Structural highlights
Function
[GREA_ECOLI] Necessary for efficient RNA polymerase transcription elongation past template-encoded arresting sites. The arresting sites in DNA have the property of trapping a certain fraction of elongating RNA polymerases that pass through, resulting in locked ternary complexes. Cleavage of the nascent transcript by cleavage factors such as GreA or GreB allows the resumption of elongation from the new 3'terminus. GreA releases sequences of 2 to 3 nucleotides.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Transcription elongation factors stimulate the activity of DNA-dependent RNA polymerases by increasing the overall elongation rate and the completion of RNA chains. One group of such factors, which includes Escherichia coli GreA, GreB and eukaryotic SII (TFIIS), acts by inducing hydrolytic cleavage of the transcript within the RNA polymerase, followed by release of the 3'-terminal fragment. Here we report the crystal structure of GreA at 2.2 A resolution. The structure contains an amino-terminal domain consisting of an antiparallel alpha-helical coiled-coil dimer which extends into solution, reminiscent of the coiled coil in seryl-tRNA synthetases. A site near the tip of the coiled-coil 'finger' plays a direct role in the transcript cleavage reaction by contacting the 3'-end of the transcript. The structure exhibits an unusual asymmetric charge distribution which indicates the manner in which GreA interacts with the RNA polymerase elongation complex.
Crystal structure of the GreA transcript cleavage factor from Escherichia coli.,Stebbins CE, Borukhov S, Orlova M, Polyakov A, Goldfarb A, Darst SA Nature. 1995 Feb 16;373(6515):636-40. PMID:7854424[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Stebbins CE, Borukhov S, Orlova M, Polyakov A, Goldfarb A, Darst SA. Crystal structure of the GreA transcript cleavage factor from Escherichia coli. Nature. 1995 Feb 16;373(6515):636-40. PMID:7854424 doi:http://dx.doi.org/10.1038/373636a0
