Regulation of the cell cycle by B-Myb

Blood Cells Mol Dis. Mar-Apr 2001;27(2):416-21. doi: 10.1006/bcmd.2001.0399.


B-Myb is a cell-cycle-regulated member of the Myb transcription factor and, like c-Myb, has been implicated in regulation of hematopoietic cell proliferation and differentiation. In this study we have examined the mechanisms by which B-Myb regulates the cell cycle. We found that the ability of B-Myb both to promote Saos-2 cells into the S phase of the cell cycle and to overcome G1 arrest mediated by overexpression of the retinoblastoma-related p107 protein was correlated with the capacity of B-Myb to form an in vivo complex with p107, but was independent of its transactivation function. Further experiments using a B-Myb dominant-negative protein suggested that transcriptional activation of genes regulated through Myb DNA-binding sequences was required for cell proliferation. Our experiments suggest, therefore, that B-Myb influences cell cycle progression at two distinct levels: by inhibiting p107 and by inducing transcription of specific target genes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Cycle / genetics*
  • Cell Cycle Proteins*
  • DNA-Binding Proteins / genetics*
  • Gene Expression Regulation
  • Humans
  • Trans-Activators / genetics*
  • Transfection
  • Tumor Cells, Cultured


  • Cell Cycle Proteins
  • DNA-Binding Proteins
  • MYBL2 protein, human
  • Trans-Activators