CHARACTERIZATION OF A GENOMIC CLONE FOR A MAIZE DNAJ-RELATED GENE, ZMDJ1, AND EXPRESSION ANALYSIS OF ITS PROMOTER IN TRANSGENIC PLANTS

A novel promoter from maize is described which confers a 'tissue-gener al' pattern of expression. During a search for novel tissue-specific o r constitutively expressed promoters, a clone was recovered which by n orthern analysis exhibited expression in a variety of maize tissues. S equence evaluation revealed that this gene has substantial sequence si milarity to genes from the DnaJ class of molecular chaperone proteins. A genomic clone for this gene, ZmdJ1, was recovered and the 5' upstre am regulatory regions isolated and used to evaluate expression of a re porter gene in transgenic maize. Relative to the strong 'constitutive' CaMV 35S promoter, the ZmdJ1 promoter drives GUS expression at modera te levels in a variety of seedling and mature plant tissues, and provi des an alternative promoter for use in driving gene expression in tran sgenic plant tissues. Our studies are the first to describe and charac terize a promoter from a member of the DnaJ or DnaJ-related classes of genes in a higher eukaryote.