Topic: Proteomic Profiling of Transport Vesicles Reveals Insights into Cargo Sorting in the Secretory Pathway

Speaker: Yusong Guo, Associate Professor

Host：Cong Yu, Associate Professor

Time: 16:00-17:30; April 25, 2025

Venue: Lynn Library 111

Abstract:

Transport vesicles play a crucial role in secretory and endocytic trafficking, relying on precise cargo sorting and vesicle targeting. Yet, the machinery regulating these processes, especially for physiologically and clinically relevant cargoes, remains poorly understood. To address this gap, we developed an in vitro vesicle formation assay coupled with quantitative mass spectrometry to profile vesicle proteomes. In this talk, I will present our latest findings using this approach to investigate the sorting and surface delivery of two distinct cargoes: the planar cell polarity protein Frizzled6 and the large extracellular matrix component Collagen. Our results provide novel mechanistic insights into their biosynthetic trafficking, which is essential for their physiological functions. Furthermore, we demonstrate that this proteomic strategy is a powerful tool for identifying cargo-specific trafficking factors and uncovering novel regulators of vesicular transport.

Brief introduction of the speaker:

Dr. Yusong Guo is an Associate Professor (tenured) in the Division of Life Science at the Hong Kong University of Science and Technology (HKUST). He earned his PhD in Cell Biology from Carnegie Mellon University and conducted postdoctoral research in the laboratory of Nobel Laureate Prof. Randy Schekman at UC Berkeley. Since establishing his independent research group at HKUST in 2015, Dr. Guo has focused on elucidating the molecular mechanisms of cargo sorting in the secretory pathway. His lab combines biochemical reconstitution, quantitative proteomics, and cell biological approaches to study how transmembrane signaling receptors and soluble signaling molecules—particularly those linked to human diseases—are selectively packaged into transport vesicles. A key contribution of his group is the development of an innovative in vitro vesicle formation assay coupled with mass spectrometry, which has enabled the discovery of novel regulators of vesicular trafficking. Dr. Guo’s work has been recognized with prestigious awards, including the Early Career Award from the Hong Kong Research Grants Council and the Teaching Award from HKUST’s School of Science.