该文报道2例白质消融性白质脑病(leukoencephalopathy with vanishing white matter,VWM)。患者1,女,2岁3个月,临床以反复感染后运动能力倒退为主要表现,病情进展迅速,发病6个月时有癫痫发作,此后患者不能独立行走,吞咽困难;基因检测发...该文报道2例白质消融性白质脑病(leukoencephalopathy with vanishing white matter,VWM)。患者1,女,2岁3个月,临床以反复感染后运动能力倒退为主要表现,病情进展迅速,发病6个月时有癫痫发作,此后患者不能独立行走,吞咽困难;基因检测发现,该患者的EIF2B4基因存在7号外显子c.594C>G (p.I98M)和11号外显子c.1177T>A(p.Y393N)的复合杂合突变,其中前者来自父亲、后者来自母亲,且2个位点均是未曾报道的新错义突变。患者2,女,41岁,临床以进行性双下肢无力及记忆力减退为主要表现;基因检测发现,该患者的EIF2B3基因存在2号外显子c.130G>A(p.G44K)和8号外显子c.934C>G (p.R312G)的复合杂合突变,其中后者位点的突变已有报道,但此突变类型为首次报告,且该患者是中国报道的第2例成人型VWM。2例患者的头颅磁共振成像均表现为弥漫对称性脑白质病变;其中,患者1白质稀薄更突出,患者2主要表现为白质萎缩、脑室扩大。发病年龄是VWM严重程度的临床预测因子,起病越早则病情进展越迅速。应激是发病及神经恶化的诱因,目前VWM尚无有效的治疗方法。该文对上述2个病例进行报道,旨在提升临床医师对疾病的认识及早期诊断的能力,以期延缓疾病的进展、延长患者的生存期。展开更多
自质消融性自质脑病（leukoencephalopathy with vanishing white matter，VWM）又称儿童共济失调伴中枢神经系统髓鞘化不良（childhood ataxia with central nervous system hypomyelination，CACH，OMIM306896），是一种常染色体隐性...自质消融性自质脑病（leukoencephalopathy with vanishing white matter，VWM）又称儿童共济失调伴中枢神经系统髓鞘化不良（childhood ataxia with central nervous system hypomyelination，CACH，OMIM306896），是一种常染色体隐性遗传的向质脑病，是儿童遗传性自质脑病中常见的类型之一，其患病率尚缺乏统计。展开更多
Eukaryotic translation initiation factor eIF2B,the guanine nucleotide exchange factor(GEF)for eIF2,catalyzes conversion of eIF2·GDP to eIF2·GTP.The eIF2B is composed of five subunits,α,β,γ,δandε,within ...Eukaryotic translation initiation factor eIF2B,the guanine nucleotide exchange factor(GEF)for eIF2,catalyzes conversion of eIF2·GDP to eIF2·GTP.The eIF2B is composed of five subunits,α,β,γ,δandε,within which theεsubunit is responsible for catalyzing the guanine exchange reaction.Here we present the crystal structure of the C-terminal domain of human eIF2Bε(eIF2Bε-CTD)at 2.0-Åresolution.The structure resembles a HEAT motif and three charge-rich areas on its surface can be identified.When compared to yeast eIF2Bε-CTD,one area involves highly conserved AA boxes while the other two are only partially conserved.In addition,the previously reported mutations in human eIF2Bε-CTD,which are related to the loss of the GEF activity and human VWM disease,have been discussed.Based on the structure,most of such mutations tend to destabilize the HEAT motif.展开更多
文摘该文报道2例白质消融性白质脑病(leukoencephalopathy with vanishing white matter,VWM)。患者1,女,2岁3个月,临床以反复感染后运动能力倒退为主要表现,病情进展迅速,发病6个月时有癫痫发作,此后患者不能独立行走,吞咽困难;基因检测发现,该患者的EIF2B4基因存在7号外显子c.594C>G (p.I98M)和11号外显子c.1177T>A(p.Y393N)的复合杂合突变,其中前者来自父亲、后者来自母亲,且2个位点均是未曾报道的新错义突变。患者2,女,41岁,临床以进行性双下肢无力及记忆力减退为主要表现;基因检测发现,该患者的EIF2B3基因存在2号外显子c.130G>A(p.G44K)和8号外显子c.934C>G (p.R312G)的复合杂合突变,其中后者位点的突变已有报道,但此突变类型为首次报告,且该患者是中国报道的第2例成人型VWM。2例患者的头颅磁共振成像均表现为弥漫对称性脑白质病变;其中,患者1白质稀薄更突出,患者2主要表现为白质萎缩、脑室扩大。发病年龄是VWM严重程度的临床预测因子,起病越早则病情进展越迅速。应激是发病及神经恶化的诱因,目前VWM尚无有效的治疗方法。该文对上述2个病例进行报道,旨在提升临床医师对疾病的认识及早期诊断的能力,以期延缓疾病的进展、延长患者的生存期。
文摘自质消融性自质脑病（leukoencephalopathy with vanishing white matter，VWM）又称儿童共济失调伴中枢神经系统髓鞘化不良（childhood ataxia with central nervous system hypomyelination，CACH，OMIM306896），是一种常染色体隐性遗传的向质脑病，是儿童遗传性自质脑病中常见的类型之一，其患病率尚缺乏统计。
基金This work was supported by the National Programs for High Technology Research and Development Program(863 Program)(Grant No.2006AA02A316)the National Basic Research Program(973 Program)(Grant Nos.2004CB520801,2006CB910903,2007CB914304,2009CB825501 and 2010CB912301)+1 种基金the Ministry of Science and Technology,National Natural Science Foundation of China(Grant Nos.30721003 and 30870484)the Chinese Academy of Sciences(Grant No.KSCX2-YW-R61).
文摘Eukaryotic translation initiation factor eIF2B,the guanine nucleotide exchange factor(GEF)for eIF2,catalyzes conversion of eIF2·GDP to eIF2·GTP.The eIF2B is composed of five subunits,α,β,γ,δandε,within which theεsubunit is responsible for catalyzing the guanine exchange reaction.Here we present the crystal structure of the C-terminal domain of human eIF2Bε(eIF2Bε-CTD)at 2.0-Åresolution.The structure resembles a HEAT motif and three charge-rich areas on its surface can be identified.When compared to yeast eIF2Bε-CTD,one area involves highly conserved AA boxes while the other two are only partially conserved.In addition,the previously reported mutations in human eIF2Bε-CTD,which are related to the loss of the GEF activity and human VWM disease,have been discussed.Based on the structure,most of such mutations tend to destabilize the HEAT motif.
