TY - JOUR
T1 - The molecular and functional characterization of E2F-5 transcription factor
AU - Vaishnav, Yashwantrai N.
AU - Vaishnav, Mahima Y.
AU - Pant, Vinod
N1 - Funding Information:
We thank Ed Harlow for providing E2F4CAT and pCMV-DP-1; Joseph Nevins for pHB44-DP-124-410 and pGAD10-E2F-1 wt; G. Nal-lur and H. Vasavada for G5EC, pSG424, AASV-VP16, and Gal4-VP16; V. Kumar for pSGI vector; and N. Jayasuryan for help in raising antibodies. We also thank S. Jameel, S. Sopori, and S. Muk-herjee for critical reading of the manuscript. Technical assistance by R. Verma and S. Sehrawat and cell culture maintenance by R. Kumar are gratefully acknowledged. This work was supported initially by Universitywide AIDS Research Program (UARP) Grant R92-SD-137 and a scholar award from the American Foundation for AIDS Research (AmFAR) to Y.N.V. and subsequently by internal funds from the ICGEB.
PY - 1998/1/26
Y1 - 1998/1/26
N2 - The E2F activity plays a critical role in the control of cell cycle and action of tumor suppressor proteins and is also a target of the transforming proteins of small DNA tumor viruses. We describe here molecular cloning and functional characterization of a fifth member of the E2F family of transcription factors. E2F-5 protein is more homologous to E2F-4 (72% amino acid identity) than to E2F-1, E2F-2, and E2F-3 (35% amino acid identity). Based on structural and functional criteria, the E2F family appears to comprise two distinct sub-families, one composed of E2F-1, E2F-2, and E2F-3 and the other composed of E2F-4 and E2F-5, E2F-5 mRNA is expressed in a wide variety of human tissues. The protein is expressed as multiple species ranging in size from 46 to 54 kDa as a result of differential phosphorylation. The expression of a reporter gene containing E2F binding sites in the promoter is transcriptionally activated by E2F-5 in a cooperative manner with the DP-1 protein. The interaction between E2F-5 and DP-1 is demonstrated using a two-hybrid system in mammalian cells. We have also demonstrated the presence of a strong transactivation domain at the carboxy terminus (273-346 amino acid residues) of E2F-5 protein.
AB - The E2F activity plays a critical role in the control of cell cycle and action of tumor suppressor proteins and is also a target of the transforming proteins of small DNA tumor viruses. We describe here molecular cloning and functional characterization of a fifth member of the E2F family of transcription factors. E2F-5 protein is more homologous to E2F-4 (72% amino acid identity) than to E2F-1, E2F-2, and E2F-3 (35% amino acid identity). Based on structural and functional criteria, the E2F family appears to comprise two distinct sub-families, one composed of E2F-1, E2F-2, and E2F-3 and the other composed of E2F-4 and E2F-5, E2F-5 mRNA is expressed in a wide variety of human tissues. The protein is expressed as multiple species ranging in size from 46 to 54 kDa as a result of differential phosphorylation. The expression of a reporter gene containing E2F binding sites in the promoter is transcriptionally activated by E2F-5 in a cooperative manner with the DP-1 protein. The interaction between E2F-5 and DP-1 is demonstrated using a two-hybrid system in mammalian cells. We have also demonstrated the presence of a strong transactivation domain at the carboxy terminus (273-346 amino acid residues) of E2F-5 protein.
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U2 - 10.1006/bbrc.1997.8010
DO - 10.1006/bbrc.1997.8010
M3 - Article
C2 - 9464260
AN - SCOPUS:0032567651
SN - 0006-291X
VL - 242
SP - 586
EP - 592
JO - Biochemical and biophysical research communications
JF - Biochemical and biophysical research communications
IS - 3
ER -