Figure 2. Proposed plant biosynthetic pathway and genes involved in the biosynthesis of BIAs from L-tyrosine to (S)-reticuline.

CYP80B, N-methylcoclaurine 3′-hydroxylase; NCS, norcoclaurine synthase; TH, tyrosine hydroxylase; TYDC, tyrosine/dopa decarboxylase; 4-HPAA, 4-hydroxyphenylacetaldehyde; 6OMT, norcoclaurine 6-O-methyltransferase; 4′OMT, 3′-hydroxy-N-methylcoclaurine 4′-O-methyltransferase.