- The multidomain protein Trio binds the LAR transmembrane tyrosine phosphatase, contains a protein kinase domain, and has separate rac-specific and rho-specific guanine nucleotide exchange factor domains. Debant, A., Serra-Pagès, C., Seipel, K., O'Brien, S., Tang, M., Park, S.H., Streuli, M. Proc. Natl. Acad. Sci. U.S.A. (1996)