Mutually exclusive binding of domain pairs to the same protein segment.

Summary of literature-documented double switches. The second column includes protein sequences, where residues vital for SH2 binding and residues vital for SH3/class I WW binding are in bold and underlined, respectively. Rows (1–3) describe experimentally-verified double switches. Rows (4–5) include examples for which there is evidence for the motif binding to each domain, but not for a direct switch. Note that Y534 in growth hormone receptor is phosphorylated according to a high-throughput experiment. Also note that evidence for Fyn-Cbl interaction exists for the Cbl (552–614) fragment (spanning 62 residues), where Y552 is the only tyrosine, suggesting that this tyrosine is bound by the SH2 domain in Fyn.