Regulation of coat assembly--sorting things out at the ER.
The small GTPase Sar1 resides at the core of a regulatory cycle that controls protein export from the ER in COPII vesicles. Recent advances in minimally reconstituted systems indicate continual flux of Sar1 through GTPase cycles facilitates cargo concentration into forming vesicles that ultimately bud from membranes. During export from ER membranes, this GTPase cycle is harnessed through the combinatorial power of multiple coat subunits and cargo adaptors to sort an expanding array of proteins into ER-derived vesicles. The COPII budding machinery is further organized into higher-order structures at transitional zones on the ER surface where the large multi-domain Sec16 protein appears to perform a central function.
Miller
Elizabeth A
EA
Department of Biological Sciences, Columbia University, New York, NY 10027, USA. em2282@columbia.edu
Barlowe
Charles
C
D000818:Animals; D022181:COP-Coated Vesicles / Q000201:enzymology / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000201:enzymology / Q000378:metabolism*; D020558:GTP Phosphohydrolases / Q000378:metabolism; D006801:Humans; D008563:Membrane Lipids / Q000378:metabolism; D021381:Protein Transport; D033921:Vesicular Transport Proteins / Q000378:metabolism
D008563:Membrane Lipids; D033921:Vesicular Transport Proteins; D020558:GTP Phosphohydrolases