Trafficking and Activity Dependent Function of Vesicular Transporters

摘要: Vesicular neurotransmitter transporters (VNTs) are a small family of proteins responsible for packaging into secretory vesicles. Their presence and function required regulated secretion from neuronal neuroendocrine cells. During both the biogenesis activity-dependent recycling vesicles, VNTs undergo trafficking that can determine quality, quantity, location packaged neurotransmitter. Thus understanding signals mechanisms VNT is essential to regulation neurotransmission. Here, synaptic vesicle specific Acetylcholine Transporter (VAChT) investigated. A dileucine containing targeting motif, with dual properties internalization targeting, identified in C-terminus VAChT. Chimeras between this motif an unrelated plasma membrane protein localize synaptic-vesicle-like vesicles cell line. The specificity generalization assessed. Next, sorting nexin 5 (SNX5), implicated traffic, as novel regulator VAChT Disruption SNX5 leads decrease VAChT-directed concomitant increase large dense core This shift granules suggests important mechanism potential shape In order understand physiologic importance regulation, vesicular transport its influence on release must be assessed living neurons. However, has not been possible. Therefore, live assay was established measure contributions brain slice. Using pH sensitive, fluorescent serotonin analog visualized by two-photon microscopy, activity dependent somatic monoamine transporter (VMAT) were measured dorsal raphe nucleus. Interestingly, while portion at rest held reserve, during stimulation released efficiently. work presented thesis provides greater function. Furthermore, it foundation comprehensive study active role shaping