title: Olive: a key gene required for chlorophyll biosynthesis in Antirrhinum majus.
abstract: Olive (oli) is a recessive nuclear mutation of Antirrhinum majus which reduces the level of chlorophyll pigmentation and affects the ultrastructure of chloroplasts. The oli-605 allele carries a Tam3 transposon insertion which has allowed the locus to be isolated. The oli gene encodes a large putative protein of 153 kDa which shows homology to the products of two bacterial genes necessary for tetrapyrrole-metal chelation during the synthesis of bacteriochlorophyll or cobyrinic acid. We therefore propose that the product of the oli gene is necessary for a key step of chlorophyll synthesis: the chelation of magnesium by protoporphyrin IX. Somatic reversion of the oli-605 allele produces chimeric plants which indicate that the oli gene functions cell-autonomously. Expression of oli is restricted to photosynthetic cells and repressed by light, suggesting that it may be involved in regulating the rate of chlorophyll synthesis in green tissues.
authors.affiliation: Institute of Cell and Molecular Biology, University of Edinburgh, UK.
authors.forename: A
authors.initials: A
authors.lastname: Hudson
authors.forename: R
authors.initials: R
authors.lastname: Carpenter
authors.forename: S
authors.initials: S
authors.lastname: Doyle
authors.forename: E S
authors.initials: ES
authors.lastname: Coen
mesh_terms: D000595:Amino Acid Sequence; D015152:Blotting, Northern; D002734:Chlorophyll / Q000096:biosynthesis / Q000235:genetics*; D002736:Chloroplasts; D003001:Cloning, Molecular; D017343:Genes, Plant; D008969:Molecular Sequence Data; D015394:Molecular Structure; D016254:Mutagenesis, Insertional; D010641:Phenotype; D010944:Plants / Q000235:genetics*; D015183:Restriction Mapping; D017386:Sequence Homology, Amino Acid
chemical_list: D002734:Chlorophyll