Atypical E2F Transcription Factors Contributed to Cell Cycle Regulation

Abstract: E2F transcription factors are important elements in cell cycle regulatory network that regulate cell proliferation， differentiation and apoptosis， consequently involved in many physiological and pathological processes. The biological function of E2Fs has been widely investigated in mammals. The recent identified atypical E2F family members of E2F7 and E2F8 in mammals develop a new insight of cellular E2Fs function. Compared to the typical E2Fs， atypical E2F proteins have the duplication of DNA-binding domain and regulate gene expression independent of dimerization partner protein. Nuclear localized atypical E2F proteins act as transcription inhibitory factors on typical E2F-driven target genes and modulate cell cycle progression， and play a crucial role in cell size determination， polyploidization， cell proliferation， differentiation and apoptosis. The establishment and improvement of knockout mice model make it possible for us to study the physiological function of atypical E2Fs in specific tissues and organs. Atypical E2Fs function in regulating embryonic development， angiogenesis and hematopoiesis. In addition， change of the expression levels of typical E2Fs and atypical E2Fs correlates with tumorigenesis in humans. This review summarized the latest advances in the studies on expression， regulation and function of atypical E2F transcription factors in physiological and pathological processes.

CSTR: 32200.14.cjcb.2014.07.0023