MULTIPLE SECONDARY PLANT PRODUCT UDP-GLUCOSE GLUCOSYLTRANSFERASE GENES EXPRESSED IN CASSAVA (MANIHOT-ESCULENTA CRANTZ) COTYLEDONS

Six different putative UDP-glucose glucosyltransferase clones were iso lated from a cassava cotyledon cDNA library probed with an Ace I-Bgl I I restriction fragment from a UDP-glucose flavonoid 3-O-glucosyltransf erase from Antirrhinum majus. The heterologous probe contained a gluco syltransferase consensus signature amino acid sequence which was also present in the cassava cDNA clones. Nucleotide and derived amino acid sequences are presented for two of the crones. Northern analysis showe d different patterns of expression for the six genes in developing see dling tissues, indicating temporal and tissue-specific regulation. A c omparative analysis was made of the six cassava clone derived amino ac id sequences and other reported UDP-glucosyltransferase genes. Highly conserved residues in plant genes from three species allow redefinitio n of essential residues within the signature sequence for secondary pl ant product metabolism glucosyltransferase genes.