- Author:
Feifei WEI
1
;
Han XIAO
;
Zhiping HU
;
Hainan ZHANG
;
Chunyu WANG
;
Heping DAI
;
Jianguang TANG
Author Information
- Publication Type:Journal Article
- MeSH: Ataxin-3; Cytoplasm; genetics; metabolism; Endoplasmic Reticulum; genetics; metabolism; HeLa Cells; Humans; Machado-Joseph Disease; genetics; metabolism; Mitochondria; genetics; metabolism; Nerve Tissue Proteins; genetics; metabolism; Nuclear Proteins; genetics; metabolism; Protein Transport; Repressor Proteins; genetics; metabolism
- From: Chinese Journal of Medical Genetics 2015;32(3):353-357
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo 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.
METHODSTransient transfection was employed to build cell models expressing wild-type 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.
RESULTSNo co-localization 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 co-localization 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.
CONCLUSIONPolyQ-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.