Regulatory Factors for the Formation of the Complex of Rab3A and Ca^2+/Calmodulin = Calmodulin-Rab3A 복합체의 형성을 조절하는 조절인자에 관한 연구

다국어 초록 (Multilingual Abstract)

The GTPase Rab3A, one of small GTP-biding proteins, has been suggested to recycle on and off synaptic membranes and regulate the synaptic membrane docking and fusion with presynaptic plasma membrane in nerve terminal. RabGDI has been known to dissociate Rab3A from synaptic membranes, when the Rab3A contains GDP. Recently, it has been reported that Ca^2+/calmodulin also can cause Rab3A to dissociate from synaptic membranes in vitro. It is possible that the process of the Rab3A dissociation may be regulated by some factors. We studied which factor regulates the process of the dissociation of Rab3A induced by Ca^2+/calmodulin. Dissociation of Rab3A of the synaptic membranes with eliminated cytoplasmic domain of synaptobrevin by botulinum toxin was identical to that of membranes with intact synaptobrevin. However, the dissociation of Rab3A of synaptic membranes with degraded cytoplasmic domain of synaptophysin by collagenased slightly, suggesting that synaptophysin has a effect on the dissociation of Rab3A by Ca^2+/calmodulin. Rab3A of synaptic membranes preincubated with Ca^2+ could not dissociate from membranes. However, preincubation of synaptic membranes with GDPβS and Ca^2+ did not decrease the dissociation of Rab3A by Ca^2+/calmodulin. It suggests that another factor for regulating the dissociation of Rab3A by Ca^2+/calmodulin may be guanine nucleotide hydrolysase.

목차 (Table of Contents)

• Abstract
• Introduction
• Materials and Methods
• Results
• Discussion
• References