MSL Seminar Series: April – Invited Speaker, Dr. Liwen Jiang

Invited Speaker:

Dr. Liwen Jiang

Professor, School of Life Sciences, The Chinese University of Hong Kong

Host: Dr. Xin Li

This seminar will be presented in a hybrid format. Audience members are welcome to attend either in person at the MSL lecture theatre (room 102) or via the zoom link. Those connecting via zoom will be able to ask questions during the Q&A portion using the chat function.

Zoom registration link: https://ubc.zoom.us/meeting/register/o5IcrJcjSWuck7ySi7VvaQ

Talk title: Organelle Biogenesis and Function in Plants

Abstract:

Membrane trafficking and organelle biogenesis play important roles in regulating plant growth and development, as well as responses to external signals. The plant endomembrane system contains several functionally distinct membrane-enclosed organelles, including the endoplasmic reticulum (ER), Golgi apparatus, trans-Golgi network (TGN)/early endosomes (EE), prevacuolar compartment (PVC)/multivesicular body (MVB)/late endosome (LE)/ and vacuole. The endosomal sorting complex required for transport (ESCRT) machinery mediates the formation of intraluminal vesicles (ILVs) in MVBs as well as the sorting of the ubiquitinated cargoes into MVBs for subsequent vacuolar delivery and degradation in eukaryotes. Since 2014, we have characterized a plant unique ESCRT component termed FYVE domain protein required for endosomal sorting 1 (FREE1) and demonstrated that FREE1 plays multiple functions with distinct underlying mechanisms in plants, including regulation of MVB and vacuole formation (Current Biology 2014; Nature Plants 2019, Nature 2024), Abscisic Acid (ABA) signaling (Nature Plants 2019; 2021), crosstalk between the endomembrane system and the autophagic pathway (PNAS 2015), degradation of lipid droplets (LDs) in germinating seedlings (Plant Cell 2022), and autophagosome closure under stress condition (Nature Communications 2023). We have also identified and characterized several Arabidopsis suppressors of free1 (sof) as novel regulators of the MVB pathway (Nature Communications 2018; Plant Cell 2019; Plant Cell 2023). In addition to the MVB, we have also developed whole-cell electron tomography (ET) models of vacuole biogenesis in various plant cell types (Nature Plants 2019; Plant Physiology 2022; Plant Cell 2025), and more recently, a cryo-ET model of vacuole fission in Arabidopsis developing pollens (Liang et al., 2025). Supported by Research Grants Council (RGC) of Hong Kong and CUHK.