PROMOTER ACTIVITY OF THE 5'-FLANKING REGION OF A TOBACCO GLYCOLATE OXIDASE GENE IN TRANSGENIC TOBACCO PLANTS

A clone harboring the 5' flanking region of a tobacco glycolate oxidas e (GLO) gene was isolated from a lambda EMBL3-tobacco genomic DNA liba rary. Primer extension analysis indicated two major transcripts with 7 6 and 81 bp 5' UTRs. An RT-PCR assay mapped the major mRNA transcripti on initiation site to thymine at position 81 upstream of the translati on initiation codon. A putative TATA box spanning positions -56 to -50 upstream of the transcription initiation site was found. Promoter act ivity of the 5' flanking region (-3.0 kb to +82 bp) was demonstrated i n tobacco plants transformed with a GLO-beta-glucuronidase (GUS) chime ric gene. Furthermore, in these transgenic plants, GUS expression patt erns mimicked the expression patterns of the endogenous GLO. (C) 1998 Elsevier Science B.V. All rights reserved.