfies most experimental and theoretical constraints. We suggest that protonation reactions play an important role not only in catalysis, but also in the physiologically-relevant active/deactive transition of complex I.","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"124 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140349186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Editorial Office has been made aware of potential issues surrounding the scientific validity of this paper, hence has issued an expression of concern to notify readers whilst the Editorial Office investigates. It has been noted that there seems to be a partial duplication between Figure 4C PAR2-OE control panel and Figure 4E Si-NC MHY1485 panel, as well as a duplication between Figure 7B Sham and UUO+rapa panels.
{"title":"Expression of Concern: Protease-activated receptor-2 promotes kidney tubular epithelial inflammation by inhibiting autophagy via the PI3K/Akt/mTOR signalling pathway","authors":"Du, Chunyang, Zhang, Tao, Xiao, Xia, Shi, Yonghong, Duan, Huijun, Ren, Yunzhuo","doi":"10.1042/bcj20170272_eoc","DOIUrl":"https://doi.org/10.1042/bcj20170272_eoc","url":null,"abstract":"The Editorial Office has been made aware of potential issues surrounding the scientific validity of this paper, hence has issued an expression of concern to notify readers whilst the Editorial Office investigates. It has been noted that there seems to be a partial duplication between Figure 4C PAR2-OE control panel and Figure 4E Si-NC MHY1485 panel, as well as a duplication between Figure 7B Sham and UUO+rapa panels.","PeriodicalId":8825,"journal":{"name":"Biochemical Journal","volume":"36 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-04-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140545046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}