Continuous labelling of callus with H-thymidine results in intermittent peaks of H-DNA per chloroplast, showing synchrony of division. The increase in H-DNA could be due to several replication rounds, and the drop to successive plastid divisions without intervening DNA synthesis. The level of DNA-binding proteins in the chloroplast parallels the peaks of plastidal DNA synthesis; such pro...

An in vivo test system was developed to study group II intron splicing in higher plant chloroplasts. The chimeric reporter gene uidA was constructed by translational fusion of an intron-containing segment of the plastid atpF gene with the coding region of a plastid uidA reporter gene. The chimeric uidA gene was inserted into the tobacco plastid genome by the biolistic transformation procedure u...

Advances in Plastid Biology and Its Applications Plastids originated from endosymbiosis around 1.5 billion years ago. They have been extensively studied to understand photosynthesis and other metabolic functions and to express foreign proteins, and knowledge about plastids has greatly increased. However, there are many aspects of plastid biology that remain unclear, and there have been difficul...

The ability to manipulate plant fatty acid biosynthesis by using new biotechnological approaches has allowed the production of transgenic plants with unusual fatty acid profile and increased oil content. This review focuses on the production of very long chain polyunsaturated fatty acids (VLCPUFAs) and the increase in oil content in plants using molecular biology tools. Evidences suggest that r...

Knowledge on plant genomes has progressed during the past few years. Two plant genomes, those of Arabidopsis thaliana and rice, have been sequenced. Our present knowledge of synteny also indicates that, despite plasticity contributing to the diversity of the plant genomes, the organization of genes is conserved within large sections of chromosomes. In parallel, novel plant transformation system...

T ransgene containment is a central concern in genetically modified (GM) crops, especially for those with out-crossing wild relatives. However, plant cells contain genomes in the nucleus, mitochondria, and chloroplasts. Whereas nuclear genes are biparentally inherited, organelle genes are in general maternally inherited (1, 2). Therefore, engineering foreign genes in the chloroplast genome may ...

The leaf mosaic of Abutilon sellovianum is caused by abutilon mosaic virus (AbMV), a geminivirus that has a circular single-stranded DNA genome. DNA was isolated from intact plastids of AbMV-infected and noninfected plants. Plastids from infected plants were shown to contain the single-stranded AbMV DNA by Southern-blot hybridization experiments that used a probe made from highly purified AbMV ...