WAS/WASL-interacting protein (WIP) is a protein that in humans is encoded by the WIPF1 gene. [5] [6]
WAS/WASL-interacting protein (WIP) is a protein that in humans is encoded by the WIPF1 gene. [5] [6]
This gene encodes a protein that plays an important role in the organization of the actin cytoskeleton. Overexpression of WIP in mammalian cells has been shown to increase actin polymerization. [5] The encoded protein binds to a region of Wiskott–Aldrich syndrome protein that is frequently mutated in Wiskott–Aldrich syndrome, an X-linked recessive disorder. Impairment of the interaction between these two proteins may contribute to the disease. Two transcript variants encoding the same protein have been identified for this gene. [6] In patients lacking the WIPF1 gene WASp protein levels are depleted and WAS symptoms present. [7]
WIP has been shown to interact with Wiskott–Aldrich syndrome protein, [5] [8] N-WASp, Cortactin, [9] NCK1, [8] MYO1e [10] and ITSN1. [11] While Wiskott–Aldrich syndrome protein (WASp)is expressed only in haematopoetic cells, WIPF1 is expressed ubiquitously. [5] The majority of the mutations causing Wiskott Aldrich Syndrome are located in the WH1 domain of WASp. [12] These mutations affect WASp-WIPF1 binding. [13] WIPF1 has an N-terminal profilin binding domain, two actin binding WH2 domains, a central polyproline stretch, and a C-terminal WASp Binding Domain. WASp protein is degraded in the absence of WIP; but the ubiquitously expressed WASp ortholog N-WASp remains stable in the absence of WIP.
WIPF1 functions and interactions have been studied in multiple fungal systems including Saccharomyces cerevisiae , Schizosaccharomyces pombe , Candida albicans , [14] and Magnaporthe grisea . [15]
Yeast Vrp1 is recruited to sites of endocytosis by WASp homologs. Here it interacts with myosin-1 and enhances myosin-1 mediated activation of the Arp2/3 complex. [16] In addition to a role in endocytosis, Saccharomyces cerevisiae Vrp1 functions in cytokinesis and cell polarization. [17]
In Schizosaccharomyces pombe , Vrp1 interaction with myosin-1 is believed to help position new actin branches near the membrane, enhancing the amount of force against the membrane. This interaction is disrupted by the yeast specific protein Bbc1/Mti1/SPAC23A1.17, which competes with Vrp1 for binding the Myo1e homolog. [18]
The Wiskott–Aldrich syndrome protein (WASp) is a 502-amino acid protein expressed in cells of the hematopoietic system that in humans is encoded by the WAS gene. In the inactive state, WASp exists in an autoinhibited conformation with sequences near its C-terminus binding to a region near its N-terminus. Its activation is dependent upon CDC42 and PIP2 acting to disrupt this interaction, causing the WASp protein to 'open'. This exposes a domain near the WASp C-terminus that binds to and activates the Arp2/3 complex. Activated Arp2/3 nucleates new F-actin.
Cortactin is a monomeric protein located in the cytoplasm of cells that can be activated by external stimuli to promote polymerization and rearrangement of the actin cytoskeleton, especially the actin cortex around the cellular periphery. It is present in all cell types. When activated, it will recruit Arp2/3 complex proteins to existing actin microfilaments, facilitating and stabilizing nucleation sites for actin branching. Cortactin is important in promoting lamellipodia formation, invadopodia formation, cell migration, and endocytosis.
Cell division control protein 42 homolog is a protein that in humans is encoded by the CDC42 gene. Cdc42 is involved in regulation of the cell cycle. It was originally identified in S. cerevisiae (yeast) as a mediator of cell division, and is now known to influence a variety of signaling events and cellular processes in a variety of organisms from yeast to mammals.
Actin-related protein 3 is a protein that in humans is encoded by the ACTR3 gene.
Actin-related protein 2 is a protein that in humans is encoded by the ACTR2 gene.
Dynamin-2 is a protein that in humans is encoded by the DNM2 gene.
Wiskott–Aldrich syndrome protein family member 2 is a protein that in humans is encoded by the WASF2 gene.
Cytoplasmic protein NCK1 is a protein that in humans is encoded by the NCK1 gene.
Neural Wiskott–Aldrich syndrome protein is a protein that in humans is encoded by the WASL gene.
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.
CD2-associated protein is a protein that in humans is encoded by the CD2AP gene.
Engulfment and cell motility protein 1 is a protein that in humans is encoded by the ELMO1 gene. ELMO1 is located on chromosome number seven in humans and is located on chromosome number thirteen in mice.
Ena/VASP-like protein is a member of the Ena/VASP family of proteins that in humans is encoded by the EVL gene.
Wiskott–Aldrich syndrome protein family member 3 is a protein that in humans is encoded by the WASF3 gene.
NCK-interacting protein with SH3 domain is a protein that in humans is encoded by the NCKIPSD gene.
60S ribosomal protein L13 is a protein that in humans is encoded by the RPL13 gene.
Protein cordon-bleu is a protein that in humans is encoded by the COBL gene.
The Actin assembly-inducing protein (ActA) is a protein encoded and used by Listeria monocytogenes to propel itself through a mammalian host cell. ActA is a bacterial surface protein comprising a membrane-spanning region. In a mammalian cell the bacterial ActA interacts with the Arp2/3 complex and actin monomers to induce actin polymerization on the bacterial surface generating an actin comet tail. The gene encoding ActA is named actA or prtB.
WH1 domain is an evolutionary conserved protein domain found on WASP proteins, which are often involved in actin polymerization.
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