Comobility of GABARAP and Phosphatidylinositol 4-Kinase 2A on Cytoplasmic Vesicles

Yan Chen, Hui Qiao Sun, John P. Eichorst, Joseph P. Albanesi, Helen Yin, Joachim D. Mueller

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We previously reported that recruitment of the type IIA phosphatidylinositol 4-kinase (PI4K2A) to autophagosomes by GABARAP, a member of the Atg8 family of autophagy-related proteins, is important for autophagosome-lysosome fusion. Because both PI4K2A and GABARAP have also been implicated in the intracellular trafficking of plasma membrane receptors in the secretory/endocytic pathway, we characterized their interaction in cells under nonautophagic conditions. Fluorescence fluctuation spectroscopy measurements revealed that GABARAP exists predominantly as a cytosolic monomer in live cells, but is recruited to small cytoplasmic vesicles upon overexpression of PI4K2A. C-Terminal lipidation of GABARAP, which is essential for its autophagic activities, is not necessary for its recruitment to these PI4K2A-containing transport vesicles. However, a GABARAP truncation mutant lacking C-terminal residues 103-117 fails to bind to PI4K2A, is not recruited to cytoplasmic vesicles, and does not codistribute with PI4K2A on subcellular organelles. These observations suggest that the PI4K2A-GABARAP interaction plays a role in membrane trafficking both under autophagic and nonautophagic conditions.

Original languageEnglish (US)
Pages (from-to)3556-3559
Number of pages4
JournalBiochemistry
Volume57
Issue number26
DOIs
StatePublished - Jul 3 2018

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Cytoplasmic Vesicles
1-Phosphatidylinositol 4-Kinase
Cell membranes
Fusion reactions
Monomers
Fluorescence
Spectroscopy
Membranes
Transport Vesicles
Secretory Pathway
Fluorescence Spectrometry
Lysosomes
Cell Communication
Organelles
Proteins
Cell Membrane
Autophagosomes
Autophagy-Related Proteins

ASJC Scopus subject areas

  • Biochemistry

Cite this

Comobility of GABARAP and Phosphatidylinositol 4-Kinase 2A on Cytoplasmic Vesicles. / Chen, Yan; Sun, Hui Qiao; Eichorst, John P.; Albanesi, Joseph P.; Yin, Helen; Mueller, Joachim D.

In: Biochemistry, Vol. 57, No. 26, 03.07.2018, p. 3556-3559.

Research output: Contribution to journalArticle

Chen, Yan ; Sun, Hui Qiao ; Eichorst, John P. ; Albanesi, Joseph P. ; Yin, Helen ; Mueller, Joachim D. / Comobility of GABARAP and Phosphatidylinositol 4-Kinase 2A on Cytoplasmic Vesicles. In: Biochemistry. 2018 ; Vol. 57, No. 26. pp. 3556-3559.
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