Substrate twinning activates the signal recognition particle and its receptor

Pascal F. Egea (), Shu-ou Shan, Johanna Napetschnig, David F. Savage, Peter Walter and Robert M. Stroud ()
Additional contact information
Pascal F. Egea: University of California at San Francisco
Shu-ou Shan: University of California at San Francisco
Johanna Napetschnig: University of California at San Francisco
David F. Savage: University of California at San Francisco
Peter Walter: University of California at San Francisco
Robert M. Stroud: University of California at San Francisco

Nature, 2004, vol. 427, issue 6971, 215-221

Abstract: Abstract Signal sequences target proteins for secretion from cells or for integration into cell membranes. As nascent proteins emerge from the ribosome, signal sequences are recognized by the signal recognition particle (SRP), which subsequently associates with its receptor (SR). In this complex, the SRP and SR stimulate each other's GTPase activity, and GTP hydrolysis ensures unidirectional targeting of cargo through a translocation pore in the membrane. To define the mechanism of reciprocal activation, we determined the 1.9 Å structure of the complex formed between these two GTPases. The two partners form a quasi-two-fold symmetrical heterodimer. Biochemical analysis supports the importance of the extensive interaction surface. Complex formation aligns the two GTP molecules in a symmetrical, composite active site, and the 3′OH groups are essential for association, reciprocal activation and catalysis. This unique circle of twinned interactions is severed twice on hydrolysis, leading to complex dissociation after cargo delivery.

Date: 2004
References: Add references at CitEc
Citations: View citations in EconPapers (2)

Downloads: (external link)
https://www.nature.com/articles/nature02250 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:nature:v:427:y:2004:i:6971:d:10.1038_nature02250

Ordering information: This journal article can be ordered from
https://www.nature.com/

DOI: 10.1038/nature02250

Access Statistics for this article

Nature is currently edited by Magdalena Skipper

More articles in Nature from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().