2ja7: Difference between revisions
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==Overview== | ==Overview== | ||
Cells use transcription-coupled repair (TCR) to efficiently eliminate DNA, lesions such as ultraviolet light-induced cyclobutane pyrimidine dimers, (CPDs). Here we present the structure-based mechanism for the first step, in eukaryotic TCR, CPD-induced stalling of RNA polymerase (Pol) II. A CPD, in the transcribed strand slowly passes a translocation barrier and enters, the polymerase active site. The CPD 5'-thymine then directs uridine, misincorporation into messenger RNA, which blocks translocation., Artificial replacement of the uridine by adenosine enables CPD bypass;, thus, Pol II stalling requires CPD-directed misincorporation. In the, stalled complex, the lesion is inaccessible, and the polymerase, conformation is unchanged. This is consistent with nonallosteric, recruitment of . | Cells use transcription-coupled repair (TCR) to efficiently eliminate DNA, lesions such as ultraviolet light-induced cyclobutane pyrimidine dimers, (CPDs). Here we present the structure-based mechanism for the first step, in eukaryotic TCR, CPD-induced stalling of RNA polymerase (Pol) II. A CPD, in the transcribed strand slowly passes a translocation barrier and enters, the polymerase active site. The CPD 5'-thymine then directs uridine, misincorporation into messenger RNA, which blocks translocation., Artificial replacement of the uridine by adenosine enables CPD bypass;, thus, Pol II stalling requires CPD-directed misincorporation. In the, stalled complex, the lesion is inaccessible, and the polymerase, conformation is unchanged. This is consistent with nonallosteric, recruitment of repair factors and excision of a lesion-containing DNA, fragment in the presence of Pol II. | ||
==About this Structure== | ==About this Structure== | ||
2JA7 is a | 2JA7 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with MG and ZN as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/DNA-directed_RNA_polymerase DNA-directed RNA polymerase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.7.6 2.7.7.6] Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2JA7 OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: zinc-finger]] | [[Category: zinc-finger]] | ||
''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 12:30:02 2007'' | ||