TY - JOUR
T1 - Synergistic interactions between heterologous upstream activation elements and specific TATA sequences in a muscle-specific promoter
AU - Grayson, J.
AU - Williams, R. S.
AU - Yu, Y. T.
AU - Bassel-Duby, R.
PY - 1995/4
Y1 - 1995/4
N2 - Previous investigations have defined three upstream activation element- CAC, A/T, and TATA sequences-necessary for muscle-specific transcription of the myoglobin gene. In the present study, we demonstrate that these three sequence elements, prepared as synthetic oligonucleotide cassettes, function synergistically to constitute a cell-type-specific transcription unit. Previously, cognate binding factors that recognize the CCAC and TATA elements were identified. In this study we determine that the A/T element binds two nuclear factors, including myocyte enhancer factor-2 (MEF-2) and an apparently unknown factor we provisionally termed ATF35 (A/T-binding factor, 35 kDa). Mutations that alter in vitro binding of either MEF-2 or ATF35 to this site diminish promoter function in vivo. Functional synergism between factors binding the CCAC and A/T elements is sensitive to subtle mutations in the TATA sequence, recapitulating the unusual preference for specific TATA variants exhibited by the native myoglobin promoter. These results provide new insights into mechanisms that underlie the distinctive pattern of myoglobin gene regulation in mammalian muscle development and lay a foundation for further studies to elucidate general principles of transcriptional control of complex mammalian promoters through combinatorial actions of heterologous transcription factors.
AB - Previous investigations have defined three upstream activation element- CAC, A/T, and TATA sequences-necessary for muscle-specific transcription of the myoglobin gene. In the present study, we demonstrate that these three sequence elements, prepared as synthetic oligonucleotide cassettes, function synergistically to constitute a cell-type-specific transcription unit. Previously, cognate binding factors that recognize the CCAC and TATA elements were identified. In this study we determine that the A/T element binds two nuclear factors, including myocyte enhancer factor-2 (MEF-2) and an apparently unknown factor we provisionally termed ATF35 (A/T-binding factor, 35 kDa). Mutations that alter in vitro binding of either MEF-2 or ATF35 to this site diminish promoter function in vivo. Functional synergism between factors binding the CCAC and A/T elements is sensitive to subtle mutations in the TATA sequence, recapitulating the unusual preference for specific TATA variants exhibited by the native myoglobin promoter. These results provide new insights into mechanisms that underlie the distinctive pattern of myoglobin gene regulation in mammalian muscle development and lay a foundation for further studies to elucidate general principles of transcriptional control of complex mammalian promoters through combinatorial actions of heterologous transcription factors.
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U2 - 10.1128/MCB.15.4.1870
DO - 10.1128/MCB.15.4.1870
M3 - Article
C2 - 7891680
AN - SCOPUS:0028943684
SN - 0270-7306
VL - 15
SP - 1870
EP - 1878
JO - Molecular and cellular biology
JF - Molecular and cellular biology
IS - 4
ER -