Functional role of syntaxin 1B in the regulation of synaptic vesicle exocytosis and of the readily releasable pool at central synapses

2014 Fiscal Year Final Research Report

• Project/Area Number: 24500462
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Neurophysiology and muscle physiology
• Research Institution: Kyorin University
• Principal Investigator: MISHIMA Tatsuya 杏林大学, 医学部, 助教 (40317095)
• Co-Investigator(Renkei-kenkyūsha): FUJIWARA Tomonori 杏林大学, 医学部, 准教授 (90255399)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: syntaxin1 / SNARE / シナプス伝達

Outline of Final Research Achievements

In this study, to examine the physiological function of STX1B, we analyzed the presynaptic properties of glutamatergic and GABAergic synapses in STX1B null mutant and STX1A/1B double null mutant mice. We found that the frequency of spontaneous quantal release was lower and the paired-pulse ratio of evoked postsynaptic currents was significantly greater in glutamatergic and GABAergic synapses of STX1B null neurons. Deletion of STX1B also accelerated synaptic vesicle turnover in glutamatergic synapses and decreased the size of the readily releasable pool in glutamatergic and GABAergic synapses. Moreover, STX1A/1B double null neurons showed reduced and asynchronous evoked synaptic vesicle release in glutamatergic and GABAergic synapses. Our results suggest that although STX1A and 1B share a basic function as neuronal t-SNAREs, STX1B but not STX1A is necessary for the regulation of spontaneous and evoked synaptic vesicle exocytosis in fast transmission.

Free Research Field

神経科学