Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
PLoS Genet. 2012 Jan;8(1):e1002464. doi: 10.1371/journal.pgen.1002464. Epub 2012 Jan 19.
Secretion of neurotransmitters and neuropeptides is mediated by exocytosis of distinct secretory organelles, synaptic vesicles (SVs) and dense core vesicles (DCVs) respectively. Relatively little is known about factors that differentially regulate SV and DCV secretion. Here we identify a novel protein RIC-7 that is required for neuropeptide secretion in Caenorhabditis elegans. The RIC-7 protein is expressed in all neurons and is localized to presynaptic terminals. Imaging, electrophysiology, and behavioral analysis of ric-7 mutants indicates that acetylcholine release occurs normally, while neuropeptide release is significantly decreased. These results suggest that RIC-7 promotes DCV-mediated secretion.
神经递质和神经肽的分泌是由不同的分泌细胞器，突触小泡（SVs）和致密核心囊泡（DCVs）的胞吐作用介导的。相对而言，对于差异化调节 SV 和 DCV 分泌的因素知之甚少。在这里，我们鉴定了一种新型蛋白 RIC-7，它是秀丽隐杆线虫中神经肽分泌所必需的。RIC-7 蛋白在所有神经元中表达，并定位于突触前末端。ric-7 突变体的成像、电生理学和行为分析表明，乙酰胆碱释放正常，而神经肽释放显著减少。这些结果表明 RIC-7 促进了 DCV 介导的分泌。
