Functional analysis of a Douglas-fir metallothionein-like gene promoter: transient assays in zygotic and somatic embryos and stable transformation in transgenic tobacco.

Douglas-fir (Pseudotsuga menziesii [Mirb] Franco) metallothionein (PmMT) cDNA encodes a novel cysteine- and serine-rich MT, indicating a new subtype or prototype MT from which other plant MTs may have evolved. A genomic library of Douglas-fir was screened using MT cDNA probes, and genomic sequences that mediate tissue-specific, temporal as well as inducible expression of the embryo-specific MT-gene were analyzed. The promoter region of the PmMT genomic clone (gPmMT) contained a hexameric G-box, two putative ethylene-responsive elements and an inverted repeat of a motif similar to the core metal regulatory element.

2S storage protein gene of Douglas-fir: characterization and activity of promoter in transgenic tobacco seeds.

To date a few sequences regulating expression of conifer seed-specific genes have been reported. To characterize Douglas-fir (Pseudotsuga menziesii [Mirb] Franco) 2S albumin storage protein genes, a genomic DNA sequence containing upstream promoter sequences was isolated by screening a Douglas-fir genomic library. Sequence analysis of the Douglas-fir gPm2S1 promoter revealed the presence of RY-repeated elements (GCATGC), and multiple E-box motifs (CANNTG) and ACGT-core elements, features characteristic of 2S storage protein genes in angiosperms.