This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
4py5
From Proteopedia
Revision as of 05:55, 27 August 2014 by OCA (Talk | contribs)
RNases H participate in the replication and maintenance of genomic DNA. RNase H1 cleaves the RNA strand of RNA/DNA hybrids, and RNase H2 in addition hydrolyzes the RNA residue of RNA-DNA junctions. RNase H3 is structurally closely related to RNases H2, but its biochemical properties are similar to type 1 enzymes. Its unique N-terminal substrate-binding domain (N-domain) is related to TATA-binding protein. Here, we report the first crystal structure of RNase H3 in complex with its RNA/DNA substrate. Just like RNases H1, type 3 enzyme recognizes the 2'-OH groups of the RNA strand and detects the DNA strand by binding a phosphate group and inducing B-form conformation. Moreover, the N-domain recognizes RNA and DNA in a manner that is highly similar to the hybrid-binding domain of RNases H1. Our structure demonstrates a remarkable example of parallel evolution of the elements used in the specific recognition of RNA and DNA.
Crystal structure of RNase H3-substrate complex reveals parallel evolution of RNA/DNA hybrid recognition.,Figiel M, Nowotny M Nucleic Acids Res. 2014 Jul 12. pii: gku615. PMID:25016521[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Figiel M, Nowotny M. Crystal structure of RNase H3-substrate complex reveals parallel evolution of RNA/DNA hybrid recognition. Nucleic Acids Res. 2014 Jul 12. pii: gku615. PMID:25016521 doi:http://dx.doi.org/10.1093/nar/gku615
