SH3 adapter protein SPIN90 (NCK-interacting protein with SH3 domain, SH3 protein interacting with Nck 90 kD, VacA-interacting protein 54 kD, VIP54, AF3p21, diaphanous protein-interacting protein, Dia-interacting protein 1, DIP-1, NCKIPSD, AF3P21, SPIN90)

Function

• role in stress fiber formation induced by active DRF1
• induces microspike formation, in vivo
• in vitro, stimulates N-WASP-induced ARP2/3 complex activation in the absence of CDC42
• role in maintenance of sarcomeres &/or in the assembly of myofibrils into sarcomeres
• implicated in regulation of actin polymerization & cell adhesion
• associates with intermediate filaments, vimentin & desmin
• binds 1st & 3rd SH3 domains of NCK
• binds proline-rich domains of N-WASP via its SH3 domain
• binds DRF1
• binds SH3 domains of GRB2 via its proline-rich domains

Structure

contains 1 SH3 domain

Compartment

• nucleus
• colocalizes with DRF1 at membrane ruffles, & with Nck at Z-disks in mature cardiac myocytes

Alternative splicing

named isoforms=2

Expression

• expressed in heart, brain, skeletal muscle, kidney, liver > placenta, lung, small intestine, leukocytes > colon, thymus, spleen.

Pathology

• chromosomal translocation t(3;11)(p21;q23) involving NCKIPSD with MLL is found in therapy-related leukemia

More general terms

• nuclear protein

Database

• OMIM: https://mirror.omim.org/entry/606671
• UniProt: http://www.uniprot.org/uniprot/Q9NZQ3.html