First Author | Irwin S | Year | 2005 |
Journal | J Cell Sci | Volume | 118 |
Issue | Pt 1 | Pages | 233-42 |
PubMed ID | 15615787 | Mgi Jnum | J:94966 |
Mgi Id | MGI:3522382 | Doi | 10.1242/jcs.01611 |
Citation | Irwin S, et al. (2005) RNA association and nucleocytoplasmic shuttling by ataxin-1. J Cell Sci 118(Pt 1):233-42 |
abstractText | Spinocerebellar ataxia type 1 (SCA1) is a dominant neurodegenerative disease caused by the expression of mutant ataxin-1 containing an expanded polyglutamine tract. Ataxin-1 is a nuclear protein that localizes to punctate inclusions similar to neuronal nuclear inclusions seen in many polyglutamine expansion disease proteins. We demonstrate that ataxin-1 localization to inclusions and inclusion dynamics within the nucleus are RNA and transcription dependent, but not dependent on the polyglutamine tract. Ataxin-1 nuclear inclusions are distinct from other described nuclear bodies but recruit the mRNA export factor, TAP/NXF1, in a manner that is enhanced by cell heat shock. By FRAP protein dynamic studies in live cells, we found that wild-type, but not mutant, ataxin-1 was capable of nuclear export. These results suggest that the normal role of ataxin-1 may be in RNA processing, perhaps nuclear RNA export. Thus, nuclear retention of mutant ataxin-1 may be an important toxic gain of function in SCA1 disease. |