Snapshots of the RNA processing factor SCAF8 bound to different phosphorylated forms of the carboxyl- terminal domain of RNA polymerase II
Snapshots of the RNA processing factor SCAF8 bound to different phosphorylated forms of the carboxyl- terminal domain of RNA polymerase II
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DOI：
10.1074/jbc.m803540200
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发表时间：
2008-08-15
影响因子：
4.8
通讯作者：
Meinhart, Anton
中科院分区：
文献类型：
--
作者：
Becker, Roland;Loll, Bernhard;Meinhart, Anton
伴随着RNA聚合酶II（Pol II）转录，RNA成熟因子被募集到Pol II的羧基末端结构域（CTD），其磷酸化状态在转录周期期间改变。CTD磷酸化触发参与RNA加工和转录终止的功能不同的因子的募集;这些因子中的大多数具有保守的CTD相互作用结构域（CID）。因子募集的证实被认为是通过CID识别CTD的不同磷酸化形式来进行的。我们发现，人RNA加工因子SCAF 8与Pol II的非磷酸化CTD相互作用较弱。在磷酸化后，对CTD的亲和力增加;然而，SCAF 8对CTD上的磷酸化模式是混杂的。采用结构和生物物理相结合的方法，我们能够区分CID内的基序，涉及一个通用的CTD序列识别的项目，赋予磷酸特异性。
Concomitant with RNA polymerase II (Pol II) transcription, RNA maturation factors are recruited to the carboxyl- terminal domain (CTD) of Pol II, whose phosphorylation state changes during a transcription cycle. CTD phosphorylation triggers recruitment of functionally different factors involved in RNA processing and transcription termination; most of these factors harbor a conserved CTD interacting domain (CID). Orchestration of factor recruitment is believed to be conducted by CID recognition of distinct phosphorylated forms of the CTD. We show that the human RNA processing factor SCAF8 interacts weakly with the unphosphorylated CTD of Pol II. Upon phosphorylation, affinity for the CTD is increased; however, SCAF8 is promiscuous to the phosphorylation pattern on the CTD. Employing a combined structural and biophysical approach, we were able to distinguish motifs within CIDs that are involved in a generic CTD sequence recognition from items that confer phospho-specificity.