Hanes Steven D
Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, 750 E Adams St., Syracuse, NY 13210, USA.
Biochim Biophys Acta. 2014;1839(4):316-33. doi: 10.1016/j.bbagrm.2014.02.001. Epub 2014 Feb 12.
Ess1 is a prolyl isomerase that regulates the structure and function of eukaryotic RNA polymerase II. Ess1 works by catalyzing the cis/trans conversion of pSer5-Pro6 bonds, and to a lesser extent pSer2-Pro3 bonds, within the carboxy-terminal domain (CTD) of Rpb1, the largest subunit of RNA pol II. Ess1 is conserved in organisms ranging from yeast to humans. In budding yeast, Ess1 is essential for growth and is required for efficient transcription initiation and termination, RNA processing, and suppression of cryptic transcription. In mammals, Ess1 (called Pin1) functions in a variety of pathways, including transcription, but it is not essential. Recent work has shown that Ess1 coordinates the binding and release of CTD-binding proteins that function as co-factors in the RNA pol II complex. In this way, Ess1 plays an integral role in writing (and reading) the so-called CTD code to promote production of mature RNA pol II transcripts including non-coding RNAs and mRNAs.
Ess1是一种脯氨酰异构酶，可调节真核生物RNA聚合酶II的结构和功能。Ess1通过催化RNA聚合酶II最大亚基Rpb1的羧基末端结构域（CTD）内pSer5-Pro6键的顺式/反式转换，以及在较小程度上催化pSer2-Pro3键的转换来发挥作用。Ess1在从酵母到人类的生物体中都是保守的。在芽殖酵母中，Ess1对生长至关重要，是高效转录起始和终止、RNA加工以及隐秘转录抑制所必需的。在哺乳动物中，Ess1（称为Pin1）在包括转录在内的多种途径中发挥作用，但并非必不可少。最近的研究表明，Ess1协调CTD结合蛋白的结合和释放，这些蛋白在RNA聚合酶II复合物中作为辅助因子发挥作用。通过这种方式，Ess1在书写（和读取）所谓的CTD密码以促进包括非编码RNA和mRNA在内的成熟RNA聚合酶II转录本的产生中发挥不可或缺的作用。
