Journal of Biological Chemistry最新文献

{"title":"Alpha-1 antitrypsin inhibits pertussis toxin.","authors":"Stefanie Lietz, Anja Sommer, Lena-Marie Sokolowski, Carolin Kling, Armando A Rodriguez Alfonso, Nico Preising, Daniel Alpízar-Pedraza, Jaylyn King, Lisa Streit, Bernd Schröppel, Rene van Erp, Eberhard Barth, Marion Schneider, Jan Münch, Jens Michaelis, Ludger Ständker, Sebastian Wiese, Holger Barth, Arto T Pulliainen, Karen Scanlon, Katharina Ernst","doi":"10.1016/j.jbc.2024.107950","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107950","url":null,"abstract":"<p><p>Pertussis (whooping cough) is a vaccine-preventable but re-emerging, highly infectious respiratory disease caused by Bordetella pertussis. There are currently no effective treatments for pertussis, complicating care for non-vaccinated individuals, especially newborns. Disease manifestations are predominantly caused by pertussis toxin (PT), a pivotal virulence factor classified as an ADP-ribosylating AB-type protein toxin. In this work, an unbiased approach using peptide libraries, bioassay-guided fractionation and mass spectrometry revealed α₁-antitrypsin (α₁AT) as a potent PT inhibitor. Biochemistry-, cell culture- and molecular modeling-based in vitro experimentation demonstrated that the α₁AT mode of action is based on blocking PT-binding to the host target cell surface. In the infant mouse model of severe pertussis, α₁AT expression was reduced upon infection. Further, systemic administration of α₁AT significantly reduced B. pertussis-induced leukocytosis, which is a hallmark of infant infection and major risk factor for fatal pertussis. Taken together our data demonstrates that α₁AT is a novel PT inhibitor and that further evaluation and development of α₁AT as a therapeutic agent for pertussis is warranted. Importantly, purified α₁AT is already in use clinically as an intravenous augmentation therapy for those with genetic α₁AT deficiency and could be repurposed to clinical management of pertussis.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557809","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}

{"title":"Loss of Hdac4 in Osteoprogenitors Impairs Postnatal Trabecular and Cortical Bone Formation, Resulting in a Dwarfism and Osteopenia Phenotype in Mice.","authors":"YunFei Wang, Raorao Zhou, Zhengquan Dong, Wenting Wang, Li Guo, Jian Sun, Xueqin Rong, Pengcui Li","doi":"10.1016/j.jbc.2024.107941","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107941","url":null,"abstract":"<p><p>HDAC4 is a class II histone deacetylation protein with a well-characterized role in chondrocyte differentiation and skeletal development, and dysregulated expression or haploinsufficiency of Hdac4 leads to skeletal formation and malformation disorders. The early lethality of hdac4 ablation mice hindered further investigation of its role in postnatal bone growth and development. Therefore, this study aims to investigate the significant role of Hdac4 in postnatal endochondral bone development using two mouse models with conditional deletion of Hdac4 in Sp7-expressing osteoprogenitors or chondrocytes and monitored postnatal bone development. The phenotype of Acan-CreERT2; Hdac4^fl/fl mice largely resembled that of conventional Hdac4^-/- mice. But phenotypic characterizations of mice with Hdac4 inactivation in Sp7-expressing osteoprogenitors (Sp7-Cre; Hdac4^fl/fl) showed dwarfism with body and limb shortening and remarkable skeletal defects. Micro-computed tomography analysis of tibias further demonstrated that loss of Hdac4 expression impaired bone formation and microarchitecture, mainly characterized by dysplasia of trabecular and cortical bone in young mice. Our in vivo and in vitro data support a crucial role for Hdac4 in regulating osteoblast proliferation and differentiation, bone matrix protein production, angiogenesis, and ultimately trabecular and cortical bone formation. Moreover, RNA-seq analysis implicated Hdac4 in the regulation of key genes and pathways necessary to affect the accumulation of extracellular matrix, biological processes related to signal transduction, and skeletal growth. Collectively, our data show that postnatal expression of Hdac4 in Sp7-expressing osteoprogenitors provides essential regulatory oversight of endochondral bone formation, bone morphology, and homeostasis.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557812","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}

{"title":"Structural profiles of the full phagocyte NADPH oxidase unveiled by combining computational biology and experimental knowledge.","authors":"Sana Aimeur, Burcu Aykac Fas, Xavier Serfaty, Hubert Santuz, Sophie Sacquin-Mora, Tania Bizouarn, Antoine Taly, Laura Baciou","doi":"10.1016/j.jbc.2024.107943","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107943","url":null,"abstract":"<p><p>The phagocyte NADPH oxidase (NOX2) is an enzyme, crucial for innate immune defense, producing reactive oxygen species necessary for pathogen destruction. Its activation requires the assembly of soluble proteins (p47^phox, p40^phox, p67^phox, and Rac) with the membrane-bound flavocytochrome b₅₅₈ (cytb₅₅₈). We combined circular-dichroism analyses, with decades of experimental data, to filter structural models of the NADPH oxidase complex generated by the artificial intelligence program AlphaFold2 (AF2). The predicted patterns tend to closely resemble the active states of the proteins, as shown by the compact structure of the cytb₅₅₈, whose dehydrogenase domain is stabilized closer to the membrane. The modeling of the interaction of p47^phox with cytb₅₅₈, which is the initial assembly and activation steps of the NADPH oxidase, enables us to describe how the C-terminus of p47^phox interacts with the cytb₅₅₈. Combining the AF2 cytb₅₅₈ -p47^phox model and its classical molecular dynamics simulations, we highlighted new hydrophobic lipid insertions of p47^phox, particularly at residues Trp80-Phe81 of its PX domain. The AF2 models also revealed the implications of intrinsically disordered regions, such as the fragment between the PX domain and the SH3 regions of p47^phox, in ensuring distant protein-protein and membrane-protein interactions. Finally, the AF2 prediction of the cytb₅₅₈-Trimera model highlighted the importance of leaving Rac1 as a separate protein to reach an active state of the NADPH oxidase complex. Altogether, our step-by-step approach provides a structural model of the active complex showing how disordered regions and specific lipid and protein interactions can enable and stabilize the multi-subunit assembly.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557879","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}

{"title":"CK-666 protects against ferroptosis and renal ischemia-reperfusion injury through a microfilament-independent mechanism.","authors":"Qian Hu, Yanan Zhao, Wan-Yang Sun, Zexian Ou, Wentao Duan, Zeyu Qiu, Yuanlong Ge, Daolin Tang, Tianfeng Chen, Xiang Cheng, Rong-Rong He, Shu Wu, Zhenyu Ju","doi":"10.1016/j.jbc.2024.107942","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107942","url":null,"abstract":"<p><p>Ferroptosis is a type of regulated cell death driven by iron-dependent accumulation of lipid peroxidation, exhibiting unique morphological changes. While actin microfilaments are crucial for various cellular processes, including morphogenesis, motility, endocytosis, and cell death, their role in ferroptosis remains unclear. Here, our study reveals that actin microfilaments undergo remodeling and disassembly during ferroptosis. Interestingly, inhibitors that target actin microfilament remodeling do not affect cell sensitivity to ferroptosis, with the exception of CK-666 and its structural analogue CK-636. Mechanistically, CK-666 attenuates ferroptosis independently of its canonical function in inhibiting the Arp2/3 complex. Further investigation revealed that CK-666 modulates the ferroptotic transcriptome, prevents lipid degradation, and diminishes lipid peroxidation. In addition, CK-666 does not impact the labile iron pool within cells, nor does the inhibition of FSP1 impact its anti-ferroptosis activity. Notably, the results of DPPH assay and liposome leakage assay suggest that CK-666 mitigates ferroptosis by directly eliminating lipid peroxidation. Importantly, CK-666 significantly ameliorated renal ischemia-reperfusion injury and ferroptosis in renal tissue, underscoring its potential therapeutic impact.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557810","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}

{"title":"N-glycan Core Tri-fucosylation Requires Golgi α-mannosidase III Activity that Impacts Nematode Growth and Behaviour.","authors":"Jonatan Kendler, Florian Wӧls, Saurabh Thapliyal, Elsa Arcalis, Hanna Gabriel, Sascha Kubitschek, Daniel Malzl, Maria R Strobl, Dieter Palmberger, Thomas Luber, Carlo Unverzagt, Katharina Paschinger, Dominique A Glauser, Iain B H Wilson, Shi Yan","doi":"10.1016/j.jbc.2024.107944","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107944","url":null,"abstract":"<p><p>N-glycans with complex core chitobiose modifications (CCMs) are observed in various free-living and parasitic nematodes but are absent in mammals. Using Caenorhabditis elegans as a model, we demonstrated that the core N-acetylglucosamine (GlcNAc) residues are modified by three fucosyltransferases, namely FUT-1, FUT-6 and FUT-8. Interestingly, FUT-6 can only fucosylate N-glycans lacking the α1,6-mannose upper arm, indicating that a specific α-mannosidase is required to generate substrates for subsequent FUT-6 activity. By analysing the N-glycomes of aman-3 knockouts using offline HPLC-MALDI-TOF MS/MS, we observed that the absence of aman-3 abolishes α1,3-fucosylation of the distal GlcNAc of N-glycans, which suggests that AMAN-3 is the relevant mannosidase on whose action FUT-6 depends. Enzymatic characterisation of recombinant AMAN-3 and confocal microscopy studies using a knock-in strain (aman-3::eGFP) demonstrated a Golgi localisation. In contrast to the classical Golgi α-mannosidase II (AMAN-2), AMAN-3 displayed a cobalt-dependent α1,6-mannosidase activity towards N-glycans. Using AMAN-3 and other C. elegans glycoenzymes, we were able to mimic nematode N-glycan biosynthesis in vitro by remodelling a fluorescein conjugated-glycan and generate a tri-fucosylated structure. In addition, using a high-content computer-assisted C. elegans analysis platform, we observed that aman-3 deficient worms display significant developmental delays, morphological and behavioural alterations in comparison to the wild type. Our data demonstrated that AMAN-3 is a Golgi α-mannosidase required for core fucosylation of the distal GlcNAc of N-glycans. This enzyme is essential for the formation of the unusual tri-fucosylated CCMs in nematodes, which may play important roles in nematode development and behaviour.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142557814","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}

{"title":"The sodium-proton exchangers sNHE and NHE1 control plasma membrane hyperpolarization in mouse sperm.","authors":"Analia G Novero, Paulina Torres Rodríguez, José L De la Vega Beltrán, Liza J Schiavi-Ehrenhaus, Guillermina M Luque, Micaela Carruba, Cintia Stival, Iñaki Gentile, Carla Ritagliati, Celia M Santi, Takuya Nishigaki, Diego Krapf, Mariano G Buffone, Alberto Darszon, Claudia L Treviño, Dario Krapf","doi":"10.1016/j.jbc.2024.107932","DOIUrl":"10.1016/j.jbc.2024.107932","url":null,"abstract":"<p><p>Sperm capacitation is a complex process that takes place in the female reproductive tract and empowers mammalian sperm with the competence to fertilize an egg. It consists of an intricate cascade of events that can be mimicked in vitro through incubation in a medium containing essential components such as bicarbonate, albumin, Ca²⁺ and energy substrates, among others. Genetic and pharmacological studies have underscored the unique significance of the K⁺ channel SLO3 in membrane potential hyperpolarization, as evidenced by the infertility of mice lacking its expression. Notably, two key molecular events, sperm hyperpolarization and intracellular alkalinization, are central to the capacitation process. SLO₃ is activated by alkalinization. However, the molecular mechanisms responsible for intracellular alkalization and activation of SLO₃ are not completely understood. In this study, we examined the impact of Na⁺/H⁺ exchangers on mouse sperm membrane hyperpolarization during capacitation. Pharmacological inhibition of the NHE₁ exchanger blocked membrane hyperpolarization. A similar effect was observed in sperm deficient of the Ca²⁺ channel CatSper, because of NHE₁ not being activated by Ca²⁺. In addition, the sperm specific NHE (sNHE) KO, did not show membrane hyperpolarization upon capacitation or induction with cAMP analogues. Our results show that sNHE is dually modulated by cAMP and membrane hyperpolarization probably through its cyclic nucleotide binding domain and the voltage-sensor motif respectively. Together, sNHE and NHE1provide the alkalinization need for SLO₃ activation during capacitation.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545659","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}

{"title":"The GPCR adaptor protein Norbin controls the trafficking of C5aR1 and CXCR4 in mouse neutrophils.","authors":"Stephen A Chetwynd, Richard J Ward, Graeme Milligan, Heidi C E Welch","doi":"10.1016/j.jbc.2024.107940","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107940","url":null,"abstract":"<p><p>Norbin (Neurochondrin, NCDN) is a GPCR adaptor protein known for its importance in neuronal function. Norbin works by binding to numerous GPCRs, controlling their steady state trafficking and sometimes their agonist-induced internalisation, as well as their signalling. We recently showed that Norbin is expressed in neutrophils, limits the surface levels of the GPCRs C5aR1 and CXCR4 in neutrophils, and suppresses neutrophil-mediated innate immunity. Here, we identify C5aR1 and CXCR4 as direct Norbin interactors and used mice with myeloid-Norbin deficiency to investigate the role of Norbin in the trafficking of endogenous C5aR1 and CXCR4 in primary neutrophils by flow cytometry and cell fractionation. We show that Norbin mediates the agonist-induced internalisation of C5aR1 through a β-arrestin-dependent mechanism and limits the recycling of internalised C5aR1 and CXCR4 back to the cell surface. Norbin does not control the constitutive internalisation of C5aR1 and CXCR4, nor does it affect the agonist-induced internalisation of CXCR4. Norbin suppresses C5aR1 signalling in mouse neutrophils by limiting the C5a-stimulated membrane translocation of Tiam1, Vav, and PKCδ, and activation of Erk and p38 Mapk pathways, as well as Gα_i-dependent ROS production. Our study demonstrates how Norbin suppresses C5aR1 and CXCR4 function in neutrophils and increases our understanding of the mechanisms through which Norbin regulates GPCR trafficking generally, by identifying its importance in β-arrestin recruitment, β-arrestin dependent agonist-induced receptor internalisation, and receptor recycling.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545658","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}

{"title":"Natural volatiles preventing mosquito biting: an integrated screening platform for accelerated discovery of ORco antagonists.","authors":"Georgia Kythreoti, Trias Thireou, Christos Karoussiotis, Zafiroula Georgoussi, Panagiota Gv Liggri, Dimitrios P Papachristos, Antonios Michaelakis, Vasileios Karras, Spyros E Zographos, Stefan Schulz, Kostas Iatrou","doi":"10.1016/j.jbc.2024.107939","DOIUrl":"https://doi.org/10.1016/j.jbc.2024.107939","url":null,"abstract":"<p><p>Insect olfactory receptors are heteromeric ligand-gated cation channels composed of an obligatory receptor subunit, ORco, and one of many variable subunits, ORx, in as yet undefined molar ratios. When expressed alone ex vivo, ORco forms homotetrameric channels gated by ORco-specific ligands acting as channel agonists. Using an insect cell-based system as a functional platform for expressing mosquito odorant receptors ex vivo, we identified small molecules of natural origin acting as specific ORco channel antagonists, orthosteric or allosteric relative to a postulated ORco agonist binding site, which cause severe inhibition of olfactory function in mosquitoes. In the present communication, we have compiled common structural features of such orthosteric antagonists and developed a ligand-based pharmacophore whose properties are deemed necessary for binding to the agonist binding site and causing inhibition of ORco's biological function. In silico screening of an available collection of natural volatile compounds with the pharmacophore resulted in identification of several ORco antagonist hits. Cell-based functional screening of the same compound collection resulted in the identification of several compounds acting as orthosteric and allosteric antagonists of ORco channel function ex vivo and inducing anosmic behaviors to Aedes albopictus mosquitoes in vivo. Comparison of the in silico screening results with those of the functional assays revealed that the pharmacophore predicted correctly 7 out of the 8 confirmed orthosteric antagonists and none of the allosteric ones. Because the pharmacophore screen produced additional hits that did not cause inhibition of the ORco channel function, we also generated a Support Vector Machine (SVM) model based on two descriptors of all pharmacophore hits. Training of the SVM on the ex vivo validated compound collection resulted in the selection of the confirmed orthosteric antagonists with a very low cross-validation out-of-sample misclassification rate. Employment of the combined pharmacophore-SVM platform for in silico screening of a larger collection of olfaction-relevant volatiles produced several new hits. Functional validation of randomly selected hits and rejected compounds from this screen confirmed the power of this virtual screening platform as a convenient tool for accelerating the pace of discovery of novel vector control agents. To the best of our knowledge, this study is the first one that combines a pharmacophore with a SVM model for identification of AgamORco antagonists and specifically orthosteric ones.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545657","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}

{"title":"Molecular counting of myosin force generators in growing filopodia.","authors":"Gillian N Fitz, Matthew J Tyska","doi":"10.1016/j.jbc.2024.107934","DOIUrl":"10.1016/j.jbc.2024.107934","url":null,"abstract":"<p><p>Animal cells build actin-based surface protrusions to enable diverse biological activities, ranging from cell motility to mechanosensation to solute uptake. Long-standing models of protrusion growth suggest that actin filament polymerization provides the primary mechanical force for \"pushing\" the plasma membrane outward at the distal tip. Expanding on these actin-centric models, our recent studies used a chemically inducible system to establish that plasma membrane-bound myosin motors, which are abundant in protrusions and accumulate at the distal tips, can also power robust filopodial growth. How protrusion resident myosins coordinate with actin polymerization to drive elongation remains unclear, in part because the number of force generators and thus, the scale of their mechanical contributions remain undefined. To address this gap, we leveraged the SunTag system to count membrane-bound myosin motors in actively growing filopodia. Using this approach, we found that the number of myosins is log-normally distributed with a mean of 12.0 ± 2.5 motors [GeoMean ± GeoSD] per filopodium. Together with unitary force values and duty ratio estimates derived from biophysical studies for the motor used in these experiments, we calculate that a distal tip population of myosins could generate a time averaged force of ∼tens of pN to elongate filopodia. This range is comparable to the expected force production of actin polymerization in this system, a point that necessitates revision of popular physical models for protrusion growth.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545656","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}

{"title":"Epididymis-specific RNase A family genes regulate fertility and small RNA processing.","authors":"Joshua F Shaffer, Alka Gupta, Geetika Kharkwal, Edgardo E Linares, Andrew D Holmes, Julian R Swartz, Sol Katzman, Upasna Sharma","doi":"10.1016/j.jbc.2024.107933","DOIUrl":"10.1016/j.jbc.2024.107933","url":null,"abstract":"<p><p>Sperm small RNAs are implicated in intergenerational transmission of paternal environmental effects. Small RNAs generated by cleavage of tRNAs, known as tRNA fragments (tRFs) or tRNA-derived RNAs (tDRs or tsRNAs), are an abundant class of RNAs in mature sperm and can be modulated by environmental conditions. The biogenesis of tRFs in the male reproductive tract remains poorly understood. Angiogenin, a member of the Ribonuclease A superfamily (RNase A), cleaves tRNAs to generate tRFs in response to cellular stress. Four paralogs of Angiogenin, namely Rnase9, Rnase10, Rnase11, and Rnase12, are specifically expressed in the epididymis -a long, convoluted tubule where sperm mature and acquire fertility and motility. Here, by generating mice deleted for all four genes (Rnase9-12-/-, termed \"KO\" for Knock Out), we report that these genes regulate fertility and small RNA levels. KO male mice are sterile; KO sperm fertilized oocytes in vitro but failed to efficiently fertilize oocytes in vivo due to an inability of sperm to pass through the utero-tubular junction. Intriguingly, there were decreased levels of fragments of tRNAs (tRFs) and rRNAs (rRNA-derived small RNAs or rsRNAs) in the KO epididymis and epididymal luminal fluid, although RNases 9-12 did not show ribonucleolytic activity in-vitro. Importantly, KO sperm showed a dramatic decrease in the levels of tRFs, demonstrating a role of epididymis-specific Rnase9-12 genes in regulating sperm small RNA composition. Together, our results reveal an unexpected role of four epididymis-specific non-canonical RNase A family genes in regulating fertility and small RNA processing.</p>","PeriodicalId":15140,"journal":{"name":"Journal of Biological Chemistry","volume":null,"pages":null},"PeriodicalIF":4.0,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545654","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}