A role of MTC1 in membrane trafficking

Abstract

Membrane trafficking is an essential process for transporting materials in cells. It consists of a number of trafficking pathways interacting and regulating each other forming a sophisticated network. Despite it has been intensively studied for decades, there are still a lot of puzzles remained unsolved. In this study, we characterize the role of MTC1, which is a gene with unknown function and has been speculated being related to maintenance of telomere capping, for its involvement in the membrane trafficking processes, and provide evidence to show that it is involved in cis-Golgi associated trafficking In a previous suppressor screening study of a trafficking mutant, vps74 arginine mutant, our former lab member, miss Ping Yu, discovered that MTC1 is a mild temperature sensitivity (TS) suppressor of the mutant. From there, we hypothesized MTC1 may have a role in the membrane trafficking. To investigate its role, genetic interaction and cellular physiology experiments were conducted. The genetics study showed MTC1 is synthetic TS with four non-essential subunits of COG complex, specific subunit of TRAPPIII, SNARE SEC22, GET complex subunit GET3 and Golgi small GTPase YPT6, strongly indicating the involvement of Mtc1p in traffic processes. Cellular physiology studies showed that Gas1 and CPY maturations are defective in those TS double mutants, suggesting the role of Mtc1p is associated with Golgi apparatus. Finally, localization studies show that Mtc1p localizes to the early Golgi compartment, but the late Golgi, further narrowing down the role of Mtc1p to cis-Golgi associated trafficking.

Date of Award	2017
Original language	English
Awarding Institution	The Hong Kong University of Science and Technology