Mencía Mario, Moqtaderi Zarmik, Geisberg Joseph V, Kuras Laurent, Struhl Kevin
Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
Mol Cell. 2002 Apr;9(4):823-33. doi: 10.1016/s1097-2765(02)00490-2.
In yeast, TFIID strongly associates with nearly all ribosomal protein (RP) promoters, but a TAF-independent form of TBP preferentially associates with other active promoters. RP promoters are regulated in response to growth stimuli, in most cases by a Rap1-containing activator. This Rap1-dependent activator is necessary and sufficient for TFIID recruitment, whereas other activators do not efficiently recruit TFIID. TAFs are recruited to RP promoters even when TBP and other general transcription factors are not associated, suggesting that TFIID recruitment involves a direct activator-TAF interaction. Most RP promoters lack canonical TATA elements, and they are preferentially activated by the Rap1-containing activator. These results demonstrate activator-specific recruitment of TFIID in vivo, and they suggest that TFIID recruitment is important for coordinate expression of RP genes.
在酵母中，TFIID与几乎所有核糖体蛋白（RP）启动子紧密结合，但一种不依赖TAF的TBP形式优先与其他活性启动子结合。RP启动子响应生长刺激而受到调控，在大多数情况下由含Rap1的激活因子调控。这种依赖Rap1的激活因子对于TFIID的招募是必要且充分的，而其他激活因子不能有效地招募TFIID。即使TBP和其他通用转录因子不结合，TAFs也会被招募到RP启动子，这表明TFIID的招募涉及激活因子与TAF的直接相互作用。大多数RP启动子缺乏典型的TATA元件，它们优先被含Rap1的激活因子激活。这些结果证明了体内TFIID的激活因子特异性招募，并且表明TFIID的招募对于RP基因的协调表达很重要。
