TRIO and F-actin-binding protein is a protein that in humans is encoded by the TRIOBP gene.

This gene encodes a protein with an N-terminal pleckstrin homology domain and a C-terminal coiled-coil region. The protein interacts with trio, which is involved with neural tissue development and controlling actin cytoskeleton organization, cell motility and cell growth. The protein also associates with F-actin and stabilizes F-actin structures. Mutations in this gene have been associated with a form of autosomal recessive nonsyndromic deafness. Multiple alternatively spliced transcript variants that would encode different isoforms have been found for this gene, however some transcripts may be subject to nonsense-mediated decay (NMD). [provided by RefSeq, Nov 2008].
Function: May regulate actin cytoskeletal organization, cell spreading and cell contraction by directly binding and stabilizing filamentous F-actin. The localized formation of TARA and TRIO complexes coordinates the amount of F-actin present in stress fibers. May also serve as a linker protein to recruit proteins required for F-actin formation and turnover.