» Articles » PMID: 11149932

The Sar1 GTPase Coordinates Biosynthetic Cargo Selection with Endoplasmic Reticulum Export Site Assembly

Overview
Journal J Cell Biol
Specialty Cell Biology
Date 2001 Jan 10
PMID 11149932
Citations 98
Authors
Affiliations
Soon will be listed here.
Abstract

Cargo selection and export from the endoplasmic reticulum is mediated by the COPII coat machinery that includes the small GTPase Sar1 and the Sec23/24 and Sec13/31 complexes. We have analyzed the sequential events regulated by purified Sar1 and COPII coat complexes during synchronized export of cargo from the ER in vitro. We find that activation of Sar1 alone, in the absence of other cytosolic components, leads to the formation of ER-derived tubular domains that resemble ER transitional elements that initiate cargo selection. These Sar1-generated tubular domains were shown to be transient, functional intermediates in ER to Golgi transport in vitro. By following cargo export in live cells, we show that ER export in vivo is also characterized by the formation of dynamic tubular structures. Our results demonstrate an unanticipated and novel role for Sar1 in linking cargo selection with ER morphogenesis through the generation of transitional tubular ER export sites.

Citing Articles

The proximity interactome of PML isoforms I and II under fatty acid stress.

Thompson J, Boisvert F, Salsman J, Levesque D, Dellaire G, Ridgway N FEBS Lett. 2024; 599(5):682-699.

PMID: 39703998 PMC: 11891419. DOI: 10.1002/1873-3468.15081.


Small GTPase ActIvitY ANalyzing (SAIYAN) system: A method to detect GTPase activation in living cells.

Maeda M, Arakawa M, Komatsu Y, Saito K J Cell Biol. 2024; 223(10).

PMID: 39101946 PMC: 11303508. DOI: 10.1083/jcb.202403179.


COPII cage assembly factor Sec13 integrates information flow regulating endomembrane function in response to human variation.

Angles F, Gupta V, Wang C, Balch W Sci Rep. 2024; 14(1):10160.

PMID: 38698045 PMC: 11065896. DOI: 10.1038/s41598-024-60687-2.


Nutrient deprivation alters the rate of COPII subunit recruitment at ER subdomains to tune secretory protein transport.

Kasberg W, Luong P, Swift K, Audhya A Nat Commun. 2023; 14(1):8140.

PMID: 38066006 PMC: 10709328. DOI: 10.1038/s41467-023-44002-7.


The Sar1 GTPase is dispensable for COPII-dependent cargo export from the ER.

Kasberg W, Luong P, Hanna M, Minushkin K, Tsao A, Shankar R Cell Rep. 2023; 42(6):112635.

PMID: 37300835 PMC: 10592460. DOI: 10.1016/j.celrep.2023.112635.


References
1.
Nishimura N, Balch W . A di-acidic signal required for selective export from the endoplasmic reticulum. Science. 1997; 277(5325):556-8. DOI: 10.1126/science.277.5325.556. View

2.
Rowe T, Balch W . Expression and purification of mammalian Sarl. Methods Enzymol. 1995; 257:49-53. DOI: 10.1016/s0076-6879(95)57009-8. View

3.
Aniento F, Emans N, Griffiths G, Gruenberg J . Cytoplasmic dynein-dependent vesicular transport from early to late endosomes. J Cell Biol. 1993; 123(6 Pt 1):1373-87. PMC: 2290907. DOI: 10.1083/jcb.123.6.1373. View

4.
Sevier C, Weisz O, Davis M, Machamer C . Efficient export of the vesicular stomatitis virus G protein from the endoplasmic reticulum requires a signal in the cytoplasmic tail that includes both tyrosine-based and di-acidic motifs. Mol Biol Cell. 2000; 11(1):13-22. PMC: 14753. DOI: 10.1091/mbc.11.1.13. View

5.
Scales S, Pepperkok R, Kreis T . Visualization of ER-to-Golgi transport in living cells reveals a sequential mode of action for COPII and COPI. Cell. 1997; 90(6):1137-48. DOI: 10.1016/s0092-8674(00)80379-7. View