The Ras superfamily, derived from "Rat sarcoma virus", is a

protein superfamily A protein superfamily is the largest grouping (clade) of proteins for which common ancestry can be inferred (see homology (biology), homology). Usually this common ancestry is inferred from structural alignment and mechanistic similarity, even if n ...

small GTPase Small GTPases (), also known as small G-proteins, are a family of hydrolase enzymes that can bind and hydrolyze guanosine triphosphate (GTP). They are a type of G-protein found in the cytosol that are homologous to the alpha subunit of heterotrim ...

s. Members of the superfamily are divided into

families Family (from ) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictability, structure, and safety as ...

and subfamilies based on their structure, sequence and function. The five main families are Ras,

Rho Rho (; uppercase Ρ, lowercase ρ or ; or ) is the seventeenth letter of the Greek alphabet. In the system of Greek numerals it has a value of 100. It is derived from Phoenician alphabet, Phoenician letter resh . Its uppercase form uses the same ...

Ran RAN may refer to: * Radio access network, a part of a mobile telecommunication system * Rainforest Action Network * Ran (gene) (RAs-related Nuclear protein), also known as GTP-binding nuclear protein Ran, a protein that in humans is encoded by t ...

Rab Rab may refer to: Places * Rab (island), an island in Croatia * Rab (town), on the island of Rab * Ráb, the Slovak name of Győr, a city in Hungary * Rąb, a village in Poland People * Rab (surname), includes a list of people with the n ...

and Arf GTPases. The Ras family itself is further divided into 6 subfamilies: Ras, Ral,

Rap Rapping (also rhyming, flowing, spitting, emceeing, or MCing) is an artistic form of vocal delivery and emotive expression that incorporates " rhyme, rhythmic speech, and ommonlystreet vernacular". It is usually performed over a backin ...

, Rheb, Rad and Rit. ''Miro'' is a recent contributor to the superfamily. Each subfamily shares the common core G domain, which provides essential GTPase and nucleotide exchange activity. The surrounding sequence helps determine the functional specificity of the small GTPase, for example the 'Insert Loop', common to the Rho subfamily, specifically contributes to binding to effector proteins such as

WASP A wasp is any insect of the narrow-waisted suborder Apocrita of the order Hymenoptera which is neither a bee nor an ant; this excludes the broad-waisted sawflies (Symphyta), which look somewhat like wasps, but are in a separate suborder ...

. In general, the Ras family is responsible for cell proliferation: Rho for cell

morphology Morphology, from the Greek and meaning "study of shape", may refer to: Disciplines *Morphology (archaeology), study of the shapes or forms of artifacts *Morphology (astronomy), study of the shape of astronomical objects such as nebulae, galaxies, ...

, Ran for nuclear transport, and Rab and Arf for

vesicle Vesicle may refer to: ; In cellular biology or chemistry * Vesicle (biology and chemistry), a supramolecular assembly of lipid molecules, like a cell membrane * Synaptic vesicle ; In human embryology * Vesicle (embryology), bulge-like features ...

transport.

Subfamilies and members

The following is a list of human proteins belonging to the Ras superfamily: Unclassified: *

ARHGAP5 Rho GTPase-activating protein 5 is an enzyme that in humans is encoded by the ''ARHGAP5'' gene. Function Rho GTPase activating protein 5 negatively regulates RHO GTPases, a family that may mediate cytoskeleton changes by stimulating the hydrol ...

* DNAJC27 * GRLF1 * RASEF

References

{{Portal bar, Biology, border=no G proteins Protein superfamilies

Subfamilies and members

See also

References