中华医学遗传学杂志
中華醫學遺傳學雜誌
중화의학유전학잡지
CHINESE JOURNAL OF MEDICAL GENETICS
2015年
3期
353-357
,共5页
魏飞飞%肖涵%胡治平%张海南%王春喻%戴和平%汤建光
魏飛飛%肖涵%鬍治平%張海南%王春喻%戴和平%湯建光
위비비%초함%호치평%장해남%왕춘유%대화평%탕건광
脊髓小脑共济失调Ⅲ型/马查多-约瑟夫病%多聚谷氨酰胺%线粒体%高尔基体%内质网
脊髓小腦共濟失調Ⅲ型/馬查多-約瑟伕病%多聚穀氨酰胺%線粒體%高爾基體%內質網
척수소뇌공제실조Ⅲ형/마사다-약슬부병%다취곡안선알%선립체%고이기체%내질망
Spinocerebellar ataxia type 3/Machado-Joseph disease%Polyglutamine%Mitochondrion%Golgi apparatus%Endoplasmic reticulum
目的 探讨ataxin-3蛋白的亚细胞定位及其多聚谷氨酰胺(polyglutamine,polyQ)扩展突变对线粒体、高尔基体和内质网形态的影响.方法 采用瞬时转染法构建表达野生型和突变型ataxin-3蛋白的细胞模型,用间接免疫荧光法识别细胞器膜的标记蛋白,在激光共聚焦显微镜下观察.结果 ataxin-3与TOM20无共定位,但突变组线粒体碎裂细胞百分比增加(P<0.05);ataxin-3与GM130无共定位且突变组无高尔基体碎裂;ataxin-3与calnexin部分共定位,突变组重叠信号较多且大多位于聚集体所在处.结论 polyQ扩展型ataxin-3蛋白可能间接损害线粒体完整性但并不影响高尔基体的结构和功能,而内质网可能是扩展型ataxin-3蛋白在细胞核外发挥毒性作用的场所.
目的 探討ataxin-3蛋白的亞細胞定位及其多聚穀氨酰胺(polyglutamine,polyQ)擴展突變對線粒體、高爾基體和內質網形態的影響.方法 採用瞬時轉染法構建錶達野生型和突變型ataxin-3蛋白的細胞模型,用間接免疫熒光法識彆細胞器膜的標記蛋白,在激光共聚焦顯微鏡下觀察.結果 ataxin-3與TOM20無共定位,但突變組線粒體碎裂細胞百分比增加(P<0.05);ataxin-3與GM130無共定位且突變組無高爾基體碎裂;ataxin-3與calnexin部分共定位,突變組重疊信號較多且大多位于聚集體所在處.結論 polyQ擴展型ataxin-3蛋白可能間接損害線粒體完整性但併不影響高爾基體的結構和功能,而內質網可能是擴展型ataxin-3蛋白在細胞覈外髮揮毒性作用的場所.
목적 탐토ataxin-3단백적아세포정위급기다취곡안선알(polyglutamine,polyQ)확전돌변대선립체、고이기체화내질망형태적영향.방법 채용순시전염법구건표체야생형화돌변형ataxin-3단백적세포모형,용간접면역형광법식별세포기막적표기단백,재격광공취초현미경하관찰.결과 ataxin-3여TOM20무공정위,단돌변조선립체쇄렬세포백분비증가(P<0.05);ataxin-3여GM130무공정위차돌변조무고이기체쇄렬;ataxin-3여calnexin부분공정위,돌변조중첩신호교다차대다위우취집체소재처.결론 polyQ확전형ataxin-3단백가능간접손해선립체완정성단병불영향고이기체적결구화공능,이내질망가능시확전형ataxin-3단백재세포핵외발휘독성작용적장소.
Objective To explore the subcellular localization of ataxin-3 and the effect of polyglutamine (polyQ) expansion mutation on the morphology of mitochondrion,golgi apparatus and endoplasmic reticulum.Methods Transient transfeetion was employed to build cell models expressing wildtype or mutant ataxin-3 proteins.Indirect immunofluorescence was applied to identify markers of organelle membrane.The results were observed under a laser scanning confocal microscope.Results No colocalization was observed for ataxin-3 protein and mitochondrial marker TOM20,but the percentage of cells with mitochondrial fragmentation has increased in cells expressing mutant ataxin-3 (P< 0.05).No colocalization was observed for ataxin-3 protein and golgi marker GM130,and mutant ataxin-3 did not cause golgi fragmentation.Wide type and polyQ-expanded ataxin-3 both showed partial co-localization with ER marker calnexin.The latter showed more overlap with calnexin,and the overlapping signals were mostly located in the places where aggregates were situated.Conclusion PolyQ-expanded ataxin-3 protein may indirectly affect the integrity of mitochondria,but may cause no effect on the structure and functions of golgi apparatus.Endoplasmic reticulum may be another place where extended ataxin-3 protein can induce cytotoxicity in addition to the nucleus.