Min, Duyoung Kim, Kipom Hyeon, Changbong Cho, Yong Hoon Shin, Yeon-Kyun Yoon, Tae-Young 2024-01-20T12:33:48Z 2024-01-20T12:33:48Z 2021-09-01 2013-04 2041-1723 https://pubs.kist.re.kr/handle/201004/128217 Formation of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex provides mechanical thrust for membrane fusion, but its molecular mechanism is still unclear. Here using magnetic tweezers, we observe mechanical responses of a single neuronal SNARE complex under constant pulling force. Single SNARE complexes may be unzipped with 34 pN force. When rezipping is induced by lowering the force to 11 pN, only a partially assembled state results, with the C-terminal half of the SNARE complex remaining disassembled. Reassembly of the C-terminal half occurs only when the force is further lowered below 11 pN. Thus, mechanical hysteresis, characterized by the unzipping and rezipping cycle of a single SNARE complex, produces the partially assembled state. In this metastable state, unzipping toward the N-terminus is suppressed while zippering toward the C-terminus is initiated as a steep function of force. This ensures the directionality of SNARE-complex formation, making the SNARE complex a robust force-generating machine. English NATURE PUBLISHING GROUP MAGNETIC TWEEZERS VESICLE FUSION SYNAPTOBREVIN DNA MICROMANIPULATION SYNAPTOTAGMIN-1 DYNAMICS BINDING Mechanical unzipping and rezipping of a single SNARE complex reveals hysteresis as a force-generating mechanism Article 10.1038/ncomms2692 1 NATURE COMMUNICATIONS, v.4 NATURE COMMUNICATIONS 4 scie scopus 000318872100062 2-s2.0-84877779303 Multidisciplinary Sciences Science & Technology - Other Topics Article MAGNETIC TWEEZERS VESICLE FUSION SYNAPTOBREVIN DNA MICROMANIPULATION SYNAPTOTAGMIN-1 DYNAMICS BINDING Biological sciences Biophysics Cell biology