Transcription factor involved in jasmonic acid (JA) gene regulation. With MYC2 and MYC3, controls additively subsets of JA-dependent responses. Can form complexes with all known glucosinolate-related MYBs to regulate glucosinolate biosynthesis. Binds to the G-box (5'-CACGTG-3') of promoters. Activates multiple TIFY/JAZ promoters. Homo- and heterodimer. Interacts with MYB28, MYB29, MYB34, MYB51, MYB76, MYB122, MYC3, AFPH2/NINJA and the JAZ repressors TIFY10A/JAZ1, TIFY10B/JAZ2, TIFY6B/JAZ3, TIFY6A/JAZ4, TIFY11A/JAZ5, TIFY11B/JAZ6, TIFY5B/JAZ7, TIFY5A/JAZ8, TIFY7/JAZ9, TIFY9/JAZ10, TIFY3A/JAZ11 and TIFY3B/JAZ12. Expressed constitutively at low levels. Preferentially expressed in vascular tissues. By UV treatment. Not induced by jasmonic acid. The JAZ-interaction domain (JID) (99-150) is sufficient for interaction with MYB proteins and most of the TIFY/JAZ proteins. Minor effect on jasmonic acid response and no effect on glucosinolate biosynthesis. Myc2 and myc4 double mutant has an increased insensitivity to jasmonic acid. Myc2, myc3 and myc4 triple mutant has no jasmonate-related defense response, is devoid of glucosinolates and is extremely susceptible to generalist herbivores.