Viruses often manipulate ubiquitination pathways to facilitate their replication and pathogenesis.CUL2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase,is bound by SARS-CoV-2 ORF10 to increase its E3 l...Viruses often manipulate ubiquitination pathways to facilitate their replication and pathogenesis.CUL2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase,is bound by SARS-CoV-2 ORF10 to increase its E3 ligase activity,leading to degradation of IFT46,a protein component of the intraflagellar transport(IFT)complex B.This results in dysfunctional cilia,which explains certain symptoms that are specific to COVID-19.However,the precise molecular mechanism of how ORF10 recognizes CUL2ZYG11B remains unknown.Here,we determined the crystal structure of CUL2ZYG11B complexed with the N-terminal extension(NTE)of SARS-CoV-2 ORF10(2.9 A°).The structure reveals that the ORF10 N-terminal heptapeptide(NTH)mimics the Gly/N-degron to bind CUL2ZYG11B.Mutagenesis studies identified key residues within ORF10 that are key players in its interaction with CUL2ZYG11B both in ITC assay and in vivo cells.In addition,we prove that enhancement of CUL2ZYG11B activity for IFT46 degradation by which ORF10-mediated correlates with the binding affinity between ORF10 and CUL2ZYG11B.Finally,we used a Global Protein Stability system to show that the NTH of ORF10 mimics the Gly/N-degron motif,thereby binding competitively to CUL2ZYG11B and inhibiting the degradation of target substrates bearing the Gly/N-degron motif.Overall,this study sheds light on how SARS-CoV-2 ORF10 exploits the ubiquitination machinery for proteasomal degradation,and offers valuable insights for optimizing PROTAC-based drug design based on NTH CUL2ZYG11B interaction,while pinpointing a promising target for the development of treatments for COVID-19.展开更多
The global coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has caused severe morbidity and mortality in humans.It is urgent to understand the function of...The global coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has caused severe morbidity and mortality in humans.It is urgent to understand the function of viral genes.However,the function of open reading frame 10(ORF10),which is uniquely expressed by SARS-CoV-2,remains unclear.In this study,we showed that overexpression of ORF10 markedly suppressed the expression of type I interferon(IFN-I)genes and IFN-stimulated genes.Then,mitochondrial antiviral signaling protein(MAVS)was identified as the target via which ORF10 suppresses the IFN-I signaling pathway,and MAVS was found to be degraded through the ORF10-induced autophagy pathway.Furthermore,overexpression of ORF10 promoted the accumulation of LC3 in mitochondria and induced mitophagy.Mechanistically,ORF10 was translocated to mitochondria by interacting with the mitophagy receptor Nip3-like protein X(NIX)and induced mitophagy through its interaction with both NIX and LC3B.Moreover,knockdown of NIX expression blocked mitophagy activation,MAVS degradation,and IFN-I signaling pathway inhibition by ORF10.Consistent with our observations,in the context of SARS-CoV-2 infection,ORF10 inhibited MAVS expression and facilitated viral replication.In brief,our results reveal a novel mechanism by which SARS-CoV-2 inhibits the innate immune response;that is,ORF10 induces mitophagy-mediated MAVS degradation by binding to NIX.展开更多
The authors describe siblings with progressive external ophthalmoplegia (PEO) due to a novel heterozygous A to G transition at nucleotide 955 of C10Orf2 (Twinkle). The mutation was not identified in parents’ blood, h...The authors describe siblings with progressive external ophthalmoplegia (PEO) due to a novel heterozygous A to G transition at nucleotide 955 of C10Orf2 (Twinkle). The mutation was not identified in parents’ blood, hair follicles, buccal mucosa, or urinary epithelium, indicating germ line mosaicism. One sibling presented with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (SANDO), a phenotype previously associated with the POLG1 gene, highlighting the clinical overlap in autosomal PEO.展开更多
基金the following staff members and grant support.BL19U1 beamline of the National Facility for Protein Science in Shanghai(NFPS),BL17U1 beamline,and BL10U2 beamline at the Shanghai Synchrotron Radiation Facility.We thank the staff of PX III beamline at the Swiss Light Source,PaulScherrer Institute(Villigen Switzerland)for assistance in data collection.We thank the staffs from the Core Facility of National Institute of Pathogen Biology,Chinese Academy of Medical Sciences.This work was supported by National Key Research and Development Program of China(2023YFC2307803)Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences(2022-I2M-1-021,China)+2 种基金the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2023-PT310-04,China)National Natural Science Foundation of China(82341095,82261160398,82072291,82272308)the Fundamental Research Funds for the Central Universities(3332021092,China).
文摘Viruses often manipulate ubiquitination pathways to facilitate their replication and pathogenesis.CUL2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase,is bound by SARS-CoV-2 ORF10 to increase its E3 ligase activity,leading to degradation of IFT46,a protein component of the intraflagellar transport(IFT)complex B.This results in dysfunctional cilia,which explains certain symptoms that are specific to COVID-19.However,the precise molecular mechanism of how ORF10 recognizes CUL2ZYG11B remains unknown.Here,we determined the crystal structure of CUL2ZYG11B complexed with the N-terminal extension(NTE)of SARS-CoV-2 ORF10(2.9 A°).The structure reveals that the ORF10 N-terminal heptapeptide(NTH)mimics the Gly/N-degron to bind CUL2ZYG11B.Mutagenesis studies identified key residues within ORF10 that are key players in its interaction with CUL2ZYG11B both in ITC assay and in vivo cells.In addition,we prove that enhancement of CUL2ZYG11B activity for IFT46 degradation by which ORF10-mediated correlates with the binding affinity between ORF10 and CUL2ZYG11B.Finally,we used a Global Protein Stability system to show that the NTH of ORF10 mimics the Gly/N-degron motif,thereby binding competitively to CUL2ZYG11B and inhibiting the degradation of target substrates bearing the Gly/N-degron motif.Overall,this study sheds light on how SARS-CoV-2 ORF10 exploits the ubiquitination machinery for proteasomal degradation,and offers valuable insights for optimizing PROTAC-based drug design based on NTH CUL2ZYG11B interaction,while pinpointing a promising target for the development of treatments for COVID-19.
基金This work was partially supported by grants from the National Natural Science Fund of China(31872490,31972665,and 32072834)Taishan Scholar and Distinguished Experts(to H.H.).
文摘The global coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has caused severe morbidity and mortality in humans.It is urgent to understand the function of viral genes.However,the function of open reading frame 10(ORF10),which is uniquely expressed by SARS-CoV-2,remains unclear.In this study,we showed that overexpression of ORF10 markedly suppressed the expression of type I interferon(IFN-I)genes and IFN-stimulated genes.Then,mitochondrial antiviral signaling protein(MAVS)was identified as the target via which ORF10 suppresses the IFN-I signaling pathway,and MAVS was found to be degraded through the ORF10-induced autophagy pathway.Furthermore,overexpression of ORF10 promoted the accumulation of LC3 in mitochondria and induced mitophagy.Mechanistically,ORF10 was translocated to mitochondria by interacting with the mitophagy receptor Nip3-like protein X(NIX)and induced mitophagy through its interaction with both NIX and LC3B.Moreover,knockdown of NIX expression blocked mitophagy activation,MAVS degradation,and IFN-I signaling pathway inhibition by ORF10.Consistent with our observations,in the context of SARS-CoV-2 infection,ORF10 inhibited MAVS expression and facilitated viral replication.In brief,our results reveal a novel mechanism by which SARS-CoV-2 inhibits the innate immune response;that is,ORF10 induces mitophagy-mediated MAVS degradation by binding to NIX.
文摘The authors describe siblings with progressive external ophthalmoplegia (PEO) due to a novel heterozygous A to G transition at nucleotide 955 of C10Orf2 (Twinkle). The mutation was not identified in parents’ blood, hair follicles, buccal mucosa, or urinary epithelium, indicating germ line mosaicism. One sibling presented with sensory ataxic neuropathy, dysarthria, and ophthalmoparesis (SANDO), a phenotype previously associated with the POLG1 gene, highlighting the clinical overlap in autosomal PEO.
