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Updated: Feb 26, 2026
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DNA-Tethered RNA Polymerase for Programmable In vitro Transcription and Molecular Computation
Published on: December 29, 2021
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RNA polymerase structure and function at lac operon
Sergei Borukhov1, Jookyung Lee
1Department of Cell Biology, UMDNJ-SOM at Stratford, Stratford, NJ 08084, USA. serbor@aol.com
Comptes Rendus Biologies
|June 14, 2005
Summary
Recent studies reveal how RNA polymerase (RNAP) transcription of the E. coli lac operon is regulated. Structural and biochemical insights into RNAP complexes with CRP and lac promoter are discussed.
Area of Science:
- Molecular Biology
- Biochemistry
- Structural Biology
Background:
- The E. coli lac operon is a model system for gene regulation.
- RNA polymerase (RNAP) activity is modulated by transcription factors.
- Cyclic AMP-receptor protein (CRP) activates, while lac-repressor (LacI) inhibits transcription.
Purpose of the Study:
- To review recent structural and biochemical studies of RNAP.
- To elucidate the mechanisms of CRP and LacI regulation of lac operon transcription.
Main Methods:
- Structural analysis of RNAP and its complexes.
- Biochemical assays to study enzyme function.
- Modeling of binary and ternary elongation complexes.
Main Results:
- Structural data for RNAP and elongation complexes are available.
- Interactions between RNAP, CRP, and lac promoter can be modeled.
- Inferences on the molecular mechanisms of transcriptional regulation.
Conclusions:
- Recent structural and biochemical data advance understanding of lac operon regulation.
- Models of RNAP complexes provide mechanistic insights into transcription activation and repression.
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