PICK1 is a multi-functional protein that participates in protein trafficking. While most of the studies focus on its roles in regulating protein trafficking during synaptic plasticity, increasing evidence suggests that it may also play important roles in the biogenesis of secretory granules (SGs), or dense core vesicles (DCVs). One of the evidences supporting this notion is the finding that PICK1 is associated with DCVs. The exact roles of PICK1 in DCV biogenesis, however, have not been fully elucidated. DCVs are one type of regulated secretory vesicles and their cargos are mainly bioactive peptides such as insulin. Since the turnover of DCVs consists of several steps including budding, maturation, trafficking and regulated exocytosis, we utilized the worms’ powerful genetics a...[ Read more ]

PICK1 is a multi-functional protein that participates in protein trafficking. While most of the studies focus on its roles in regulating protein trafficking during synaptic plasticity, increasing evidence suggests that it may also play important roles in the biogenesis of secretory granules (SGs), or dense core vesicles (DCVs). One of the evidences supporting this notion is the finding that PICK1 is associated with DCVs. The exact roles of PICK1 in DCV biogenesis, however, have not been fully elucidated. DCVs are one type of regulated secretory vesicles and their cargos are mainly bioactive peptides such as insulin. Since the turnover of DCVs consists of several steps including budding, maturation, trafficking and regulated exocytosis, we utilized the worms’ powerful genetics and easy drug assays to dissect worm PICK-1’s role in these processes. Interestingly, through the evaluation of performance of double mutant worms of pick-1 and other DCV-associated genes in acute aldicarb assay, PICK-1 was found to have dual functions that may be involved in both the maturation and controlled release of DCVs. Moreover, the relationships of pick-1 gene with other genes implicated in the maturation process of DCVs further support PICK-1’s function in this process.