Miyao T, Honda A, Qu Z, Ishihama A
National Institute of Genetics, Department of Molecular Genetics, Mishima, Shizuoka, Japan.
Mol Gen Genet. 1998 Jul;259(1):123-9. doi: 10.1007/s004380050796.
[Rpb1 and Rpb2] Mapping of the contact sites on two large subunits of the fission yeast Schizosaccharomyces pombe RNA polymerase II with two small subunits, Rpb3 and Rpb5, was carried out using the two-hybrid screening system in the budding yeast Saccharomyces cerevisiae. Rpb5 was found to interact with any fragment of Rpb1 that contained the region H, which is conserved among the subunit 1 homologues of all RNA polymerases, including the beta' subunit of prokaryotic RNA polymerases. In agreement with the fact that Rpb5 is shared among all three forms of eukaryotic RNA polymerases, the region H of RNA polymerase I subunit 1 (Rpa190) was also found to interact with Rpb5. On the other hand, two-hybrid screening of Rpb2 fragments from RNA polymerase II indicated the presence of an Rpb3 contact site in the region H which is conserved among the subunit 2 homologues of all RNA polymerases, including the beta subunit of prokaryotic RNA polymerases. Possible functions of the regions H in the subunits 1 and 2 are discussed.
[Rpb1和Rpb2] 利用酿酒酵母中的双杂交筛选系统，对粟酒裂殖酵母RNA聚合酶II的两个大亚基与两个小亚基Rpb3和Rpb5之间的接触位点进行了定位。发现Rpb5可与Rpb1中包含区域H的任何片段相互作用，该区域在所有RNA聚合酶的亚基1同源物中保守，包括原核RNA聚合酶的β'亚基。鉴于Rpb5在所有三种真核RNA聚合酶中都存在，还发现RNA聚合酶I亚基1（Rpa190）的区域H也与Rpb5相互作用。另一方面，对RNA聚合酶II的Rpb2片段进行双杂交筛选表明，在区域H中存在一个Rpb3接触位点，该区域在所有RNA聚合酶的亚基2同源物中保守，包括原核RNA聚合酶的β亚基。文中讨论了区域H在亚基1和2中的可能功能。
