Autophagosome formation depends on the small GTPase Rab1 and functional ER exit sites
- PMID: 20545908
- DOI: 10.1111/j.1600-0854.2010.01086.x
Autophagosome formation depends on the small GTPase Rab1 and functional ER exit sites
Abstract
Autophagy is an important cellular degradation pathway present in all eukaryotic cells. Via this pathway, portions of the cytoplasm and/or organelles are sequestered in double-membrane structures called autophagosomes. In spite of the significant advance achieved in autophagy, the long-standing question about the source of the autophagic membrane remains unsolved. We have investigated the role of the secretory pathway in autophagosome biogenesis. Sar1 and Rab1b are monomeric GTPases that control traffic from the endoplasmic reticulum (ER) to the Golgi. We present evidence indicating that the activity of both proteins is required for autophagosome formation. Overexpression of dominant-negative mutants and the use of siRNAs impaired autophagosome generation as determined by LC3 puncta formation and light chain 3 (LC3)-II processing. In addition, our results indicate that the autophagic and secretory pathways intersect at a level preceding the brefeldin A blockage, suggesting that the transport from the cis/medial Golgi is not necessary for autophagosome biogenesis. Our present results highlight the role of transport from the ER in the initial events of the autophagic vacuole development.
Similar articles
-
Starvation triggers the delivery of the endoplasmic reticulum to the vacuole via autophagy in yeast.Traffic. 2005 Jan;6(1):56-65. doi: 10.1111/j.1600-0854.2004.00245.x. Traffic. 2005. PMID: 15569245
-
Traffic-independent function of the Sar1p/COPII machinery in proteasomal sorting of the cystic fibrosis transmembrane conductance regulator.J Cell Biol. 2003 Jan 20;160(2):157-63. doi: 10.1083/jcb.200210086. Epub 2003 Jan 21. J Cell Biol. 2003. PMID: 12538638 Free PMC article.
-
Live-cell imaging of Aspergillus nidulans autophagy: RAB1 dependence, Golgi independence and ER involvement.Autophagy. 2013 Jul;9(7):1024-43. doi: 10.4161/auto.24483. Epub 2013 Apr 8. Autophagy. 2013. PMID: 23722157 Free PMC article.
-
Mechanisms of COPII vesicle formation and protein sorting.FEBS Lett. 2007 May 22;581(11):2076-82. doi: 10.1016/j.febslet.2007.01.091. Epub 2007 Feb 14. FEBS Lett. 2007. PMID: 17316621 Review.
-
Autophagosome formation: core machinery and adaptations.Nat Cell Biol. 2007 Oct;9(10):1102-9. doi: 10.1038/ncb1007-1102. Nat Cell Biol. 2007. PMID: 17909521 Review.
Cited by
-
A dual role of ERGIC-localized Rabs in TMED10-mediated unconventional protein secretion.Nat Cell Biol. 2024 Jul;26(7):1077-1092. doi: 10.1038/s41556-024-01445-4. Epub 2024 Jun 26. Nat Cell Biol. 2024. PMID: 38926505
-
RICH1 is a novel key suppressor of isoproterenol‑ or angiotensin II‑induced cardiomyocyte hypertrophy.Mol Med Rep. 2024 May;29(5):69. doi: 10.3892/mmr.2024.13193. Epub 2024 Mar 8. Mol Med Rep. 2024. PMID: 38456539 Free PMC article.
-
Biochemical Structure and Function of TRAPP Complexes in the Cardiac System.JACC Basic Transl Sci. 2023 Jul 12;8(12):1599-1612. doi: 10.1016/j.jacbts.2023.03.011. eCollection 2023 Dec. JACC Basic Transl Sci. 2023. PMID: 38205348 Free PMC article.
-
TOR-mediated Ypt1 phosphorylation regulates autophagy initiation complex assembly.EMBO J. 2023 Oct 4;42(19):e112814. doi: 10.15252/embj.2022112814. Epub 2023 Aug 28. EMBO J. 2023. PMID: 37635626
-
Impact of interorganelle coordination between the conventional early secretory pathway and autophagy in cellular homeostasis and stress response.Front Cell Dev Biol. 2023 Apr 21;11:1069256. doi: 10.3389/fcell.2023.1069256. eCollection 2023. Front Cell Dev Biol. 2023. PMID: 37152281 Free PMC article. Review.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Other Literature Sources
Molecular Biology Databases