| RRC ID |
2386
|
| 著者 |
Ishihara K, Yamagishi N, Saito Y, Adachi H, Kobayashi Y, Sobue G, Ohtsuka K, Hatayama T.
|
| タイトル |
Hsp105alpha suppresses the aggregation of truncated androgen receptor with expanded CAG repeats and cell toxicity.
|
| ジャーナル |
J Biol Chem
|
| Abstract |
Spinal and bulbar muscular atrophy (SBMA) is a neurodegenerative disorder caused by the expansion of a polyglutamine tract in the androgen receptor (AR). The N-terminal fragment of AR containing the expanded polyglutamine tract aggregates in cytoplasm and/or in nucleus and induces cell death. Some chaperones such as Hsp40 and Hsp70 have been identified as important regulators of polyglutamine aggregation and/or cell death in neuronal cells. Recently, Hsp105alpha, expressed at especially high levels in mammalian brain, has been shown to suppress apoptosis in neuronal cells and prevent the aggregation of protein caused by heat shock in vitro. However, its role in polyglutamine-mediated cell death and toxicity has not been studied. In the present study, we examined the effects of Hsp105alpha on the aggregation and cell toxicity caused by expansion of the polyglutamine tract using a cellular model of SBMA. The transient expression of truncated ARs (tARs) containing an expanded polyglutamine tract caused aggregates to form in COS-7 and SK-N-SH cells and concomitantly apoptosis in the cells with the nuclear aggregates. When Hsp105alpha was overexpressed with tAR97 in the cells, Hsp105alpha was colocalized to aggregates of tAR97, and the aggregation and cell toxicity caused by expansion of the polyglutamine tract were markedly reduced. Both beta-sheet and alpha-helix domains, but not the ATPase domain, of Hsp105alpha were necessary to suppress the formation of aggregates in vivo and in vitro. Furthermore, Hsp105alpha was found to localize in nuclear inclusions formed by ARs containing an expanded polyglutamine tract in tissues of patients and transgenic mice with SBMA. These findings suggest that overexpression of Hsp105alpha suppresses cell death caused by expansion of the polyglutamine tract without chaperone activity, and the enhanced expression of the essential domains of Hsp105alpha in brain may provide an effective therapeutic approach for CAG repeat diseases.
|
| 巻・号 |
278(27)
|
| ページ |
25143-50
|
| 公開日 |
2003-7-4
|
| DOI |
10.1074/jbc.M302975200
|
| PII |
S0021-9258(20)86979-8
|
| PMID |
12714591
|
| MeSH |
Animals
COS Cells
Cell Death
Cell Line
Gene Expression Regulation
HSP110 Heat-Shock Proteins
HSP70 Heat-Shock Proteins / genetics
HSP70 Heat-Shock Proteins / metabolism*
Humans
Mice
Mice, Transgenic
Receptors, Androgen / genetics
Receptors, Androgen / metabolism*
Recombinant Proteins
Trinucleotide Repeat Expansion
|
| IF |
4.238
|
| 引用数 |
60
|
|
WOS 分野
|
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
| リソース情報 |
| 実験動物マウス |
RBRC00344
RBRC00373 |
| ヒト・動物細胞 |
COS-7(RCB0539)
SK-N-SH(RCB0426) |
