tyrosine phosphorylation of STAT protein obsolete JAK-induced STAT protein dimerization true JAK-induced STAT protein dimerization GO:0007261 This term was made obsolete because it is ambiguous, and protein dimerization is represented by molecular function terms. biological_process OBSOLETE. The formation of a dimer of two STAT proteins (Signal Transducers and Activators of Transcription) following their activation by members of the janus activated kinase (JAK) family of tyrosine kinases. protein dimerization activity