Phosphorylation of Atg31 is required for autophagy.
10.1007/s13238-015-0138-4
- Author:
Wenzhi FENG
1
;
Tong WU
;
Xiaoyu DAN
;
Yuling CHEN
;
Lin LI
;
She CHEN
;
Di MIAO
;
Haiteng DENG
;
Xinqi GONG
;
Li YU
Author Information
1. PTN Program, College of Life Science, Peking University, Beijing, 100871, China.
- Publication Type:Journal Article
- MeSH:
Alanine;
chemistry;
metabolism;
Amino Acid Motifs;
Aspartic Acid;
chemistry;
metabolism;
Autophagy;
genetics;
Autophagy-Related Proteins;
Carrier Proteins;
chemistry;
metabolism;
Gene Expression Regulation, Fungal;
Membrane Proteins;
chemistry;
metabolism;
Models, Molecular;
Molecular Sequence Data;
Nitrogen;
deficiency;
Phagosomes;
chemistry;
drug effects;
metabolism;
Phosphorylation;
Protein Transport;
Saccharomyces cerevisiae;
drug effects;
genetics;
metabolism;
Saccharomyces cerevisiae Proteins;
chemistry;
genetics;
metabolism;
Serine;
chemistry;
metabolism;
Signal Transduction;
Sirolimus;
pharmacology
- From:
Protein & Cell
2015;6(4):288-296
- CountryChina
- Language:English
-
Abstract:
Autophagy is an evolutionarily conserved cellular process which degrades intracellular contents. The Atg17-Atg31-Atg29 complex plays a key role in autophagy induction by various stimuli. In yeast, autophagy occurs with autophagosome formation at a special site near the vacuole named the pre-autophagosomal structure (PAS). The Atg17-Atg31-Atg29 complex forms a scaffold for PAS organization, and recruits other autophagy-related (Atg) proteins to the PAS. Here, we show that Atg31 is a phosphorylated protein. The phosphorylation sites on Atg31 were identified by mass spectrometry. Analysis of mutants in which the phosphorylated amino acids were replaced by alanine, either individually or in various combinations, identified S174 as the functional phosphorylation site. An S174A mutant showed a similar degree of autophagy impairment as an Atg31 deletion mutant. S174 phosphorylation is required for autophagy induced by various autophagy stimuli such as nitrogen starvation and rapamycin treatment. Mass spectrometry analysis showed that S174 is phosphorylated constitutively, and expression of a phosphorylation-mimic mutant (S174D) in the Atg31 deletion strain restores autophagy. In the S174A mutant, Atg9-positive vesicles accumulate at the PAS. Thus, S174 phosphorylation is required for formation of autophagosomes, possibly by facilitating the recycling of Atg9 from the PAS. Our data demonstrate the role of phosphorylation of Atg31 in autophagy.
