Regulation of HSF1-responsive gene expression by N-terminal truncated form of p73alpha |
| |
Authors: | Tanaka Yasuharu Kameoka Masanori Itaya Asako Ota Katsuya Yoshihara Koichiro |
| |
Institution: | Department of Biochemistry, Nara Medical University, Shijo-Cho 840, Kashihara, Nara 634-8521, Japan. ytanaka@naramed-u.ac.jp |
| |
Abstract: | DNp73 is a transactivation domain (TAD)-truncated form of p73. The ability of DNp73alpha to regulate gene expression was examined using reporter assays with luciferase gene constructs. Among various promoter-regulated reporter genes tested, heat shock factor (HSF)-responsive gene expression was selectively activated by DNp73alpha, but not by other p73-isoforms with TAD and DNp73beta. Deletion of TAD endowed p73alpha with the ability to activate HSF-responsive gene expression, but deletion of N-terminal proline-rich domain (PRD) rendered both DNp73alpha and the TAD-deleted p73alpha inactive. Considering the inability of DNp73beta, which is the C-terminus-truncated form of DNp73alpha, to function, these results indicate that both the PRD and C-terminus are necessary for DNp73alpha to be able to activate the HSF-dependent gene expression. In addition to the reporter gene expression, both DNp73alpha and TAD-deleted p73alpha activated the expression of an endogenous gene, hsp70, corresponding with an increase in the active form of HSF1. Taken together, these results demonstrate that TAD-truncated p73alpha can activate HSF-dependent gene expression via induction of active HSF1. |
| |
Keywords: | p73 TAp73 DNp73 ΔNp73 Heat shock factor Heat shock protein HSF Hsp p53 |
本文献已被 ScienceDirect PubMed 等数据库收录! |
|