First Author | Shin OH | Year | 2003 |
Journal | Neuron | Volume | 37 |
Issue | 1 | Pages | 99-108 |
PubMed ID | 12526776 | Mgi Jnum | J:89486 |
Mgi Id | MGI:3040539 | Doi | 10.1016/s0896-6273(02)01145-5 |
Citation | Shin OH, et al. (2003) Sr2+ binding to the Ca2+ binding site of the synaptotagmin 1 C2B domain triggers fast exocytosis without stimulating SNARE interactions. Neuron 37(1):99-108 |
abstractText | Sr(2+) triggers neurotransmitter release similar to Ca(2+), but less efficiently. We now show that in synaptotagmin 1 knockout mice, the fast component of both Ca(2+)- and Sr(2+)-induced release is selectively impaired, suggesting that both cations partly act by binding to synaptotagmin 1. Both the C(2)A and the C(2)B domain of synaptotagmin 1 bind Ca(2+) in phospholipid complexes, but only the C(2)B domain forms Sr(2+)/phospholipid complexes; therefore, Sr(2+) binding to the C(2)B domain is sufficient to trigger fast release, although with decreased efficacy. Ca(2+) induces binding of the synaptotagmin C(2) domains to SNARE proteins, whereas Sr(2+) even at high concentrations does not. Thus, triggering of the fast component of release by Sr(2+) as a Ca(2+) agonist involves the formation of synaptotagmin/phospholipid complexes, but does not require stimulated SNARE binding. |