title: GABARAPL1 (GEC1) associates with autophagic vesicles.
abstract: Gabarapl1 (gec1) was first described as an estrogen regulated gene which shares a high sequence homology with the gabarap gene. We previously demonstrated that GABARAPL1, like GABARAP, interacts with the GABAA receptor and tubulin and promotes tubulin polymerization. Previous work has demonstrated that the GABARAP family members (GABARAP, LC3, GATE-16 and Atg8) are not only involved in the transport of proteins or vesicles but are also implicated in various mechanisms such as autophagy, cell death, cell proliferation and tumor progression. We therefore asked whether GABARAPL1 might also play a role in autophagy. First, we showed that GABARAPL1 is cleaved at glycine 116, a residue which is conserved in other members of the family. We also demonstrated that GABARAPL1 is linked to phospholipids, delipidated by Atg4B, associated with intracellular membranes and accumulated in intracellular vesicles after inhibition of lysosomal activity. Finally, we showed that GABARAPL1 partially colocalizes with LC3 or Lysotracker green in intracellular vesicles. Taken together, our results demonstrate that GABARAPL1 associates with autophagic vesicles.
authors.affiliation: Université de Franche-Comté, Laboratoire de Biochimie, EA3922, Estrogènes, Expression Génique et Pathologies du Système Nerveux Central, IFR133, U.F.R. Sciences et Techniques, Besançon, France.
authors.forename: Fatima Zahra
authors.initials: FZ
authors.lastname: Chakrama
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Seguin-Py
authors.forename: Jaclyn Nicole
authors.initials: JN
authors.lastname: Le Grand
authors.forename: Annick
authors.initials: A
authors.lastname: Fraichard
authors.forename: Régis
authors.initials: R
authors.lastname: Delage-Mourroux
authors.forename: Gilles
authors.initials: G
authors.lastname: Despouy
authors.forename: Valérie
authors.initials: V
authors.lastname: Perez
authors.forename: Michèle
authors.initials: M
authors.lastname: Jouvenot
authors.forename: Michaël
authors.initials: M
authors.lastname: Boyer-Guittaut
mesh_terms: D000588:Amines / Q000378:metabolism; D000818:Animals; D001343:Autophagy; D000071187:Autophagy-Related Protein 5; D000071183:Autophagy-Related Proteins; D002462:Cell Membrane / Q000378:metabolism; D003546:Cysteine Endopeptidases / Q000378:metabolism; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D004622:Embryo, Mammalian / Q000166:cytology; D005347:Fibroblasts / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D042541:Intracellular Space / Q000378:metabolism; D008247:Lysosomes / Q000378:metabolism; D061986:MCF-7 Cells; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000172:deficiency / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D021381:Protein Transport; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D013194:Staining and Labeling
chemical_list: D000588:Amines; C495773:Atg5 protein, mouse; D000071187:Autophagy-Related Protein 5; D000071183:Autophagy-Related Proteins; C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D010743:Phospholipids; D011993:Recombinant Fusion Proteins; C493330:Red DND-99; D049452:Green Fluorescent Proteins; C507524:ATG4B protein, human; D003546:Cysteine Endopeptidases; D005998:Glycine