PDBsum entry 4hht

Hydrolase/DNA

PDB id: 4hht

Contents

Protein chain

220 a.a.

DNA/RNA

Metals

_CA ×2

Waters ×24

PDB id:

4hht

Name:

Hydrolase/DNA

Title:

T. Maritima rnase h2 g21s in complex with nucleic acid substrate and calcium ions

Structure:

Ribonuclease hii. Chain: a. Synonym: rnase hii. Engineered: yes. Mutation: yes. DNA (5'-d( Gp Ap Ap Tp Cp Ap Gp Gp Tp Gp Tp C)-3'). Chain: c. Engineered: yes. Other_details: 12-mer DNA.

Source:

Thermotoga maritima. Organism_taxid: 243274. Strain: atcc 43589 / msb8 / dsm 3109 / jcm 10099. Gene: rnhb, tm_0915. Expressed in: escherichia coli. Expression_system_taxid: 562. Synthetic: yes. Synthetic: yes

Resolution:

3.10Å R-factor: 0.182 R-free: 0.254

Authors:

M.P.Rychlik,M.Nowotny

Key ref:

H.Chon et al. (2013). RNase H2 roles in genome integrity revealed by unlinking its activities. Nucleic Acids Res, 41, 3130-3143. PubMed id: 23355612 DOI: 10.1093/nar/gkt027

Date:

10-Oct-12 Release date: 06-Feb-13

Protein chain

Q9X017  (RNH2_THEMA) -  Ribonuclease HII from Thermotoga maritima (strain ATCC 43589 / DSM 3109 / JCM 10099 / NBRC 100826 / MSB8)

Seq: 238 a.a.

Struc: 220 a.a.*

* PDB and UniProt seqs differ at 1 residue position (black cross)

DNA/RNA chains

G-A-A-T-C-A-G-G-T-G-T-C 12 bases

G-A-C-A-C-C-T-G-A-T-T-C 12 bases

Enzyme reactions

• Enzyme class: E.C.3.1.26.4 - ribonuclease H.
• Reaction: Endonucleolytic cleavage to 5'-phosphomonoester.

DOI no: 10.1093/nar/gkt027

Nucleic Acids Res 41:3130-3143 (2013)

PubMed id: 23355612

RNase H2 roles in genome integrity revealed by unlinking its activities.

H.Chon, J.L.Sparks, M.Rychlik, M.Nowotny, P.M.Burgers, R.J.Crouch, S.M.Cerritelli.

ABSTRACT

Ribonuclease H2 (RNase H2) protects genome integrity by its dual roles of resolving transcription-related R-loops and ribonucleotides incorporated in DNA during replication. To unlink these two functions, we generated a Saccharomyces cerevisiae RNase H2 mutant that can resolve R-loops but cannot cleave single ribonucleotides in DNA. This mutant definitively correlates the 2-5 bp deletions observed in rnh201Δ strains with single rNMPs in DNA. It also establishes a connection between R-loops and Sgs1-mediated replication reinitiation at stalled forks and identifies R-loops uniquely processed by RNase H2. In mouse, deletion of any of the genes coding for RNase H2 results in embryonic lethality, and in humans, RNase H2 hypomorphic mutations cause Aicardi-Goutières syndrome (AGS), a neuroinflammatory disorder. To determine the contribution of R-loops and rNMP in DNA to the defects observed in AGS, we characterized in yeast an AGS-related mutation, which is impaired in processing both substrates, but has sufficient R-loop degradation activity to complement the defects of rnh201Δ sgs1Δ strains. However, this AGS-related mutation accumulates 2-5 bp deletions at a very similar rate as the deletion strain.