Related Experiment Video
Updated: Aug 16, 2026

Prediction and Validation of Gene Regulatory Elements Activated During Retinoic Acid Induced Embryonic Stem Cell Differentiation
Published on: June 21, 2016
A stimulatory RNA associated with RecBCD enzyme
S K Amundsen1, A F Taylor, G R Smith
1Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue North, A1-162, PO Box 19024, Seattle, WA 98109, USA.
Abstract:
RecBCD enzyme acts in the major pathway of homologous recombination of linear DNA in Escherichia coli. The enzyme unwinds DNA and is an ATP-dependent double-strand and single-strand exonuclease and a single-strand endonuclease; it acts at Chi recombination hotspots (5'-GCTGGTGG-3') to produce a recombinogenic single-stranded DNA 3'-end. We found that a small RNA with a unique sequence of approximately 24 nt was tightly bound to RecBCD enzyme and co-purified with it. When added to native enzyme this RNA, but not four others, increased DNA unwinding and Chi nicking activities of the enzyme. In seven similarly active enzyme preparations the molar ratio of RNA molecules to RecBCD enzyme molecules ranged from 0.2 to <0.008. These results suggest that, although this unique RNA is not an essential enzyme subunit, it has a biological role in stimulating RecBCD enzyme activity.
Related Concept Videos
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
RNA Polymerase II Accessory Proteins
Co-activators and Co-repressors
Bacterial Transcription
Transcription can be divided into three main stages, each involving distinct DNA sequences to guide the polymerase. These are:
Bacterial RNA Polymerase
In most genes, the transcription site is a single base present upstream of the coding sequence. Though RNAP is a catalytically efficient enzyme, it does not recognize...
RNA Polymerase II Accessory Proteins

