Plastids are the organelles derived from a cyanobacterium through endosymbiosis. Unlike mitochondria, plastids are not found in all eukaryotes, but their evolution has an added layer of complexity since plastids have moved between eukaryotic lineages by secondary and tertiary endosymbiotic events. This complex history, together with the genetic integration between plastids and their host, has l...

A few reports have appeared concerning the synthesis of plastid lipids. Stumpf and James (17) and Stumpf et al. (18) found that both saturated and unsaturated fatty acids may be formed from acetate by chloroplast preparations. However, in some bluegreen algae, Bloch et al. (4) found that long-chain monounsaturates are synthesized by oxidative desaturation of corresponding saturates. Kates (9) s...

Individual plastids of vascular plants have generally been considered to be discrete autonomous entities that do not directly communicate with each other. However, in transgenic plants in which the plastid stroma was labeled with green fluorescent protein (GFP), thin tubular projections emanated from individual plastids and sometimes connected to other plastids. Flow of GFP between interconnect...

Plastid stromules are membrane-bound protrusions of the plastid envelope that contain soluble stroma. Stromules are often found connecting plastids within a cell and fluorescence recovery after photobleaching (FRAP) experiments have demonstrated that green fluorescent protein (GFP) can move between plastids via these connections. In this report, the ability of endogenous plastid proteins to tra...

Here we report the characterization of the Chlamydomonas reinhardtii gene ARG9, encoding the plastid resident N-acetyl ornithine aminotransferase, which is involved in arginine synthesis. Integration of an engineered ARG9 cassette in the plastid chromosome of the nuclear arg9 mutant restores arginine prototrophy. This suggests that ARG9 could be used as a new selectable marker for plastid trans...

BACKGROUND In conventional approaches to plastid and mitochondrial genome sequencing, the sequencing steps are performed separately; thus, plastid DNA (ptDNA) and mitochondrial DNA (mtDNA) should be prepared independently. However, it is difficult to extract pure ptDNA and mtDNA from plant tissue. Following the development of high-throughput sequencing technology, many researchers have attempte...

The discovery of a nonphotosynthetic plastid in malaria and other apicomplexan parasites has sparked a contentious debate about its evolutionary origin. Molecular data have led to conflicting conclusions supporting either its green algal origin or red algal origin, perhaps in common with the plastid of related dinoflagellates. This distinction is critical to our understanding of apicomplexan ev...

The dinoflagellates have repeatedly replaced their ancestral peridinin-plastid by plastids derived from a variety of algal lineages ranging from green algae to diatoms. Here, we have characterized the genome of a dinoflagellate plastid of tertiary origin in order to understand the evolutionary processes that have shaped the organelle since it was acquired as a symbiont cell. To address this, th...

Nicotiana plumbaginifolia protoplasts were directly transformed by PEG treatment with a cloned 16S rRNA gene isolated from a double antibiotic-resistant Nicotiana tabacum plastid mutant. Putative plastid transformants were selected in cell culture by their spectinomycin resistance and identified by their unselected streptomycin resistance. Alternatively, cell lines were selected in the presence...