During transcription, RNA polymerase (RNAP) supercoils DNA as it translocates. The resulting torsional stress in DNA can accumulate and, in the absence of regulatory mechanisms, becomes a barrier to RNAP elongation, causing RNAP stalling, backtracking, and transcriptional arrest. Here we investigate whether and how a transcription factor may regulate both torque-induced
Transcription is the critical first step in expressing a gene, during which an RNA polymerase (RNAP) synthesizes an RNA copy of one strand of the DNA that encodes a gene. Here we describe a laboratory experiment that uses a single assay to probe two important steps in transcription: (1) RNAP binding to DNA, and (2) the transcriptional activity of the polymerase. Students probe both these steps in a single experiment using a fluorescence‐based electrophoretic mobility shift assay (EMSA) and commercially available
- Award ID(s):
- 1817442
- PAR ID:
- 10403452
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biochemistry and Molecular Biology Education
- Volume:
- 51
- Issue:
- 2
- ISSN:
- 1470-8175
- Page Range / eLocation ID:
- p. 230-235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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