Photoregulation of a Phytochrome Gene Promoter from Oat Transferred into Rice by Particle Bombardment

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 86; no. 24; pp. 9692 - 9696
• Main Authors: Bruce, Wesley B., Christensen, Alan H., Klein, Theodore, Fromm, Michael, Quail, Peter H.
• Format: Journal Article
• Language: English
• Published: Washington, DC National Academy of Sciences of the United States of America 01.12.1989; National Acad Sciences
• Subjects: Barley; Biological and medical sciences; Chloramphenicol O-Acetyltransferase - genetics; Cucumbers; Edible Grain - genetics; Fundamental and applied biological sciences. Psychology; Gene Expression; Gene expression regulation; gene transfer; Genes; Genes, Plant - radiation effects; Genes, Regulator - radiation effects; Introns; Irradiation; Kinetics; Light; Messenger RNA; Molecular and cellular biology; Molecular genetics; Oats; Oryza - genetics; Oryza sativa; Phytochrome - genetics; Plant Proteins - genetics; Plants - genetics; Plasmids; Promoter Regions, Genetic - radiation effects; Rice; Seedlings; Transcription, Genetic - radiation effects; Avena sativa; Monocotyledones; Intergeneric hybridization; Arabidopsis thaliana; Promoter; Oryza sativa; Gene; Cruciferae; Gramineae; Dicotyledones; Angiospermae; Heterologous system; Hordeum vulgare; Radiolabelling; Nucleotide sequence; Homologous system; Flanking sequence; Gene expression; Genetic transfer; Enzymatic method; Phytochrome; Restriction map; Irradiation; Spermatophyta; Photoregulation
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.86.24.9692

The regulatory photoreceptor phytochrome controls the transcription of its own phy genes in a negative feedback fashion. We have exploited microprojectile-mediated gene transfer to develop a rapid transient expression assay system for the study of DNA sequences involved in the phytochrome-regulated expression of these genes. The 5′-flanking sequence and part of the structural region of an oat phy gene have been fused to a reporter coding sequence (chloramphenicol acetyltransferase, CAT) and introduced into intact darkgrown seedlings by using high-velocity microprojectiles. Expression is assayable in <24 hr from bombardment. The introduced oat phy-CAT fusion gene is expressed and down-regulated by white light in barley, rice, and oat, whereas no expression is detected in three dicots tested, tobacco, cucumber, and Arabidopsis thaliana. In bombarded rice shoots, red/far-red light-reversible repression of expression of the heterologous oat phy-CAT gene shows that it is regulated by phytochrome in a manner parallel to that of the endogenous rice phy genes. These data indicate that the transduction pathway components and promoter sequences involved in autoregulation of phy expression have been evolutionarily conserved between oat and rice. The experiments show the feasibility of using high-velocity microprojectile-mediated gene transfer for the rapid analysis of light-controlled monocot gene promoters in monocot tissues that until now have been recalcitrant to such studies.