Transcriptional activators in yeast.
Eukaryotic transcription activation domains (ADs) are not well defined on the proteome scale. We systematicallly tested approximately 6000 yeast proteins for transcriptional activity using a yeast one-hybrid system and identified 451 transcriptional activators. We then determined their transcription activation strength using fusions to the Gal4 DNA-binding domain and a His3 reporter gene which contained a promoter with a Gal4-binding site. Among the 132 strongest activators 32 are known transcription factors while another 35 have no known function. Although zinc fingers, helix-loop-helix domains and several other domains are highly overrepresented among the activators, only few contain characterized ADs. We also found some striking correlations: the stronger the activation activity, the more acidic, glutamine-rich, proline-rich or asparagine-rich the activators were. About 29% of the activators have been found previously to specifically interact with the transcription machinery, while 10% are known to be components of transcription regulatory complexes. Based on their transcriptional activity, localization and interaction patterns, at least six previously uncharacterized proteins are suggested to be bona fide transcriptional regulators (namely YFL049W, YJR070C, YDR520C, YGL066W/Sgf73, YKR064W and YCR082W/Ahc2).
Titz
Björn
B
Institut für Genetik, Forschungszentrum Karlsruhe, Box 3640, D-76021 Karlsruhe, Germany.
Thomas
Sindhu
S
Rajagopala
Seesandra V
SV
Chiba
Tomoko
T
Ito
Takashi
T
Uetz
Peter
P
D000596:Amino Acids / Q000032:analysis; D002467:Cell Nucleus / Q000737:chemistry; D017434:Protein Structure, Tertiary; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D015534:Trans-Activators / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D015533:Transcriptional Activation; D020798:Two-Hybrid System Techniques
D000596:Amino Acids; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators