Cellular dynamics of functional molecules and second messengers during synaptic transmission

点击翻译按钮获取中文摘要

The inositol high-polyphodphate series (IP4, IP5 and IP6 ; IHPS) inhibit the neurotransmission through binding to the 2nd C2 domain of synaptotagmin (Syt), synaptic vesicle membrane proteins using superior cervical ganglion and squid giant synapse. Now we have revealed several proteins, including alpha adaptins which are specific subunits of clathrin AP2, from mouse brain were eluted by affinity elution chromatography from the C2 domain of Syt II-immobilized Sepharose using 50muM of inositol hexakisphosphate (IP6). The interaction between Syt II and AP2 was inhibited more strongly by IHPS than by the same concentration of IP3. Limited digestion of mouse crude synaptosomal fractions with trypsin revealed different cleavage pattern between in the presenc and the absence of 50muM IP6. These results suggests that IHPS-binding to C2B domain of synaptotagmin alter the state of protein-protein interaction such as synaptotagmin-AP2 interaction, which may induce the inhibition of some events involved in the neurotransmission, e.g. endocytosis.