8B0I

CryoEM structure of bacterial RapZ.GlmZ complex central to the control of cell envelope biogenesis

Summary for 8B0I

• Entry DOI: 10.2210/pdb8b0i/pdb
• EMDB information: 15784
• Descriptor: RNase adapter protein RapZ, GlmZ small regulatory RNA (2 entities in total)
• Functional Keywords: endonuclease rnase e, adaptor protein rapz, small regulatory rna glmz, rna binding protein
• Biological source: Escherichia coli K-12; More
• Total number of polymer chains: 5
• Total formula weight: 196215.14

Authors

Islam, M.S.,Hardwick, H.W.,Chirgadze, D.Y.,Luisi, B.F. (deposition date: 2022-09-07, release date: 2022-10-05, Last modification date: 2024-07-24)

Primary citation

Islam, M.S.,Hardwick, S.W.,Quell, L.,Durica-Mitic, S.,Chirgadze, D.Y.,Gorke, B.,Luisi, B.F.
Structure of a bacterial ribonucleoprotein complex central to the control of cell envelope biogenesis.
Embo J., 42:e112574-e112574, 2023

PubMed Abstract: Biogenesis of the essential precursor of the bacterial cell envelope, glucosamine-6-phosphate (GlcN6P), is controlled by intricate post-transcriptional networks mediated by GlmZ, a small regulatory RNA (sRNA). GlmZ stimulates translation of the mRNA encoding GlcN6P synthtase in Escherichia coli, but when bound by RapZ protein, the sRNA becomes inactivated through cleavage by the endoribonuclease RNase E. Here, we report the cryoEM structure of the RapZ:GlmZ complex, revealing a complementary match of the RapZ tetrameric quaternary structure to structural repeats in the sRNA. The nucleic acid is contacted by RapZ mostly through a highly conserved domain that shares an evolutionary relationship with phosphofructokinase and suggests links between metabolism and riboregulation. We also present the structure of a precleavage intermediate formed between the binary RapZ:GlmZ complex and RNase E that reveals how GlmZ is presented and recognised by the enzyme. The structures provide a framework for understanding how other encounter complexes might guide recognition and action of endoribonucleases on target transcripts, and how structured substrates in polycistronic precursors may be recognised for processing by RNase E.

PubMed: 36504162
DOI: 10.15252/embj.2022112574

Experimental method

ELECTRON MICROSCOPY (4.28 Å)