Related Experiment Video
Updated: Aug 9, 2026

Analysis of Cell Cycle Position in Mammalian Cells
Published on: January 21, 2012
B-myb promotes S phase and is a downstream target of the negative regulator p107 in human cells
1Thomas Jefferson University, Department of Microbiology and Immunology and Jefferson Cancer Institute, Philadelphia, Pennsylvania 19107, USA.
Abstract:
The retinoblastoma protein family has been implicated in growth control and modulation of the activity of genes involved in cell proliferation, such as B-myb. Recent evidence indicates that the product of the B-myb gene is necessary for the growth and survival of several human and murine cell lines. Upon overexpression, B-myb induces deregulated cell growth of certain cell lines. Here we show that B-myb overexpression is able to induce DNA synthesis in p107 growth-arrested human osteosarcoma cells (SAOS2). p107 might exert its growth-suppressive activity by regulating B-myb gene transcription. Indeed, p107 down-modulated B-myb promoter activity and drastically decreased E2F-mediated transactivation. Finally, B-myb was able to stimulate DNA synthesis of both stably and transiently transfected human glioblastoma cells (T98G). Altogether, these data provide definitive evidence that the human B-myb protein is involved in growth control of human cells, and that p107 has a significant role in regulating B-myb gene activity.
Related Concept Videos
Positive Regulator Molecules
Negative Regulator Molecules
Positive Regulator Molecules
Inhibition of Cdk Activity
Abnormal Proliferation
Molecular Factors Affecting Cell Division
Several proteins function as internal regulators to ensure each cell cycle stage is completed faithfully before proceeding to the next. Regulator molecules may act directly or influence the activity or production of other...

