Domain

Dynamin-type guanine nucleotide-binding (G) domain (IPR030381)

Short name: G_DYNAMIN_dom

Domain relationships

Description

This entry represents the dynamin-type guanine nucleotide-binding (G) domain.

Members of the dynamin GTPase family appear to be ubiquitous. They catalyze diverse membrane remodelling events in endocytosis, cell division, and plastid maintenance. Their functional versatility also extends to other core cellular processes, such as maintenance of cell shape or centrosome cohesion. Members of the dynamin family are characterised by their common structure and by conserved sequences in the GTP-binding domain. The minimal distinguishing architectural features that are common to all dynamins and are distinct from other GTPases are the structure of the large GTPase domain (~280 amino acids) and the presence of two additional domains: the middle domain and the GTPase effector domain (GED), which are involved in oligomerization and regulation of the GTPase activity. In many dynamin family members, the basic set of domains is supplemented by targeting domains, such as: pleckstrin-homology (PH) domain, proline-rich domains (PRDs), or by sequences that target dynamins to specific organelles, such as mitochondria and chloroplasts [PMID: 11916378, PMID: 10201074, PMID: 15040446].

The dynamin-type G domain consists of a central eight-stranded beta-sheet surrounded by seven alpha helices and two one-turn helices. It contains the five canonical guanine nucleotide binding motifs (G1-5). The P-loop (G1) motif (GxxxxGKS/T) is also present in ATPases (Walker A motif) and functions as a coordinator of the phosphate groups of the bound nucleotide. A conserved threonine in switch-I (G2) and the conserved residues DxxG of switch-II (G3) are involved in Mg(2+) binding and GTP hydrolysis. The nucleotide binding affinity of dynamins is typically low, with specificity for GTP provided by the mostly conserved N/TKxD motif (G4). The G5 or G-cap motif is involved in binding the ribose moiety [PMID: 21927001, PMID: 23977156, PMID: 21962493].

Some proteins containing a dynamin-type G domain are listed below [PMID: 10201074, PMID: 15040446]:

  • Animal dynamin, the prototype for this family. The role of dynamin in endocytosis is well established. Additional roles were proposed in vesicle budding from the trans-Golgi network (TGN) and the budding of caveolae from the plasma membrane [PMID: 21927001].
  • Vetebrate Mx proteins, a group of interferon (IFN)-induced GTPases involved in the control of intracellular pathogens [PMID: 21962493, PMID: 24296571].
  • Eukaryotic Drp1 (Dnm1 in yeast) mediates mitochondrial and peroxisomal fission.
  • Eukaryotic Eps15 homology (EH)-domain-containing proteins (EHDs), ATPases implicated in clathrin-independent endocytosis and recycling from endosomes. The dynamin-type G domains of EHDs bind to adenine rather than to guanine nucleotide [PMID: 17914359, PMID: 24508342].
  • Yeast to human OPA1/Mgm1 proteins. They are found between the inner and outer mitochondrial membranes and are involved in mitochondrial fusion.
  • Yeast to human mitofusin/fuzzy onions 1 (Fzo1) proteins, involved in mitochondrial dynamics [PMID: 23223037, PMID: 21502136].
  • Yeast vacuolar protein sorting-associated protein 1 (Vps1), involved in vesicle trafficking from the Golgi.
  • Escherichia coli clamp-binding protein CrfC (or Yjda), important for the colocalization of sister nascent DNA strands after replication fork passage during DNA replication, and for positioning and subsequent partitioning of sister chromosomes [PMID: 23994470].
  • Nostoc punctiforme bacterial dynamin-like protein (BDLP) [PMID: 20970992, PMID: 20064379].

GO terms

Biological Process

No terms assigned in this category.

Molecular Function

GO:0005525 GTP binding

Cellular Component

No terms assigned in this category.

Contributing signatures

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