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 ''A ...

contained in

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

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 ...

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 e ...

homology region 2) has been shown in WAS 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 ...

. 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 domains, also known as EVH1 domains, are evolutionary conserved protein domain, protein domains found on WASP (VASP) proteins, which are often involved in actin polymerization. Function WH1 domains are important for all cellular processes i ...

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,

ESPN ESPN (an initialism of their original name, which was the Entertainment and Sports Programming Network) is an American international basic cable sports channel owned by the Walt Disney Company (80% and operational control) and Hearst Commu ...

, INF2, 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 In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA ...

, PXK * WAS, WASF1, WASF2, WASF3, WASF4, WASL, WASPIP, WHDC1, WIPF1, WIPF2

References

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