BACKGROUND: The 'CLB2 cluster' in Saccharomyces cerevisiae consists of approximately 33 genes whose transcription peaks in late G2/early M phase of the cell cycle. Many of these genes are required for execution of the mitotic program and then for cytokinesis. The transcription factor SFF (SWI5 factor) is thought to regulate a program of mitotic transcription in conjunction with the general transcription factor Mcm1p. The identity of SFF has yet to be determined; hence further understanding of the mechanisms that regulate entry to M phase at the transcriptional level requires characterization of SFF at the molecular level. RESULTS: We have purified the biochemical activity corresponding to SFF and identified it as the forkhead transcription factor Fkh2p. Fkh2p assembles into ternary complexes with Mcm1p on both the SWI5 and CLB2 cell-cycle-regulated upstream activating sequence (UAS) elements in vitro, and in an Mcm1 p-dependent manner in vivo. Another closely related forkhead protein, Fkh1p, is also recruited to the CLB2 promoter in vivo. We show that both FKH1 and FKH2 play essential roles in the activation of the CLB2 cluster genes during G2-M and in establishing their transcriptional periodicity. Hence, Fkh1p and Fkhp2 show the properties expected of SFF, both in vitro and in vivo. CONCLUSIONS: Forkhead transcription factors have redundant roles in the control of CLB2 cluster genes during the G2-M period of the cell cycle, in collaboration with Mcm1p.
BACKGROUND: The 'CLB2 cluster' in Saccharomyces cerevisiae consists of approximately 33 genes whose transcription peaks in late G2/early M phase of the cell cycle. Many of these genes are required for execution of the mitotic program and then for cytokinesis. The transcription factor SFF (SWI5 factor) is thought to regulate a program of mitotic transcription in conjunction with the general transcription factor Mcm1p. The identity of SFF has yet to be determined; hence further understanding of the mechanisms that regulate entry to M phase at the transcriptional level requires characterization of SFF at the molecular level. RESULTS: We have purified the biochemical activity corresponding to SFF and identified it as the forkhead transcription factor Fkh2p. Fkh2p assembles into ternary complexes with Mcm1p on both the SWI5 and CLB2 cell-cycle-regulated upstream activating sequence (UAS) elements in vitro, and in an Mcm1 p-dependent manner in vivo. Another closely related forkhead protein, Fkh1p, is also recruited to the CLB2 promoter in vivo. We show that both FKH1 and FKH2 play essential roles in the activation of the CLB2 cluster genes during G2-M and in establishing their transcriptional periodicity. Hence, Fkh1p and Fkhp2 show the properties expected of SFF, both in vitro and in vivo. CONCLUSIONS: Forkhead transcription factors have redundant roles in the control of CLB2 cluster genes during the G2-M period of the cell cycle, in collaboration with Mcm1p.
Authors: Mark Anderson; Szu Shien Ng; Vanessa Marchesi; Fiona H MacIver; Frances E Stevens; Tracy Riddell; David M Glover; Iain M Hagan; Christopher J McInerny Journal: EMBO J Date: 2002-11-01 Impact factor: 11.598
Authors: Christine E Horak; Nicholas M Luscombe; Jiang Qian; Paul Bertone; Stacy Piccirrillo; Mark Gerstein; Michael Snyder Journal: Genes Dev Date: 2002-12-01 Impact factor: 11.361
Authors: John C Herriges; Lan Yi; Elizabeth A Hines; Julie F Harvey; Guoliang Xu; Paul A Gray; Qiufu Ma; Xin Sun Journal: Dev Dyn Date: 2012-07-20 Impact factor: 3.780