Paxillin is an approximately 68-kDa multi-domain adapter protein featuring 5 LD motifs and 4 LIM domains. It is mainly a cytoplasmic protein enriched at focal adhesions in adherent cells but it can also translocate to the nucleus. Paxillin located at focal adhesions is one of linkers connecting extracellular matrix to the actin cytoskeleton. Paxillin is subject to tyrosine and serine/threonine phosphorylation. It is involved in cell signaling by integrins and growth factor receptors, cell adhesion and motility, and tumor growth and metastasis.
Structure and Binding Partners
The human paxillin gene (gene symbol: PXN) is located on chromosome 12q24.31. There are four transcript variants. Paxillin α (commonly referred to as paxillin) is encoded by the predominant transcript isoform 1 and has 557 amino acid residues (NCBI reference sequence: NP_002850.2). Paxillin is expressed ubiquitously except in platelets.