5H4Z

Crystal structure of S202G mutant of human SYT-5 C2A domain

Summary for 5H4Z

• Entry DOI: 10.2210/pdb5h4z/pdb
• Related: 5H4Y
• Descriptor: Synaptotagmin-5, CALCIUM ION, CHLORIDE ION, ... (4 entities in total)
• Functional Keywords: metal binding protein, mutant
• Biological source: Homo sapiens (Human)
• Cellular location: Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane ; Single-pass membrane protein : O00445
• Total number of polymer chains: 2
• Total formula weight: 34578.76

Authors

Qiu, X.,Ge, J.,Yan, X.,Gao, Y.,Teng, M.,Niu, L. (deposition date: 2016-11-02, release date: 2016-11-30, Last modification date: 2023-11-08)

Primary citation

Qiu, X.,Ge, J.,Gao, Y.,Teng, M.,Niu, L.
Structural analysis of Ca(2+)-binding pocket of synaptotagmin 5 C2A domain
Int. J. Biol. Macromol., 95:946-953, 2017

PubMed Abstract: Synaptotagmins constitute a family of multifunctional integral membrane proteins found predominantly on vesicles in neural and endocrine tissues. 17 isoforms of synaptotagmin family in mammals have been identified, 7 isoforms among them are known to be able to bind Ca via their C2 domains. This study presents the crystal structure of the first C2 domain (C2A domain) of synaptotagmin 5 complexed with Ca at 1.90Å resolution. Comparison of the Ca-binding pocket of synaptotagmin 5 C2A domain with other synaptotagmin C2 domains demonstrated that a serine residue locating at Ca-binding loop probably responsible to the conformational variation of Ca-binding pocket, and thus impacts the Ca-binding mechanism of C2 domain, which is verified by structural analysis of the serine mutant and Ca-binding assays via isothermal titration calorimetry. Alteration of Ca-binding mechanism might be correlated with different Ca response rates of synaptotagmins, which is the basis of the functions of synaptotagmins in regulating various types of Ca-triggered vesicle-membrane fusion processes.

PubMed: 27793683
DOI: 10.1016/j.ijbiomac.2016.10.083

Experimental method

X-RAY DIFFRACTION (3.01 Å)