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Updated: Mar 12, 2026
08:44
Isolating Potentiated Hsp104 Variants Using Yeast Proteinopathy Models
Published on: November 11, 2014
8.5K
Hsv2, a yeast PROPPIN, drives bulk and selective microautophagy
Kohtaro Yasumori1, Takashi Ushimaru2
1Graduate School of Science and Technology, Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, 422-8021, Japan.
Biochemical and Biophysical Research Communications
|March 10, 2026
Summary
The study reveals Hsv2
Area of Science:
- Autophagy research
- Cellular biology
- Molecular mechanisms of membrane trafficking
Background:
- Polyphosphoinositide-binding proteins (PROPPINs) are crucial for autophagy.
- Hsv2 is a less-characterized PROPPIN in yeast autophagy.
- The specific role of Hsv2 in autophagy remains unclear.
Purpose of the Study:
- To elucidate the function of Hsv2 in yeast autophagy.
- To investigate the role of Hsv2 in microautophagy and micronucleophagy.
- To understand the molecular mechanisms underlying Hsv2-mediated membrane remodeling.
Main Methods:
- Genetic analysis of Hsv2 deletion mutants.
- Fluorescence microscopy to track protein localization (GFP-Pho8, Nop1-GFP).
- Analysis of protein colocalization with ESCRT components and Atg2.
Main Results:
- Hsv2 is essential for rapamycin-induced bulk microautophagy and micronucleophagy.
- Hsv2 localization to the vacuolar membrane depends on its amphipathic helix.
- Hsv2 functions with Atg2 to promote lipid transfer for membrane invagination.
Conclusions:
- Hsv2 plays a critical role in specific microautophagy pathways.
- The Hsv2-Atg2 complex facilitates lipid supply to ESCRT-dependent membrane deformation.
- This complex is vital for efficient substrate engulfment during autophagy.
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