Structural highlights
Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe eukaryotic translation initiation factor 4A (eIF4A) is a member of the DEA(D/H)-box RNA helicase family, a diverse group of proteins that couples an ATPase activity to RNA binding and unwinding. Previous work has provided the structure of the amino-terminal, ATP-binding domain of eIF4A. Extending those results, we have solved the structure of the carboxyl-terminal domain of eIF4A with data to 1.75 A resolution; it has a parallel alpha-beta topology that superimposes, with minor variations, on the structures and conserved motifs of the equivalent domain in other, distantly related helicases. Using data to 2.8 A resolution and molecular replacement with the refined model of the carboxyl-terminal domain, we have completed the structure of full-length eIF4A; it is a "dumbbell" structure consisting of two compact domains connected by an extended linker. By using the structures of other helicases as a template, compact structures can be modeled for eIF4A that suggest (i) helicase motif IV binds RNA; (ii) Arg-298, which is conserved in the DEA(D/H)-box RNA helicase family but is absent from many other helicases, also binds RNA; and (iii) motifs V and VI "link" the carboxyl-terminal domain to the amino-terminal domain through interactions with ATP and the DEA(D/H) motif, providing a mechanism for coupling ATP binding and hydrolysis with conformational changes that modulate RNA binding. Crystal structure of yeast initiation factor 4A, a DEAD-box RNA helicase.,Caruthers JM, Johnson ER, McKay DB Proc Natl Acad Sci U S A. 2000 Nov 21;97(24):13080-5. PMID:11087862[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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