Abstract
Talin2 is localized to large focal adhesions and is indispensable for traction force generation, invadopodium formation, cell invasion as well as metastasis. Talin2 has a higher affinity toward β-integrin tails than talin1. Moreover, disruption of the talin2-β-integrin interaction inhibits traction force generation, invadopodium formation and cell invasion, indicating that a strong talin2-β-integrin interaction is required for talin2 to fulfill these functions. Nevertheless, the role of talin2 in mediation of these processes remains unknown. Here we show that talin2 binds to the N-terminus of non-muscle myosin IIA (NMIIA) through its F3 subdomain. Moreover, talin2 co-localizes with NMIIA at cell edges as well as at some cytoplasmic spots. Talin2 also co-localizes with cortactin, an invadopodium marker. Furthermore, overexpression of NMIIA promoted the talin2 head binding to the β1-integrin tail, whereas knockdown of NMIIA reduced fibronectin and matrix metalloproteinase secretion as well as inhibited cell attachment on fibronectin-coated substrates. These results suggest that talin2 binds to NMIIA to control the secretion of extracellular matrix proteins and this interaction modulates cell adhesion.