FAR UPSTREAM ACTIVATING PROMOTER REGIONS ARE RESPONSIBLE FOR EXPRESSION OF THE BNC1 CRUCIFERIN GENE FROM BRASSICA-NAPUS

Cruciferin is the major seed storage protein in Brassica napus. As muc h as 1.9 kbp of the BnC1 cruciferin gene promoter have been sequenced and analyzed. Promoter fragments with 5' deletions from -2500 to -202 were fused with the beta-glucuronidase reporter gene and used for Nico tiana tabacum transformation. beta-glucuronidase could be specifically expressed in transgenic tobacco seeds under the control of the BnC1 p romoter and regulatory elements were found to be dispersed over 1903 b p. An almost 5-fold increase in beta-glucuronidase expression was obta ined when the promoter length was increased from -379 to -498, and ano ther 10-fold increase was observed when sequences between -1266 and -1 903 were added. Histochemical analysis shows that the region between - 844 and -1266 directs the expression of the chimeric gene specifically to the root apical meristem.