Business Research

Cell, Vol. 54, 1033-1042,

September

23, 1988, Copyright

0 1988 by Cell Press

Transcription Factor ATF Interacts with the TATA Factor to Facilitate Establishment of a Preinitiation Complex

Masami Horikoshi,” Tsonwin Hai,t Young-Sun Lin,t Michael R. Green,t and Robert G. Roeder” * Laboratory of Biochemistry and Molecular Biology The Rockefeller University New York, New York 10021 fDepartment of Biochemistry and Molecular Biology Harvard University Cambridge, Massachusetts 02138 curate initiation in crude extracts from nonspecialized (HeLa) cells, indicating the presence of core promoter elements and ubiquitous factors with an intrinsic affinity for these elements (reviewed in Nakajima et al., 1988). Later studies showed enhanced transcription in crude extracts in response to upstream promoter and enhancer elements and associated factors, including both ubiquitous (reviewed in Miyamoto et al., 1985) and tissue-specific (MizushimaSugano and Roeder, 1986; Suzuki et al., 1986; Gorski et al., 1986) or induced (Heintz and Roeder, 1984; Top01 et al., 1985) factors. These experiments strongly suggest that upstream elements and associated factors stimulate transcription by facilitating functional interactions of the core promoter factors under conditions where these interactions are rate limiting. The fact that core promoter function is not generally observed in vivo in the absence of upstream elements or other activating factors indicates that these interactions are severely limiting under these conditions, which may not always be the case in vitro. Various kinetic and inhibitor studies in mammalian cell free systems have suggested a number of steps and corresponding preinitiation complexes in transcription initiation (Davison et al., 1983; Fire et al., 1984; Hawley and Roeder, 19851987; Reinberg and Roeder, 1987; Reinberg et al., 1987). At the same time, purification studies have led to the identification of a number of factors that are necessary and sufficient...