4KJI

Novel re-arrangement of an RsmA/cSRa family protein to create a structurally distinct new RNA-binding family member

Summary for 4KJI

• Entry DOI: 10.2210/pdb4kji/pdb
• Descriptor: RsmN, a RNA-binding protein of Regulator of Secondary Metabolism, RsmZ-2 (2 entities in total)
• Functional Keywords: protein-rna complex, beta barrel, beta-barrel, post-transcriptional regulation, rna binding, rna binding protein-rna complex, rna binding protein/rna
• Biological source: Pseudomonas aeruginosa; More
• Total number of polymer chains: 4
• Total formula weight: 27918.57

Authors

Li, C. (deposition date: 2013-05-03, release date: 2013-09-04, Last modification date: 2023-09-20)

Primary citation

Morris, E.R.,Hall, G.,Li, C.,Heeb, S.,Kulkarni, R.V.,Lovelock, L.,Silistre, H.,Messina, M.,Camara, M.,Emsley, J.,Williams, P.,Searle, M.S.
Structural Rearrangement in an RsmA/CsrA Ortholog of Pseudomonas aeruginosa Creates a Dimeric RNA-Binding Protein, RsmN.
Structure, 21:1659-1671, 2013

PubMed Abstract: In bacteria, the highly conserved RsmA/CsrA family of RNA-binding proteins functions as global posttranscriptional regulators acting on mRNA translation and stability. Through phenotypic complementation of an rsmA mutant in Pseudomonas aeruginosa, we discovered a family member, termed RsmN. Elucidation of the RsmN crystal structure and that of the complex with a hairpin from the sRNA, RsmZ, reveals a uniquely inserted α helix, which redirects the polypeptide chain to form a distinctly different protein fold to the domain-swapped dimeric structure of RsmA homologs. The overall β sheet structure required for RNA recognition is, however, preserved with compensatory sequence and structure differences, allowing the RsmN dimer to target binding motifs in both structured hairpin loops and flexible disordered RNAs. Phylogenetic analysis indicates that, although RsmN appears unique to P. aeruginosa, homologous proteins with the inserted α helix are more widespread and arose as a consequence of a gene duplication event.

PubMed: 23954502
DOI: 10.1016/j.str.2013.07.007

Experimental method

X-RAY DIFFRACTION (3.2 Å)