Characterization and cell cycle-regulated expression of mouse B-myb.
We have isolated a full-length mouse B-myb cDNA clone and used this to examine cell cycle-regulated expression of this gene. Mouse B-Myb was predicted to comprise 704 amino acids and to be 84% homologous with human B-Myb. There were three regions of extensive amino acid homology which may indicate functional domains: the first corresponded to the c-Myb DNA-binding domain, while the second had no counterpart in c-Myb but was instead homologous to a short segment of the related A-myb protein. The third region of homology is partially conserved in both c-Myb and A-Myb and may correspond to the c-Myb negative regulatory domain. Stimulation of quiescent 3T3 fibroblasts with serum was found to result in induction of B-myb expression in late G1 and to lead to high levels of gene transcripts that persisted through S phase. Similarly, maximum B-myb mRNA levels were reached in G2/M synchronized cells prior to entry into S phase. These results are consistent with a role in G1/S transition as has been suggested for c-myb.
Lam
E W
EW
Ludwig Institute for Cancer Research, St Mary's Hospital Medical School, London, UK.
Robinson
C
C
Watson
R J
RJ
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle; D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins / Q000235:genetics*; D005786:Gene Expression Regulation; D006801:Humans; D051379:Mice; D008969:Molecular Sequence Data; D011519:Proto-Oncogenes; D012333:RNA, Messenger / Q000032:analysis; D015534:Trans-Activators; D014157:Transcription Factors / Q000235:genetics*
D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; C064352:MYBL2 protein, human; C499306:Mybl2 protein, mouse; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors