ATP- and activator-responsive steps in RNA polymerase II transcription /
RNA polymerase II transcription is a multi-step process mediated by a large number of proteins and enzymes. Steps in transcription include assembly of the transcription complex, open complex formation, promoter clearance, and elongation. Transcription requires a hydrolyzable source of ATP independen...
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| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
2002.
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| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=726464301&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | RNA polymerase II transcription is a multi-step process mediated by a large number of proteins and enzymes. Steps in transcription include assembly of the transcription complex, open complex formation, promoter clearance, and elongation. Transcription requires a hydrolyzable source of ATP independent from the requirement for ATP as a substrate in RNA synthesis. ATP-mediated activation of transcription complexes can be blocked by addition of an excess of the ATP analog ATPγS, and activated complexes rapidly and reversibly lose the ability to transcribe long RNAs in the presence of ATPγS. This instability of ATP-activated transcription complexes in the presence of ATPγS was used to define ATP-responsive steps in transcription in an in vitro transcription system derived from nuclear extracts of HeLa cells. The ATP requirements for promoter clearance and elongation were completely satisfied prior to initiation of RNA synthesis, while the ATPγS-mediated instability of ATP-activated complexes results from the loss of functional open complexes. To define USF-responsive steps in transcription from the adenovirus major late promoter, potential USF-mediated effects on a number of steps in the overall process of transcription were assessed. Activation by USF in the in vitro system occurs very early in the transcription cycle, most likely by facilitating assembly of the transcription preinitiation complex or affecting open complex formation. |
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| Item Description: | Vita. "Major Subject: Biochemistry". |
| Physical Description: | xiii, 127 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 115-126). |