The Ras superfamily, derived from "Rat sarcoma virus", is a
protein superfamily of
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 heterotr ...
s.
Members of the superfamily are divided into
families
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...
and subfamilies based on their structure, sequence and function. The five main families are Ras,
Rho,
Ran,
Rab and
Arf
ARF may refer to:
Organizations
* Advertising Research Foundation
* Animal Rescue Foundation
* Armenian Revolutionary Federation
* ASEAN Regional Forum
People
* Cahit Arf (1910–1997), Turkish mathematician
Science, medicine, and mathematics
* ...
GTPases.
The Ras family itself is further divided into 6 subfamilies:
Ras,
Ral,
Rap
Rapping (also rhyming, spitting, emceeing or MCing) is a musical form of vocal delivery that incorporates "rhyme, rhythmic speech, and street vernacular". It is performed or chanted, usually over a backing beat or musical accompaniment. The ...
,
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 transport.
[
]
Subfamilies and members
The following is a list of human proteins belonging to the Ras superfamily: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
See also
* Ras subfamily
References
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G proteins
Protein superfamilies