Cloning and genomic characterization of tomato sterol methyl transferase 1 involved in sterol pathway

Introduction of tomato sterol methyl transferase terols from higher plants and fungi present an S group at C24 that is absent in vertebrate sterols!. In vascular plants, at least three SMT iso-forms are present to control the pattern of phyto-sterols². Cycloartenol is the substrate of the first methylation reaction catalyzed by SMTI resulting B in 24-methylene cycloartenol synthesis, whereas 24-methylene lophenol is the preferred substrate for the second methylation step catalyzed by SMT2 or SMT3 yielding to 24-ethylidene lophenob. In Arabi dopsis, SMT2 and SMT3, which also encode a C-24 sterol methyltransferase, catalyze the reaction distinguishes the synthesis of structural sterols fo signaling brassinosteroid derivatives. In the present work, we cloned and characterized a tomato SM77 gene involved in the first steps of sterol biosynthesis.