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Applications of pHluorin for Quantitative, Kinetic and High-throughput Analysis of Endocytosis in Budding Yeast
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Nbr1, a Receptor for ESCRT-Dependent Endosomal Microautophagy in Fission Yeast

Noboru Mizushima1

  • 1Department of Biochemistry and Molecular Biology, Graduate School and Faculty of Medicine, The University of Tokyo, Tokyo 113-0033, Japan.

Molecular Cell
|September 20, 2015
PubMed

Insights

Fission yeast Nbr1 functions as a receptor in endosomal microautophagy. This process delivers cytosolic hydrolytic enzymes to the vacuole via the ESCRT pathway.

Area of Science:

  • Cell Biology
  • Molecular Biology
  • Autophagy Research

Background:

  • Macroautophagy receptors play crucial roles in cellular degradation pathways.
  • Endosomal microautophagy is a specialized form of autophagy involving the vacuole/lysosome.
  • The ESCRT machinery is involved in membrane trafficking and vesicle formation.

Purpose of the Study:

  • To investigate the role of fission yeast Nbr1 in autophagy.
  • To identify novel receptors involved in endosomal microautophagy.
  • To elucidate the mechanism of substrate delivery to the vacuole via ESCRT-dependent pathways.

Main Methods:

  • Utilized fission yeast as a model organism.
  • Investigated protein homology between yeast and mammalian NBR1.
  • Employed techniques to study protein localization and function in autophagy and ESCRT pathways.

Main Results:

  • Fission yeast Nbr1 shares partial homology with mammalian NBR1.
  • Nbr1 acts as a receptor for ESCRT-dependent endosomal microautophagy.
  • This pathway facilitates the delivery of two specific hydrolytic enzymes from the cytosol to the vacuole.

Conclusions:

  • Nbr1 is a key receptor mediating endosomal microautophagy in fission yeast.
  • This finding reveals a conserved role for NBR1 in selective autophagy.
  • The study highlights the involvement of the ESCRT pathway in delivering cytosolic components to the vacuole.

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