Protein Translocation: Checkpoint Role for SRP GTPase Activation
نویسندگان
چکیده
Co-translational protein targeting by the signal recognition particle (SRP) relies on a complex series of structural rearrangements in the SRP and its receptor (SR). In order to precisely coordinate the individual steps, the GTPases of the SRP and the SR form a unique complex in which GTP hydrolysis is activated in a composite active site. A recent study provides new insights on the link between the GTPases and protein translocation.
منابع مشابه
Conformational changes in the GTPase modules of the signal reception particle and its receptor drive initiation of protein translocation
During cotranslational protein targeting, two guanosine triphosphatase (GTPase) in the signal recognition particle (SRP) and its receptor (SR) form a unique complex in which hydrolyses of both guanosine triphosphates (GTP) are activated in a shared active site. It was thought that GTP hydrolysis drives the recycling of SRP and SR, but is not crucial for protein targeting. Here, we examined the ...
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عنوان ژورنال:
- Current Biology
دوره 17 شماره
صفحات -
تاریخ انتشار 2007