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Synapsin I is structurally similar to ATP-utilizing enzymes.

ABSTRACT: Synapsins are abundant synaptic vesicle proteins with an essential regulatory function in the nerve terminal. We determined the crystal structure of a fragment (synC) consisting of residues 110-420 of bovine synapsin I; synC coincides with the large middle domain (C-domain), the most conserved domain of synapsins. SynC molecules are folded into compact domains and form closely associated dimers. SynC monomers are strikingly similar in structure to a family of ATP-utilizing enzymes, which includes glutathione synthetase and D-alanine:D-alanine ligase. SynC binds ATP in a Ca2+-dependent manner. The crystal structure of synC in complex with ATPgammaS and Ca2+ explains the preference of synC for Ca2+ over Mg2+. Our results suggest that synapsins may also be ATP-utilizing enzymes.

SUBMITTER: Esser L

PROVIDER: S-EPMC1170447 | biostudies-other | 1998 Feb

REPOSITORIES: biostudies-other

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Synapsin I is structurally similar to ATP-utilizing enzymes.

Esser L L Wang C R CR Hosaka M M Smagula C S CS Südhof T C TC Deisenhofer J J

The EMBO journal 19980201 4

Synapsins are abundant synaptic vesicle proteins with an essential regulatory function in the nerve terminal. We determined the crystal structure of a fragment (synC) consisting of residues 110-420 of bovine synapsin I; synC coincides with the large middle domain (C-domain), the most conserved domain of synapsins. SynC molecules are folded into compact domains and form closely associated dimers. SynC monomers are strikingly similar in structure to a family of ATP-utilizing enzymes, which include ...[more]

PMID: 9463376

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