Positive and Negative Regulation of the Cardiovascular Transcription Factor KLF5 by p300 and the Oncogenic Regulator SET through Interaction and Acetylation on the DNA-Binding Domain

Abstract

Here we show a novel pathway of transcriptional regulation of a DNA-binding transcription factor by coupled interaction and modification (e.g., acetylation) through the DNA-binding domain (DBD). The oncogenic regulator SET was isolated by affinity purification of factors interacting with the DBD of the cardiovascular transcription factor KLF5. SET negatively regulated KLF5 DNA binding, transactivation, and cell-proliferative activities. Down-regulation of the negative regulator SET was seen in response to KLF5-mediated gene activation. The coactivator/acetylase p300, on the other hand, interacted with and acetylated KLF5 DBD, and activated its transcription. Interestingly, SET inhibited KLF5 acetylation, and a nonacetylated mutant of KLF5 showed reduced transcriptional activation and cell growth complementary to the actions of SET. These findings suggest a new pathway for regulation of a DNA-binding transcription factor on the DBD through interaction and coupled acetylation by two opposing regulatory factors of a coactivator/acetylase and a negative cofactor harboring activity to inhibit acetylation.

ACKNOWLEDGMENTS

We thank K. Nagata, Y. Nakatani, V. Ogryzko, and C. Teng for constructs and reagents. We thank Takayoshi Matsumura, Kana Sasaki, Nanae Kada, and Yoshiko Munemasa for assistance.

This study was supported by grants from the Ministry of Education, Culture, Sports, Science, and Technology; New Energy and Industrial Technology Development Organization; Ministry of Health, Labor, and Welfare; Japan Science and Technology Corporation; Sankyo Life Science Foundation; Takeda Medical Research Foundation; Japan Heart Foundation (Zeria grant); and the Applied Enzyme Association.

S. Miyamoto, T. Suzuki, S. Muto, and K. Aizawa contributed equally to this work.