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Updated: Apr 23, 2026

Study of Protein-protein Interactions in Autophagy Research
14:08

Study of Protein-protein Interactions in Autophagy Research

Published on: September 9, 2017

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Hrr25 triggers selective autophagy-related pathways by phosphorylating receptor proteins

Chikara Tanaka1, Li-Jing Tan1, Keisuke Mochida1

  • 1Frontier Research Center and Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Midori-ku, Yokohama 226-8503, Japan.

The Journal of Cell Biology
|October 8, 2014
PubMed

Insights

The Hrr25 kinase regulates selective autophagy by phosphorylating receptors Atg19 and Atg36. This enhances their interaction with Atg11, a key component in autophagosome formation for degrading cellular targets.

Area of Science:

  • Cellular Biology
  • Molecular Biology
  • Biochemistry

Background:

  • Selective autophagy precisely targets cellular components for degradation via the lysosome or vacuole.
  • While target recognition mechanisms are known, the regulatory processes governing selective autophagy remain largely unelucidated.

Purpose of the Study:

  • To investigate the role of the conserved kinase Hrr25 in regulating selective autophagy pathways.
  • To identify specific substrates and mechanisms through which Hrr25 influences autophagy.

Main Methods:

  • Utilized Saccharomyces cerevisiae as a model organism.
  • Investigated the phosphorylation status of autophagy receptor proteins (Atg19, Atg36) by Hrr25.
  • Assessed the impact of Hrr25-mediated phosphorylation on receptor-adaptor interactions (with Atg11).

Main Results:

  • Hrr25 phosphorylates Atg19 in the cytoplasm-to-vacuole targeting pathway and Atg36 in pexophagy.
  • Hrr25-dependent phosphorylation strengthens the binding of Atg19 and Atg36 to the adaptor protein Atg11.
  • This interaction facilitates the recruitment of core autophagy machinery for autophagosome formation.

Conclusions:

  • Hrr25 is a novel regulator of selective autophagy in yeast.
  • A conserved mechanism involving phosphoregulation of receptor-adaptor interactions governs distinct selective autophagy pathways.

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