4.8 Article

Unexpected Ca2+-binding properties of synaptotagmin 9

Publisher

NATL ACAD SCIENCES
DOI: 10.1073/pnas.0308477100

Keywords

C-2 domain; exocytosis; neurotransmitter release; synaptic plasticity; membrane fusion

Funding

  1. NINDS NIH HHS [R01 NS040944, NS40944] Funding Source: Medline

Ask authors/readers for more resources

Synaptotagmin 1 (Syt 1) functions as an essential Ca2+ sensor for the fast but not slow component of Ca2+-triggered exocytosis. One hypothesis to account for this selective function, based on the close homology of Syt 1 with synaptotagmin 9 (Syt 9), is that these Syts are redundant for the slow but not the fast component of release. We now show, however, that Syt 9 has unique properties that set it apart from Syt 1. Different from Syt 1, endogenous Syt 9 does not associate Ca2+ dependently or independently with soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNARE) protein complexes, and the Syt 9 C2B domain does not form Ca2+/phospholipid complexes, whereas such complexes are essential for Syt I function. Nevertheless, the C(2)A domain of Syt 9 functions as a Ca2+-binding module, suggesting that Syts 1 and 9 are Ca2+ sensors with similar Ca2+-binding sequences but distinct properties that indicate nonoverlapping functions.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.8
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available