세미나 Seminars

Extra Form
초청강사 Tae-Young Yoon
소속 Center for Nanomedicine, Institute for Basic Science (IBS), Yonsei University, Seoul, South Korea
일시 2016년 9월 29일(목) 오후5시
장소 아산이학관 331

“Observation of Single Membrane Proteins

under Mechanical Tension”

 

Single-molecule methods, which handle and monitor molecules one at a time, have been a powerful toolkit for elucidating molecular mechanisms underlying many fundamental biological processes. I will talk about two recent efforts made in our lab, where we endeavor to apply single-molecule methods to a special class of proteins, that is, membrane proteins. First, by applying pN-scale force to a single SNARE complex, a main force-generating machine for membrane fusion in all eukaryotes, we reveal large hysteresis in a mechanical unizipping and rezipping cycle of the SNARE complex. With combined application of different single-molecule methods, we show how this rigid SNARE complex is efficiently disassembled by NSF and SNAP. We observed that NSF exploits a spring-loaded mechanism to tightly couple its ATP hydrolysis with unfolding of the SNARE complex. Second, by employing single-molecule fluorescence imaging as the detection scheme, my lab is developing a single-molecule version of the co-immunoprecipitation (co-IP) analysis. Harnessing its single-molecule sensitivity and millisecond time resolution, we quantitatively determine protein-protein interactions and their relevant changes in given cells or tissues. This novel capability will shed light onto the molecular lesions that drive individual cancers at the protein-protein interaction level, where signal transduction physically occurs. I will close the talk with brief outlook for future researches.


20160929_세미나_Prof. Tae-Young Yoon.hwp