title: Unusual, dual endo- and exonuclease activity in the degradosome explained by crystal structure analysis of RNase J1.
abstract: RNase J is an essential enzyme in Bacillus subtilis with unusual dual endonuclease and 5'-to-3' exonuclease activities that play an important role in the maturation and degradation of mRNA. RNase J is also a component of the recently identified "degradosome" of B. subtilis. We report the crystal structure of RNase J1 from B. subtilis to 3.0 Å resolution, analysis of which reveals it to be in an open conformation suitable for binding substrate RNA. RNase J is a member of the β-CASP family of zinc-dependent metallo-β-lactamases. We have exploited this similarity in constructing a model for an RNase J1:RNA complex. Analysis of this model reveals candidate-stacking interactions with conserved aromatic side chains, providing a molecular basis for the observed enzyme activity. Comparisons of the B. subtilis RNase J structure with related enzymes reveal key differences that provide insights into conformational changes during catalysis and the role of the C-terminal domain.
authors: Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle-upon-Tyne NE2 4HH, UK.
authors: Joseph A
authors: JA
authors: Newman
authors: Lorraine
authors: L
authors: Hewitt
authors: Cecilia
authors: C
authors: Rodrigues
authors: Alexandra
authors: A
authors: Solovyova
authors: Colin R
authors: CR
authors: Harwood
authors: Richard J
authors: RJ
authors: Lewis
mesh_terms: D020816:Amino Acid Motifs; D001412:Bacillus subtilis / Q000201:enzymology*; D020134:Catalytic Domain; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D008958:Models, Molecular; D011485:Protein Binding; D054730:Protein Interaction Domains and Motifs; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D012313:RNA / Q000737:chemistry; D012260:Ribonucleases / Q000737:chemistry*; D040681:Structural Homology, Protein
chemical_list: D012313:RNA; D012260:Ribonucleases