Function

The WH2 motif or WH2 domain is an evolutionarily conserved

sequence motif In biology, a sequence motif is a nucleotide or amino-acid sequence pattern that is widespread and usually assumed to be related to biological function of the macromolecule. For example, an ''N''-glycosylation site motif can be defined as ''As ...

contained in

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

s. It is found in

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. Th ...

proteins which control actin polymerisation, therefore, WH2 is important in cellular processes such as cell contractility, cell motility, cell trafficking and cell signalling.

Motif

The WH2 motif (for

Wiskott–Aldrich syndrome Wiskott–Aldrich syndrome (WAS) is a rare X-linked recessive disease characterized by eczema, thrombocytopenia (low platelet count), immune deficiency, and bloody diarrhea (secondary to the thrombocytopenia). It is also sometimes called the eczem ...

homology region 2) has been shown in

WAS Was or WAS may refer to: * ''Was'', a past-tense form of the English copular verb ''to be'' People * David Was (born c. 1952), the stage name of multi-instrumentalist and songwriter David Weiss * Don Was (born 1952), the stage name of bass guita ...

and Scar1/WASF1 (mammalian homologue) to interact via their WH2 motifs with

actin Actin is a family of globular multi-functional proteins that form microfilaments in the cytoskeleton, and the thin filaments in muscle fibrils. It is found in essentially all eukaryotic cells, where it may be present at a concentration of over ...

. The WH2 (WASP-Homology 2, or Wiskott–Aldrich homology 2) domain is an ~18 amino acids actin-binding motif. This domain was first recognized as an essential element for the regulation of the

cytoskeleton The cytoskeleton is a complex, dynamic network of interlinking protein filaments present in the cytoplasm of all cells, including those of bacteria and archaea. In eukaryotes, it extends from the cell nucleus to the cell membrane and is compos ...

by the mammalian Wiskott–Aldrich syndrome protein (WASP) family. WH2 proteins occur in eukaryotes from yeast to mammals, in insect viruses, and in some bacteria. The WH2 domain is found as a modular part of larger proteins; it can be associated with the WH1 or

EVH1 domain WH1 domain is an evolutionary conserved protein domain. Therefore, it has an important function. Function WH1 domains are found on WASP proteins, which are often involved in actin polymerization. Hence, WH1 is important for all cellular process ...

and with the CRIB domain, and the WH2 domain can occur as a tandem repeat. The WH2 domain binds to actin monomers and can facilitate the assembly of actin monomers into actin filaments.

Examples

Human genes encoding proteins containing the WH2 motif include: * COBL,

COBLL1 Cordon-bleu protein-like 1 is a protein that in humans is encoded by the ''COBLL1'' gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation' ...

ESPN ESPN (originally an initialism for Entertainment and Sports Programming Network) is an American international basic cable sports channel owned by ESPN Inc., owned jointly by The Walt Disney Company (80%) and Hearst Communications (20%). The ...

INF2 Inverted formin-2 is a protein that in humans is encoded by the ''INF2'' gene. It belongs to the protein family called the formins. It has two splice isoforms, CAAX which localizes to the endoplasmic reticulum and non-CAAX which localizes to foca ...

, JMY * LMOD1, LMOD2,

LMOD3 Leiomodin-3 is a protein that in humans is encoded by the ''LMOD3'' gene. Leiomodin-3 is especially present at the pointed end of muscle thin filaments. Clinical significance Dysfunction is associated with thin filament disorganisation and nemali ...

MTSS1 Metastasis suppressor protein 1 is a protein that in humans is encoded by the ''MTSS1'' gene. True to its name, it codes for a metastasis suppressor A metastasis suppressor is a protein that acts to slow or prevent metastases (secondary tumors) f ...

PXK PX domain containing serine/threonine kinase also known as PXK is a protein which in humans is encoded by the ''PXK'' gene. Function PXK binds to the Na⁺/K⁺-ATPase beta-1 ( ATP1B1) and beta-3 ( ATP1B3) subunits and modulates both Na⁺/K� ...

WASF1 Wiskott–Aldrich syndrome protein family member 1, also known as WASP-family verprolin homologous protein 1 (WAVE1), is a protein that in humans is encoded by the ''WASF1'' gene. Function The protein encoded by this gene, a member of the Wisko ...

WASF2 Wiskott-Aldrich syndrome protein family member 2 is a protein that in humans is encoded by the ''WASF2'' gene. This gene encodes a member of the Wiskott-Aldrich syndrome protein family. The gene product is a protein that forms a multiprotein comp ...

WASF3 Wiskott-Aldrich syndrome protein family member 3 is a protein that in humans is encoded by the ''WASF3'' gene. This gene encodes a member of the Wiskott-Aldrich syndrome protein family. The gene product is a protein that forms a multiprotein comp ...

, WASF4, WASL, WASPIP, WHDC1,

WIPF1 WAS/WASL-interacting protein (WIP) is a protein that in humans is encoded by the ''WIPF1'' gene. Function This gene encodes a protein that plays an important role in the organization of the actin cytoskeleton. Overexpression of WIP in mammalia ...

WIPF2 WAS/WASL-interacting protein family member 2 is a protein that in humans is encoded by the ''WIPF2'' gene. This gene encodes a WASP interacting protein (WIP)-related protein. It has been shown that this protein has a role in the WASP-mediated org ...

References

Protein domains Protein families Membrane proteins {{membrane-protein-stub