Bertolotti A, Lutz Y, Heard D J, Chambon P, Tora L
Institut de Génétique et de Biologie Moléculaire et Cellulaire CNRS/INSERM/ULP, Illkirch, France.
EMBO J. 1996 Sep 16;15(18):5022-31.
TFIID is the main sequence-specific DNA-binding component of the RNA polymerase II (Pol II) transcriptional machinery. It is a multiprotein complex composed of the TATA-binding protein (TBP) and TBP-associated factors (TAF(II)s). Here we report the cloning and characterization of a novel human TBP-associated factor, hTAF(II)68. It contains a consensus RNA-binding domain (RNP-CS) and binds not only RNA, but also single stranded (ss) DNA. hTAF(II)68 shares extensive sequence similarity with TLS/FUS and EWS, two human nuclear RNA-binding pro-oncoproteins which are products of genes commonly translocated in human sarcomas. Like hTAF(II)68, TLS/FUS is also associated with a sub-population of TFIID complexes chromatographically separable from those containing hTAF(II)68. Therefore, these RNA and/or ssDNA-binding proteins may play specific roles during transcription initiation at distinct promoters. Moreover, we demonstrate that hTAF(II)68 co-purifies also with the human RNA polymerase II and can enter the preinitiation complex together with Pol II.
TFIID是RNA聚合酶II（Pol II）转录机制中主要的序列特异性DNA结合成分。它是一种由TATA结合蛋白（TBP）和TBP相关因子（TAF（II）s）组成的多蛋白复合物。在此，我们报告了一种新型人类TBP相关因子hTAF（II）68的克隆与鉴定。它包含一个共有RNA结合结构域（RNP-CS），不仅能结合RNA，还能结合单链（ss）DNA。hTAF（II）68与TLS/FUS和EWS具有广泛的序列相似性，后两者是人类核RNA结合原癌蛋白，是人类肉瘤中常见的基因易位产物。与hTAF（II）68一样，TLS/FUS也与一部分可通过色谱法与含有hTAF（II）68的复合物分离的TFIID复合物相关。因此，这些RNA和/或ssDNA结合蛋白可能在不同启动子的转录起始过程中发挥特定作用。此外，我们证明hTAF（II）68也与人RNA聚合酶II共纯化，并能与Pol II一起进入起始前复合物。
