Background:During Enterovirus type 71(EV71)infection,the structural viral protein 1(VP1)activates endoplasmic reticulum(ER)stress associated with peripheral myelin protein 22(PMP22)accumulation and induces autophagy.H...Background:During Enterovirus type 71(EV71)infection,the structural viral protein 1(VP1)activates endoplasmic reticulum(ER)stress associated with peripheral myelin protein 22(PMP22)accumulation and induces autophagy.However,the specific mechanism behind this process remains elusive.Methods:In this research,we used the VP1-overexpressing mouse Schwann cells(SCs)models co-transfected with a PMP22 silencing or Autocrine motility factor receptor(AMFR/gp78)overexpressing vector to explore the regulation of gp78 on PMP22 and its relationship with autophagy and apoptosis.Results:The activity of gp78 could be influenced by EV71-VP1,leading to a decrease in the ubiquitination and degradation of PMP22,resulting in PMP22 accumulation in ER.In VP1-overexpressing mouse SCs,all three ER stress sensors,including pancreatic endoplasmic reticulum kinase(PERK),activating transcription factor 6(ATF6)and inositol-requiring enzyme 1(IRE1)and the related downstream signals(C/EBP-homologous protein(CHOP)and Caspase 12)were activated,as well as the ER-resident chaperone Glucose-regulated protein 78(GRP78).In addition,VP1 upregulated the autophagy marker Microtubule-associated protein 1 light chain 3 beta(LC3B),while PMP22 silencing or gp78 overexpression reversed the phenomenon.Meanwhile,PMP22 silencing or gp78 overexpression increased proliferation of EV71-VP1-transfected mouse SCs.Conclusion:Gp78 could regulate PMP22 accumulation through ubiquitination degradation and cause ER stress and autophagy in EV71-VP1-overexpressing mouse SCs.Therefore,the gp78/PMP22/ER stress axis might emerge as a promising therapeutic target for myelin and neuronal damage induced by EV71 infection.展开更多
Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure pal...Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure palsies (HNPP). HNPP is caused by a heterozygous deletion of PMP22 gene. PMP22 deficiency disrupts myelin junctions (such as tight junction and adherens junctions), leading to abnormally increased myelin permeability that explains the nerve susceptibility to injury. This finding should motivate investigators to identify additional genetic factors contribut- ing to nerve vulnerability of injury.展开更多
基金The study was supported by Guangdong Natural Science Foundation(Grant Numbers 2020A1515010014,2022A1515012411)Science and Technology Key Project for People’s Livelihood of Guangzhou,China(Grant Number 202206010060)+1 种基金Guangzhou Science and Technology Bureau Basic Research Project(SL2024A03J01288)Innovative Project of Children’s Research Institute,Guangzhou Women and Children’s Medical Center,China(Grant Numbers Pre-NSFC-2019-002,NKE PRE-2019-015).
文摘Background:During Enterovirus type 71(EV71)infection,the structural viral protein 1(VP1)activates endoplasmic reticulum(ER)stress associated with peripheral myelin protein 22(PMP22)accumulation and induces autophagy.However,the specific mechanism behind this process remains elusive.Methods:In this research,we used the VP1-overexpressing mouse Schwann cells(SCs)models co-transfected with a PMP22 silencing or Autocrine motility factor receptor(AMFR/gp78)overexpressing vector to explore the regulation of gp78 on PMP22 and its relationship with autophagy and apoptosis.Results:The activity of gp78 could be influenced by EV71-VP1,leading to a decrease in the ubiquitination and degradation of PMP22,resulting in PMP22 accumulation in ER.In VP1-overexpressing mouse SCs,all three ER stress sensors,including pancreatic endoplasmic reticulum kinase(PERK),activating transcription factor 6(ATF6)and inositol-requiring enzyme 1(IRE1)and the related downstream signals(C/EBP-homologous protein(CHOP)and Caspase 12)were activated,as well as the ER-resident chaperone Glucose-regulated protein 78(GRP78).In addition,VP1 upregulated the autophagy marker Microtubule-associated protein 1 light chain 3 beta(LC3B),while PMP22 silencing or gp78 overexpression reversed the phenomenon.Meanwhile,PMP22 silencing or gp78 overexpression increased proliferation of EV71-VP1-transfected mouse SCs.Conclusion:Gp78 could regulate PMP22 accumulation through ubiquitination degradation and cause ER stress and autophagy in EV71-VP1-overexpressing mouse SCs.Therefore,the gp78/PMP22/ER stress axis might emerge as a promising therapeutic target for myelin and neuronal damage induced by EV71 infection.
文摘周围髓鞘蛋白22基因(peripheral myelin protein-22,PMP22)相关性周围神经病是一组以PMP22基因突变导致的遗传性周围神经病,不同的突变类型是导致不同的临床表型的关键,大致可以分为五类:PMP22片段重复突变导致腓骨肌萎缩症1A型(Charcot-Marie-Tooth type-1A,CMT1A),PMP22缺失突变所致遗传性压迫易感性神经病(hereditary neuropathy with liability to pressure palsies,HNPP),PMP22基因点突变可引起CMT1E以及Dejerine-Sottas综合征(DSS)、Roussy-Levy综合征(RLS)等。本文就PMP22基因相关性周围神经病的临床及遗传学特点做一综述。
基金supported by grants from NINDS R01NS066927Department of Veterans Affairs R&D funds
文摘Genetic factors may be learnt from families with gene mutations that render nerve-injury sus- ceptibility even to ordinary physical activities. A typical example is hereditary neuropathy with liability to pressure palsies (HNPP). HNPP is caused by a heterozygous deletion of PMP22 gene. PMP22 deficiency disrupts myelin junctions (such as tight junction and adherens junctions), leading to abnormally increased myelin permeability that explains the nerve susceptibility to injury. This finding should motivate investigators to identify additional genetic factors contribut- ing to nerve vulnerability of injury.