M. Mazarei et al., FUNCTIONAL-ANALYSIS OF THE RUBISCO LARGE SUBUNIT N-EPSILON-METHYLTRANSFERASE PROMOTER FROM TOBACCO AND ITS REGULATION BY LIGHT IN SOYBEAN HAIRY ROOTS, Plant cell reports, 17(12), 1998, pp. 907-912
The ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) large su
bunit (LS) N-epsilon-methyltransferase (Rubisco LSMT) catalyzes post-t
ranslational methylation of the epsilon-amino group of lysine-14 in th
e LS of Rubisco. The entire nucleotide sequence for the tobacco (Nicot
iana tabacum) Rubisco LSMT (rbcMT-T) gene including the putative promo
ter region was recently reported, and sequence analysis of the promote
r region revealed seven GT-1 motifs. The ability of several truncated
rbcMT-T promoter fragments to confer light responsiveness to reporter
gene expression in transgenic soybean (Glycine max:) hairy roots was e
xamined. Chimeric constructs consisting of the rbcMT-T promoter fused
to a bacterial beta-glucuronidase (GUS) reporter gene and transferred
to soybean via Agrobacterium rhizogenes were evaluated. The rbcMT-T pr
o meter fragments conferred expression of the reporter gene in transge
nic hairy roots, callus, and cell suspension cultures based on histoch
emical and fluorometric GUS analyses. The results suggest a quantitati
ve role for the number of GT-1 motifs in determining differential expr
ession between light and dark conditions.