First Author | Zhong S | Year | 2007 |
Journal | Mol Cell Biol | Volume | 27 |
Issue | 1 | Pages | 54-64 |
PubMed ID | 17074809 | Mgi Jnum | J:117728 |
Mgi Id | MGI:3697300 | Doi | 10.1128/MCB.01365-06 |
Citation | Zhong S, et al. (2007) TBP is differentially regulated by c-Jun N-terminal kinase 1 (JNK1) and JNK2 through Elk-1, controlling c-Jun expression and cell proliferation. Mol Cell Biol 27(1):54-64 |
abstractText | Emerging evidence supports the idea that the c-Jun N-terminal kinases (JNKs) possess overlapping but distinct functions. The potential roles of the ubiquitously expressed JNK1 and JNK2 in regulating expression of the central transcription initiation factor, TATA-binding protein (TBP), were examined. Relative to wild-type fibroblasts, TBP was decreased in Jnk1(-/-) cells and increased in Jnk2(-/-) cells. Similarly, reduction of JNK1 in human hepatoma cells decreased TBP expression, whereas reduction of JNK2 enhanced it. JNK-mediated regulation of TBP expression occurs at the transcriptional level through their ability to target Elk-1, which directly regulates the TBP promoter in response to epidermal growth factor stimulation. JNK1 increases, whereas JNK2 decreases, the phosphorylation state of Elk-1, which differentially affects Elk-1 occupancy at a defined site within the TBP promoter. These JNK-mediated alterations in TBP expression, alone, serve to regulate c-Jun expression and fibroblast proliferation rates. These studies uncovered several new molecular events that distinguish the functions of JNK1 and JNK2 that are critical for their regulation of cellular proliferation. |