Journal of Biological Chemistry最新文献_第10页

The Sotos syndrome gene Nsd1 safeguards developmental gene enhancers poised for transcription by maintaining the precise deposition of histone methylation. 索托斯综合征基因 Nsd1 通过保持组蛋白甲基化的精确沉积，保护了准备转录的发育基因增强子。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-19 DOI: 10.1016/j.jbc.2025.108423

Jie Li, Zhucui Li, Jiekai Yin, Yinsheng Wang, Deyou Zheng, Ling Cai, Gang Greg Wang

{"title":"The Sotos syndrome gene Nsd1 safeguards developmental gene enhancers poised for transcription by maintaining the precise deposition of histone methylation.","authors":"Jie Li, Zhucui Li, Jiekai Yin, Yinsheng Wang, Deyou Zheng, Ling Cai, Gang Greg Wang","doi":"10.1016/j.jbc.2025.108423","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108423","url":null,"abstract":"Germline haploinsufficiency of NSD1 is implicated as the etiology of Sotos syndrome; however, the underlying mechanism remains far from being clear. Here, we use mouse embryonic stem cell (mESC) differentiation as a model system to address this question. We found Nsd1 to be indispensable for the faithful differentiation of mESCs into three primary germ layers, particularly, various meso-endodermal cell lineages related to development of the heart and the skeletal system. Time-course transcriptomic profiling following the mESC differentiation revealed that Nsd1 not only facilitates the basal expression but also permits the differentiation-accompanied rapid induction of a suite of meso-endoderm lineage-specifying transcription factor (TF) genes such as T and Gata4. Mechanistically, Nsd1 directly occupies putative distal enhancers of the lineage TF genes under the pluripotent cell state, where it deposits H3K36me2 to antagonizes the excessive H3K27me3 and maintain the basal H3K27ac level, thereby safeguarding these gene enhancers at a primed state that responds readily to differentiation cues. In agreement, gene rescue assays using the Nsd1 knockout mESCs showed that the H3K36me2 catalysis by Nsd1 requires several functional modules within Nsd1 (namely, PHD1-4, PWWP2 and SET) to a similar degree. Disruption of either one of these Nsd1 modules severely abrogated H3K36me2 in mESCs and significantly impaired appropriate induction of developmental genes upon mESC differentiation. Altogether, our study provides novel molecular insight into how the NSD1 perturbation derails normal development and causes the disease.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108423"},"PeriodicalIF":4.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143674030","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

ATP synthesis of Enterococcus hirae V-ATPase driven by sodium motive force. 由钠动力驱动的平肠球菌 V-ATP 酶的 ATP 合成。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-19 DOI: 10.1016/j.jbc.2025.108422

Akihiro Otomo, Lucy Gao Hui Zhu, Yasuko Okuni, Mayuko Yamamoto, Ryota Iino

{"title":"ATP synthesis of Enterococcus hirae V-ATPase driven by sodium motive force.","authors":"Akihiro Otomo, Lucy Gao Hui Zhu, Yasuko Okuni, Mayuko Yamamoto, Ryota Iino","doi":"10.1016/j.jbc.2025.108422","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108422","url":null,"abstract":"V-ATPases generally function as ion pumps driven by ATP hydrolysis in the cell, but their capability of ATP synthesis remains largely unexplored. Here we show ATP synthesis of Na+-transporting Enterococcus hirae V-ATPase (EhVoV1) driven by electrochemical potential gradient of Na+ across the membrane (sodium motive force, smf). We reconstituted EhVoV1 into liposome and performed a luciferin/luciferase-based assay to analyze ATP synthesis quantitatively. Our result demonstrates that EhVoV1 synthesizes ATP with a rate of 4.7 s-1 under high smf (269.3 mV). The Michaelis constants for ADP (21 μM) and inorganic phosphate (2.1 mM) in ATP synthesis reaction were comparable to those for ATP synthases, suggesting similar substrate affinities among rotary ATPases regardless of their physiological functions. Both components of smf, Na+ concentration gradient across the membrane (ΔpNa) and membrane potential (Δψ), contributed to ATP synthesis, with ΔpNa showing a slightly larger impact. At the equilibrium points where smf and Gibbs free energy of ATP synthesis are balanced, EhVoV1 showed reversible reactions between ATP synthesis and hydrolysis. The obtained Na+/ATP ratio (3.2 ± 0.4) closely matched the value expected from the structural symmetry ratio between EhVo and EhV1 (10/3 = 3.3), indicating tight coupling between ATP synthesis/hydrolysis and Na+ transport. These results reveal inherent functional reversibility of EhVoV1. We propose that physiological function of EhVoV1in vivo is determined by relatively small smf against large Gibbs free energy of ATP synthesis, in addition to the absence of inhibitory mechanisms of ATP hydrolysis which are known for ATP synthases.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108422"},"PeriodicalIF":4.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143673967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Androgen receptor-induced lncRNA SOX2-OT promotes triple-negative breast cancer tumorigenesis via targeting miR-320a-5p/CCR5 axis. 雄激素受体诱导的lncRNA SOX2-OT通过靶向miR-320a-5p/CCR5轴促进三阴性乳腺癌的肿瘤发生。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-19 DOI: 10.1016/j.jbc.2025.108428

Yixuan Hu, Jin Bian, Weiwei Chen, Junfeng Shi, Xiaowei Wei, Yueyao Du, Wenwen Zhang

{"title":"Androgen receptor-induced lncRNA SOX2-OT promotes triple-negative breast cancer tumorigenesis via targeting miR-320a-5p/CCR5 axis.","authors":"Yixuan Hu, Jin Bian, Weiwei Chen, Junfeng Shi, Xiaowei Wei, Yueyao Du, Wenwen Zhang","doi":"10.1016/j.jbc.2025.108428","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108428","url":null,"abstract":"Our previous study showed that androgen receptor (AR) promotes triple-negative breast cancer (TNBC) cells tumorigenesis, but the underlying mechanisms remain unclear. Herein, using microarray analysis of lncRNA expression profiles, we identified an AR-related lncRNA SOX2-OT in TNBC. We found that AR could promote TNBC tumorigenesis by acting as a transcription factor to activate the expression of SOX2-OT. Mechanistic analysis demonstrated that SOX2-OT serves as a molecular sponge for miR-320a-5p to regulate the expression of CCR5. In addition, SOX2-OT promotes TNBC cell proliferation and inhibits apoptosis in a miR-320a-5p-dependent manner. Using a xenograft mouse model, we found SOX2-OT/CCR5 axis could promote TNBC tumorigenesis in vivo. Importantly, the AR/SOX2-OT/miR-320a-5p/CCR5 axis is manifested in the tissues of 165 TNBC patients. Collectively, our results suggest that SOX2-OT can regulate AR-induced TNBC tumorigenesis through the miR-320a-5p/CCR5 signaling axis, and reveal the great potential of targeting SOX2-OT for the treatment of TNBC patients.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108428"},"PeriodicalIF":4.0,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143673966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Optogenetic tools for inducing organelle membrane rupture. 诱导细胞器膜破裂的光遗传学工具。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.jbc.2025.108421

Yuto Nagashima, Tomoya Eguchi, Ikuko Koyama-Honda, Noboru Mizushima

{"title":"Optogenetic tools for inducing organelle membrane rupture.","authors":"Yuto Nagashima, Tomoya Eguchi, Ikuko Koyama-Honda, Noboru Mizushima","doi":"10.1016/j.jbc.2025.108421","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108421","url":null,"abstract":"Disintegration of organelle membranes induces various cellular responses and has pathological consequences, including autoinflammatory diseases and neurodegeneration. Establishing methods to induce membrane rupture of specific organelles is essential to analyze the downstream effects of membrane rupture; however, the spatiotemporal induction of organelle membrane rupture remains challenging. Here, we develop a series of optogenetic tools to induce organelle membrane rupture by using engineered Bcl-2-associated X protein (BAX), which primarily functions to form membrane pores in the outer mitochondrial membrane (OMM) during apoptosis. When BAX is forced to target mitochondria, lysosomes, or the endoplasmic reticulum (ER) by replacing its C-terminal transmembrane domain (TMD) with organelle-targeting sequences, the BAX mutants rupture their targeted membranes. To regulate the activity of organelle-targeted BAX, the photosensitive light-oxygen-voltage-sensing 2 (LOV2) domain is fused to the N-terminus of BAX. The resulting LOV2-BAX fusion protein exhibits blue light-dependent membrane-rupture activity on various organelles, including mitochondria, the ER, and lysosomes. Thus, LOV2-BAX enables spatiotemporal induction of membrane rupture across a broad range of organelles, expanding research opportunities on the consequences of organelle membrane disruption.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108421"},"PeriodicalIF":4.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ninein isoform contributions to intracellular processes and macrophage immune function. 九蛋白异构体对细胞内过程和巨噬细胞免疫功能的贡献。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.jbc.2025.108419

Safia Omer, Elizabeth Persaud, Safia Mohammad, Bolu Ayo-Farinloye, Rebecca E Heineman, Emily Wellwood, G Adam Mott, Rene E Harrison

{"title":"Ninein isoform contributions to intracellular processes and macrophage immune function.","authors":"Safia Omer, Elizabeth Persaud, Safia Mohammad, Bolu Ayo-Farinloye, Rebecca E Heineman, Emily Wellwood, G Adam Mott, Rene E Harrison","doi":"10.1016/j.jbc.2025.108419","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108419","url":null,"abstract":"Ninein is a multifunctional protein, involved in microtubule (MT) organization and dynein/dynactin complex recruitment and activation. Several isoforms of ninein have been identified in various tissues, however, their relative contribution(s) are not clear. Here, we identify two ninein isoforms in mouse macrophages with distinct C-termini and disproportionate expression levels; a canonical ninein (nineinCAN) isoform and ninein isoform 2 (nineinISO2). Analysis of ninein pre-mRNA exon-intron boundaries revealed that nineinISO2 transcript is likely generated by two alternative splicing site selection events predicted to result in a distinct 3D structure compared to nineinCAN. We used selective and total protein knockdown experiments to assess intracellular and functional roles of ninein in macrophages. Live cell imaging analyses of macrophages implicated both isoforms in regulating cell proliferation. MT regrowth following nocodazole depolymerization showed that both isoforms contributed to MT nucleation and structural integrity of the centrosome, as cells lacking nineinCAN or nineinISO2 contained multiple ectopic γ-tubulin foci. However, nineinCAN, but not nineinISO2, was important for the separation of duplicated centrosomes during cell division. Despite a requirement of both ninein isoforms to recruit dynein/dynactin to the centrosome, only nineinCAN was required for Golgi positioning and morphology, a dynein-dependent event. We additionally found that nineinISO2 was the primary isoform required for F-actin recruitment during internalization of IgG-opsonized particles. Our study indicates that alternative splicing promotes both redundant and differential activities for ninein in MT organization, organelle positioning and macrophage function.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108419"},"PeriodicalIF":4.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Carbohydrate deacetylase, a key enzyme in oxidative chitin degradation, is evolutionarily linked to amino acid deacetylase. 碳水化合物去乙酰化酶是氧化几丁质降解的关键酶，与氨基酸去乙酰化酶进化相关。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.jbc.2025.108420

Jing-Ping Wang, Xiang-Ming Zhao, Xiao-Lei Liu, Wen-Xin Jiang, Chao Gao, Hai-Yan Cao, Hai-Tao Ding, Qi-Long Qin, Xiu-Lan Chen, Yu-Zhong Zhang, Ping-Yi Li

{"title":"Carbohydrate deacetylase, a key enzyme in oxidative chitin degradation, is evolutionarily linked to amino acid deacetylase.","authors":"Jing-Ping Wang, Xiang-Ming Zhao, Xiao-Lei Liu, Wen-Xin Jiang, Chao Gao, Hai-Yan Cao, Hai-Tao Ding, Qi-Long Qin, Xiu-Lan Chen, Yu-Zhong Zhang, Ping-Yi Li","doi":"10.1016/j.jbc.2025.108420","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108420","url":null,"abstract":"The microbial oxidative cleavage of chitin, the second most abundant biopolymer in nature, generates a substantial amount of oxidized amino sugar, 2-(acetylamino)-2-deoxy-D-gluconic acid (GlcNAc1A). The catabolism of GlcNAc1A is key to the oxidative chitin degradation pathway. However, the molecular mechanism and evolution underlying this pathway remain elusive. Here, we target OngB, which initiates the GlcNAc1A catabolism, to explore the molecular mechanism driving the evolution of this process. We characterized PpOngB (the OngB from Pseudoalteromonas prydzensis ACAM 620) and its homologs as specific deacetylases for GlcNAc1A and solved the structures of wild-type PpOngB and its inactive mutant in complex with GlcNAc1A. Structural, mutational and biochemical analyses revealed that PpOngB utilizes a D-aminoacylase-like (β/α)8-barrel fold to deacetylate GlcNAc1A in a metal-dependent manner. PpOngB and its homologs significantly differ from other known carbohydrate de-N-acetylases in sequences, substrate specificities and structures. Phylogenetic analysis indicated that PpOngB and its homologs represent a new carbohydrate de-N-acetylase family, forming a sister group of D-aminoacylases involved in the catabolism of N-acetyl-D-amino acids. Further structural analysis suggested that GlcNAc1A deacetylases likely evolved from an ancestral D-aminoacylase, undergoing structural and electrostatic modifications in the catalytic cavity to hydrolyze GlcNAc1A. This study provides insights into the catalytic mechanism and the divergent evolution of GlcNAc1A deacetylases, advancing our understanding of oxidative chitin degradation.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108420"},"PeriodicalIF":4.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

MUTANT PROTEIN CHEMICAL RESCUE: FROM MECHANISMS TO THERAPEUTICS. 突变蛋白化学救援：从机制到治疗。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.jbc.2025.108417

Timothy R O'Meara, Brad A Palanski, Maggie Chen, Yingfeng Qiao, Philip A Cole

{"title":"MUTANT PROTEIN CHEMICAL RESCUE: FROM MECHANISMS TO THERAPEUTICS.","authors":"Timothy R O'Meara, Brad A Palanski, Maggie Chen, Yingfeng Qiao, Philip A Cole","doi":"10.1016/j.jbc.2025.108417","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108417","url":null,"abstract":"Chemical rescue is a technique for restoring the activity and/or structure of an engineered or naturally occurring (e.g., disease-associated) mutant protein by the introduction of a \"molecular crutch\" that abrogates the mutation's effect. This method was developed about four decades ago to facilitate mechanistic analysis of enzymes. Since then, a variety of purified proteins inactivated by site-directed mutagenesis have been successfully rescued by substrate moieties or exogenous small molecules, an approach that has continued to serve as an important tool for mechanistic enzymologists. More recently, chemical rescue has been applied to activate engineered proteins in intact biological systems for phenotypic and pathway-level analyses. There is growing interest in therapeutic applications of chemical rescue to correct protein mutations that give rise to human diseases. In this review, we first contextualize chemical rescue and discuss its utility in protein mechanistic analysis. Second, we review the advantages and caveats associated with using this approach to study protein function within biological settings. Third, we provide an overview of efforts to develop folding correctors that restore the proper function of disease-associated protein mutants. To conclude, future directions and challenges for the chemical rescue field are discussed.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108417"},"PeriodicalIF":4.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stress-induced changes in endogenous TP53 mRNA 5' regulatory region. 压力诱导的内源性 TP53 mRNA 5' 调控区的变化

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-18 DOI: 10.1016/j.jbc.2025.108418

Jin Yeong Kim, Alexandra Furney, Brittany Benner, Arnab Sengupta

{"title":"Stress-induced changes in endogenous TP53 mRNA 5' regulatory region.","authors":"Jin Yeong Kim, Alexandra Furney, Brittany Benner, Arnab Sengupta","doi":"10.1016/j.jbc.2025.108418","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108418","url":null,"abstract":"Tumor suppressor protein p53 is regulated in a number of ways, including during initiation of TP53 mRNA translation. The 5' end of TP53 mRNA contains regulatory structures that enable non-canonical initiation using mechanisms that remain poorly described. Here we analyze per-nucleotide reactivity changes in the 5' end secondary structure of TP53 mRNA under in-cell conditions using A549 human lung carcinoma cells. We first construct a cell-free secondary structure model using SHAPE reagent 5NIA (5-nitroisatoic anhydride) on gently extracted and deproteinated RNA. We observe previously described regulatory features of the TP53 mRNA 5' end including two motifs which we refer to as long stem-loop (LSL) and short stem-loop (SSL), respectively. We observe a domain-forming helix that groups LSL and SSL, forming a three-helix junction. Applying in-cell SHAPE-MaP, we assess reactivity profiles with unstressed cells and with chemically induced stress conditions expected to stimulate TP53 cap-independent translation. We analyze the effects of etoposide-induced DNA damage, CoCl2-induced hypoxia, and 5' cap inhibition with 4EGI-1 treatment. Identifying stress-associated changes in the TP53 5' end may help elucidate the role of regulatory RNA structure in cap-independent translation. Using ΔSHAPE we identify in-cell protection sites that correspond with previously described RNA-protein binding sites on the apical loops of LSL and SSL. Furthermore, we identify several other potential interaction sites, some associated with specific types of stress. Some noteworthy changes include ΔSHAPE sites proximal to the start codons, at the three-helix junction, and on the domain-forming helix. We summarize potential interactions on the cell-free secondary structure model.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108418"},"PeriodicalIF":4.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143669900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic interactions of dimeric hub proteins underlie their diverse functions and structures: A comparative analysis of 14-3-3 and LC8. 二聚体枢纽蛋白的动态相互作用是其不同功能和结构的基础：14-3-3和LC8的比较分析。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-17 DOI: 10.1016/j.jbc.2025.108416

Jesse Howe, Elisar J Barbar

{"title":"Dynamic interactions of dimeric hub proteins underlie their diverse functions and structures: A comparative analysis of 14-3-3 and LC8.","authors":"Jesse Howe, Elisar J Barbar","doi":"10.1016/j.jbc.2025.108416","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108416","url":null,"abstract":"Hub proteins interact with a host of client proteins and regulate multiple cellular functions. Dynamic hubs have a single binding interface for one client at a time resulting in competition among clients with the highest affinity. Dynamic dimeric hubs with two identical sites bind either two different client proteins or two chains of the same client to form homogenous complexes and could also form heterogeneous mixtures of interconverting complexes. Here, we review the interactions of the dimeric hubs 14-3-3 and LC8. 14-3-3 is a phosphoserine/threonine binding protein involved in structuring client proteins and regulating their phosphorylation. LC8 is involved in promoting dimerization of client peptides and rigidification of their disordered regions. Both 14-3-3 and LC8 are essential genes, with 14-3-3 playing a crucial role in apoptosis and cell cycle regulation, while LC8 is critical for assembly of proteins involved in transport, DNA repair, and transcription. Interestingly, both protein dimers can dissociate by phosphorylation, which results in their interactome-wide changes. Their interactions are also regulated by phosphorylation of their clients. Both form heterogeneous complexes with various functions including phase separation, signaling, and viral hijacking where they restrict the conformational heterogeneity of their dimeric clients that bind nucleic acids. This comparative analysis highlights the importance of dynamic protein-protein interactions in the diversity of functions of 14-3-3 and LC8 and how small differences in structures of interfaces explain why 14-3-3 is primarily involved in regulation of phosphorylation states while LC8 is primarily involved in regulation of assembly of large dynamic complexes.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108416"},"PeriodicalIF":4.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cryo-EM Structures Define the Electron Bifurcating Flavobicluster and Ferredoxin Binding Site in an Archaeal Nfn-Bfu Transhydrogenase. 古细菌Nfn-Bfu转氢酶中电子分岔黄簇和铁氧还蛋白结合位点的低温电镜结构。

IF 4 2区生物学

Journal of Biological Chemistry Pub Date : 2025-03-17 DOI: 10.1016/j.jbc.2025.108410

Xiansha Xiao, Gerrit J Schut, Xiang Feng, Diep M N Nguyen, Haiyan Huang, Shuning Wang, Huilin Li, Michael W W Adams

{"title":"Cryo-EM Structures Define the Electron Bifurcating Flavobicluster and Ferredoxin Binding Site in an Archaeal Nfn-Bfu Transhydrogenase.","authors":"Xiansha Xiao, Gerrit J Schut, Xiang Feng, Diep M N Nguyen, Haiyan Huang, Shuning Wang, Huilin Li, Michael W W Adams","doi":"10.1016/j.jbc.2025.108410","DOIUrl":"https://doi.org/10.1016/j.jbc.2025.108410","url":null,"abstract":"Flavin-based electron bifurcation couples exergonic and endergonic redox reactions in one enzyme complex to circumvent thermodynamic barriers and minimize free energy loss. Two unrelated enzymes designated NfnSL and NfnABC catalyze the NADPH-dependent reduction of ferredoxin and NAD. Bifurcation by NfnSL resides with a single FAD but the bifurcation mechanism of NfnABC, which represents the diverse and ubiquitous Bfu enzyme family, is completely different and largely unknown. Using cryo-EM structures of an archaeal NfnABC, we show that its bifurcation site is a flavobicluster consisting of FMN, one [4Fe-4S] and one [2Fe-2S] cluster where zinc atoms replace two additional clusters previously identified in other Bfu enzymes. NADH binds to the flavobicluster site of NfnABC and induces conformational changes that allow ferredoxin to bind between the C-terminal domains of NfnC and NfnB. Site-directed mutational analyses support the proposed mechanism that is likely conserved in all members of the Bfu enzyme family.","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":" ","pages":"108410"},"PeriodicalIF":4.0,"publicationDate":"2025-03-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143663293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0