Domain

Synaptotagmin-like protein 4/5, C2A domain (IPR037303)

Short name: SLP-4/5_C2A

Overlapping homologous superfamilies

Domain relationships

  • C2 domain (IPR000008)
    • Synaptotagmin-like protein 4/5, C2A domain (IPR037303)

Description

Synaptotagmin-like proteins (Slps) contain a N-terminal RabBD (Rab-binding) domain and two C-terminal C2 domains, C2A and C2B [PMID: 14745138]. The characteristic feature of the Slp family is the N-terminal domain (referred to as SHD for Slp Homology Domain), which is not found in other C-type tandem C2 proteins [PMID: 12051743]. SHD functions as a specific Rab27A/B-binding domain [PMID: 11773082]. The C2B domain of Slp4 (also known as Granuphilin) interact with the plasma membrane lipid phosphatidylinositol-(4,5)-bisphosphate [PI(4,5)P2] [PMID: 24184645].

C2 domains fold into an 8-standed beta-sandwich that can adopt 2 structural arrangements, type I and type II, distinguished by a circular permutation involving their N- and C-terminal beta strands. Many C2 domains are Ca2+-dependent membrane-targeting modules that bind a wide variety of substances including phospholipids, inositol polyphosphates, and intracellular proteins. Most C2 domain proteins are either signal transduction enzymes that contain a single C2 domain, such as protein kinase C, or membrane trafficking proteins which contain at least two C2 domains, such as synaptotagmin 1. However, there are a few exceptions to this including RIM isoforms and some splice variants of piccolo/aczonin and intersectin which only have a single C2 domain. C2 domains with a calcium binding region have negatively charged residues, primarily aspartates, that serve as ligands for calcium ions [PMID: 9632630, PMID: 8976547, PMID: 8771209, PMID: 8662510, PMID: 7791877, PMID: 7697723, PMID: 1589771, PMID: 2333096].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005543 phospholipid binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
CDD