White R J, Khoo B C, Inostroza J A, Reinberg D, Jackson S P
Wellcome/CRC Institute, University of Cambridge, UK.
Science. 1994 Oct 21;266(5184):448-50. doi: 10.1126/science.7939686.
RNA polymerases I, II, and III each use the TATA-binding protein (TBP). Regulators that target this shared factor may therefore provide a means to coordinate the activities of the three nuclear RNA polymerases. The repressor Dr1 binds to TBP and blocks the interaction of TBP with polymerase II- and polymerase III-specific factors. This enables Dr1 to coordinately regulate transcription by RNA polymerases II and III. Under the same conditions, Dr1 does not inhibit polymerase I transcription. By selectively repressing polymerases II and III, Dr1 may shift the physiological balance of transcriptional output in favor of polymerase I.
RNA聚合酶I、II和III均使用TATA结合蛋白（TBP）。因此，靶向这一共享因子的调控因子可能提供一种协调三种核RNA聚合酶活性的方式。阻遏物Dr1与TBP结合，并阻断TBP与聚合酶II和聚合酶III特异性因子的相互作用。这使得Dr1能够协调调控RNA聚合酶II和III的转录。在相同条件下，Dr1并不抑制聚合酶I的转录。通过选择性抑制聚合酶II和III，Dr1可能会使转录输出的生理平衡朝着有利于聚合酶I的方向转变。
