Ch'ng Queelim, Sieburth Derek, Kaplan Joshua M
Department of Molecular Biology, Massachusetts General Hospital, Boston, Massachusetts, United States of America.
PLoS Genet. 2008 Nov;4(11):e1000283. doi: 10.1371/journal.pgen.1000283. Epub 2008 Nov 28.
Cells are organized into distinct compartments to perform specific tasks with spatial precision. In neurons, presynaptic specializations are biochemically complex subcellular structures dedicated to neurotransmitter secretion. Activity-dependent changes in the abundance of presynaptic proteins are thought to endow synapses with different functional states; however, relatively little is known about the rules that govern changes in the composition of presynaptic terminals. We describe a genetic strategy to systematically analyze protein localization at Caenorhabditis elegans presynaptic specializations. Nine presynaptic proteins were GFP-tagged, allowing visualization of multiple presynaptic structures. Changes in the distribution and abundance of these proteins were quantified in 25 mutants that alter different aspects of neurotransmission. Global analysis of these data identified novel relationships between particular presynaptic components and provides a new method to compare gene functions by identifying shared protein localization phenotypes. Using this strategy, we identified several genes that regulate secretion of insulin-like growth factors (IGFs) and influence lifespan in a manner dependent on insulin/IGF signaling.
细胞被组织成不同的区室，以便在空间上精确地执行特定任务。在神经元中，突触前特化是致力于神经递质分泌的生物化学复杂的亚细胞结构。突触前蛋白丰度的活性依赖性变化被认为赋予突触不同的功能状态；然而，关于支配突触前终末组成变化的规则，我们所知相对较少。我们描述了一种遗传策略，用于系统地分析秀丽隐杆线虫突触前特化处的蛋白质定位。九种突触前蛋白被绿色荧光蛋白（GFP）标记，从而能够可视化多个突触前结构。在改变神经传递不同方面的25个突变体中，对这些蛋白质的分布和丰度变化进行了定量分析。对这些数据的全局分析确定了特定突触前成分之间的新关系，并提供了一种通过识别共享的蛋白质定位表型来比较基因功能的新方法。使用这种策略，我们鉴定了几个调节胰岛素样生长因子（IGF）分泌并以依赖胰岛素/IGF信号传导的方式影响寿命的基因。
