FBS Colloquia No.340Laboratory of Intracellular Membrane Dynamics
| Seminar or Lecture |
Analysis of ER tethering factors required for organelle selective autophagy Haruki Tanabe [Graduate Student (D5/D5), Graduate School of Frontier Biosciences] Mechanism of Golgi degradation by autophagy Shinri Kitta [6th year student, Faculty of Medicine] |
|---|---|
| Date and Time | 31 Oct. 2023 (Tue), 12:15～13:00 |
| Place | 2F Seminar Room, BioSystems Building |
| Language | Japanese |
| Contact |
Satoshi Minami (Specially Appointed Assistant Professor) |
Analysis of ER tethering factors required for organelle selective autophagy
Cellular stresses such as nutrient starvation and organelle damage induce autophagy. In autophagy, doubled membrane structures called autophagosomes engulf cytoplasmic components and transport them to lysosomes for degradation. In mammalian cells, autophagosome formation occurs on specialized ER subdomains, suggesting that ER-associated factors are involved in autophagosome formation. To explore autophagy-related factors in the ER, we performed MS/MS analysis and identified ER tethering proteins involved in organelle contacts. These ER tethering factors are required for organelle-selective autophagy but not for bulk autophagy. In this seminar, I will present the role of the ER tethering factors in selective autophagy.
Mechanism of Golgi degradation by autophagy
Autophagy is a fundamental process for degrading and recycling cytosolic components. Autophagy non-selectively surrounds and degrades cytoplasmic components, but it can also selectively degrade specific organelles and proteins via autophagy receptors. Screening of autophagy-related factors in our laboratory identified YIPF3/YIPF4, a Golgi membrane protein with no known function, as a candidate factor. Since this factor has a characteristic sequence (LIR motif) required for autophagy receptors, it may act as a receptor for Golgi selective autophagy called Golgiphagy. In our analysis, we found that YIPF3 binds to the autophagy protein ATG8s in an LIR motif-dependent manner and that these factors are required for autophagy-induced Golgi degradation. In this talk, I will introduce the role of YIPF3/YIPF4 in selective autophagy.
