| First Author | Watson RJ | Year | 1993 |
| Journal | Nucleic Acids Res | Volume | 21 |
| Issue | 2 | Pages | 267-72 |
| PubMed ID | 8382794 | Mgi Jnum | J:3741 |
| Mgi Id | MGI:52250 | Doi | 10.1093/nar/21.2.267 |
| Citation | Watson RJ, et al. (1993) Transcription regulation by murine B-myb is distinct from that by c-myb. Nucleic Acids Res 21(2):267-72 |
| abstractText | The transcription regulatory properties of murine B-myb protein were compared to those of c-myb. Whereas c-Myb trans-activated an SV40 early promoter containing multiple copies of an upstream c-Myb DNA-binding site (MBS-1), and similarly the human c-myc promoter, B-Myb was unable to do so. Full-length B-Myb translated in vitro did not bind MBS-1; however, truncation of the B-Myb C-terminus or fusion of the B-Myb DNA-binding domain to the c-Myb C-terminus showed that it was inherently competent to interact with this motif. Further evidence from co-transfection experiments, demonstrating that B-Myb inhibited trans-activation by c-Myb, suggested that failure of B-Myb to trans-activate these promoters did not simply occur through lack of binding to MBS-1. Moreover, using GAL4/B-Myb fusions, it was found that an acidic region of B-Myb, which by comparison to c-Myb was expected to contain a transcription activation domain, actually had no inherent trans-activation activity and indeed appeared to trans-inhibit c-Myb. In contrast to the above findings, both B-Myb and c-Myb were able to weakly trans-activate the DNA polymerase alpha promoter. Results obtained here demonstrate that the activities of B-Myb and c-Myb are clearly distinct and suggest that these related proteins may have different functions in regulation of target gene expression. |
