Domain

NT-type C2 domain (IPR019448)

Short name: NT-C2

Overlapping homologous superfamilies

None.

Domain relationships

None.

Description

The C2 domain is one of the most prevalent eukaryotic lipid-binding domains deployed in diverse functional contexts. Many C2 domains bind directly to membrane lipids and display a wide range of lipid selectivity, with preference for anionic phosphatidylserine (PS) and phosphatidylinositol-phosphates (PIPs).

Despite their limited sequence similarity, all C2 domains contain at their core a compact beta-sandwich composed of two four-stranded beta sheets with highly variable inter-strand regions that might contain one or more alpha- helices.

The NT-type C2 domain shows a diverse range of domain architectures but it is nearly always found at the N-termini of proteins that contain it. Hence, it has been named the N-terminal C2 (NT-C2) family. It is typically coupled with a coiled-coil domain, that could mediate di/oligo-merization and the DIL (Dilute) domain. It is also coupled with the Calponin homology (CH) domain in EHBP1 proteins, Filamin/ABP280 repeats and Mg2+ transporter MgtE N-terminal domain in proteins from chlorophyte algae such as Micromonas and Ostreococcus tauri. Thus, a common theme across the NT-type C2 domain proteins is the combination to several different domains with microfilament-binding or actin-related roles (i.e. such as CH, DIL, and Filamin). Other conserved groups of the NT-type C2 proteins prototyped by EEIG1, PMI1, and SYNC1 have their own distinct C- terminal conserved extensions that are restricted to these groups and might mediate specific interactions. The primary function of the NT-type C2 domain appears to be the linking of actin/microfilament-binding adaptors to the membrane and to act as a link that tethers endosomal vesicles to the cytoskeleton in course of their intracellular trafficking [PMID: 20713135, PMID: 27272733].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam
PROSITE profiles