The juxtamembrane region of synaptotagmin 1 interacts with dynamin 1 and regulates vesicle fission during compensatory endocytosis in endocrine cells
JOURNAL OF CELL SCIENCE
Authors: McAdam, Robyn L.; Varga, Kelly T.; Jiang, Zhongjiao; Young, Fiona B.; Blandford, Vanessa; McPherson, Peter S.; Gong, Liang-Wei; Sossin, Wayne S.
Abstract
Synaptotagmin 1 (Syt1) is a synaptic vesicle protein that is important for the kinetics of both exocytosis and endocytosis, and is thus a candidate molecule to link these two processes. Although the tandem Ca2+-binding C2 domains of Syt1 have important roles in exocytosis and endocytosis, the function of the conserved juxtamembrane (jxm) linker region has yet to be determined. We now demonstrate that the jxm region of Syt1 interacts directly with the pleckstrin homology (PH) domain of the endocytic protein dynamin 1. By using cell-attached capacitance recordings with millisecond time resolution to monitor clathrin-mediated endocytosis of single vesicles in neuroendocrine chromaffin cells, we find that loss of this interaction prolongs the lifetime of the fission pore leading to defects in the dynamics of vesicle fission. These results indicate a previously undescribed interaction between two major regulatory proteins in the secretory vesicle cycle and that this interaction regulates endocytosis.
Association between cognitive performance and SYT1-rs2251214 among women with cocaine use disorder
JOURNAL OF NEURAL TRANSMISSION
Authors: Viola, Thiago Wendt; Schuch, Jaqueline Bohrer; Rovaris, Diego Luiz; Genovese, Rafael; Tondo, Lucca; Sanvicente-Vieira, Breno; Zaparte, Aline; Cupertino, Renata Basso; da Silva, Bruna Santos; Dotto Bau, Claiton Henrique; Grassi-Oliveira, Rodrigo
Abstract
The SNP rs2251214 of the SYT1 gene was recently associated with externalizing phenotypes, including ADHD and cocaine use disorder (CUD). Here, we investigated whether SYT1-rs2251214 could also be implicated with cognitive performance variations among women with CUD. Results showed that G homozygous (n = 146) have lower cognitive performance in the Stroop, Trail Making and Matrix Reasoning tests compared with A-allele carriers (n = 64), suggesting that rs2251214 may influence the severity of cognitive impairments in CUD.