[8] The N-terminal region of paxillin has five highly conserved leucine-rich sequences termed LD motifs, which mediate several interactions, including that with pp125FAK and vinculin.

Paxillin is tyrosine-phosphorylated by FAK and Src upon integrin engagement or growth factor stimulation,[14] creating binding sites for the adapter protein Crk.

The current working model of costamerogenesis is that in cultured, undifferentiated myoblasts, alpha-5 integrin, vinculin and paxillin are in complex and located primarily at focal adhesions.

The proline-rich region of paxillin specifically binds to the second SH3 domain of ponsin, which occurs after the onset of the myogenic differentiation and with expression restricted to costameres.

[22] These data show that alterations in costameric organization, in part via paxillin redistribution, may be a pathogenic mechanism in dilated cardiomyopathy.

[24] Mutations in PXN have been associated with enhanced tumor growth, cell proliferation, and invasion in lung cancer tissues.

[26] Paxillin plays a role in the MET tyrosine kinase signaling pathway, which is upregulated in many cancers.