3JCN

Structures of ribosome-bound initiation factor 2 reveal the mechanism of subunit association: Initiation Complex I

This is a non-PDB format compatible entry.

Summary for 3JCN

• Entry DOI: 10.2210/pdb3jcn/pdb
• Related: 3JCJ
• EMDB information: 3285 6559
• Descriptor: 50S ribosomal protein L32, 50S ribosomal protein L4, 50S ribosomal protein L5, ... (57 entities in total)
• Functional Keywords: ribosome, translation initiation, gtpase, 70s, bacterial ribosome, if2, initiation factor 2
• Biological source: Escherichia coli; More
• Total number of polymer chains: 55
• Total formula weight: 2271067.66

Authors

Sprink, T.,Ramrath, D.J.F.,Yamamoto, H.,Yamamoto, K.,Loerke, J.,Ismer, J.,Hildebrand, P.W.,Scheerer, P.,Buerger, J.,Mielke, T.,Spahn, C.M.T. (deposition date: 2016-01-04, release date: 2016-03-09, Last modification date: 2018-07-18)

Primary citation

Sprink, T.,Ramrath, D.J.,Yamamoto, H.,Yamamoto, K.,Loerke, J.,Ismer, J.,Hildebrand, P.W.,Scheerer, P.,Burger, J.,Mielke, T.,Spahn, C.M.
Structures of ribosome-bound initiation factor 2 reveal the mechanism of subunit association.
Sci Adv, 2:e1501502-e1501502, 2016

PubMed Abstract: Throughout the four phases of protein biosynthesis-initiation, elongation, termination, and recycling-the ribosome is controlled and regulated by at least one specified translational guanosine triphosphatase (trGTPase). Although the structural basis for trGTPase interaction with the ribosome has been solved for the last three steps of translation, the high-resolution structure for the key initiation trGTPase, initiation factor 2 (IF2), complexed with the ribosome, remains elusive. We determine the structure of IF2 complexed with a nonhydrolyzable guanosine triphosphate analog and initiator fMet-tRNAi (Met) in the context of the Escherichia coli ribosome to 3.7-Å resolution using cryo-electron microscopy. The structural analysis reveals previously unseen intrinsic conformational modes of the 70S initiation complex, establishing the mutual interplay of IF2 and initator transfer RNA (tRNA) with the ribsosome and providing the structural foundation for a mechanistic understanding of the final steps of translation initiation.

PubMed: 26973877
DOI: 10.1126/sciadv.1501502

Experimental method

ELECTRON MICROSCOPY (4.6 Å)