AT_CHLORO (www.grenoble.prabi.fr/at_chloro) is a database dedicated to sub-plastidial localization of A. thaliana chloroplast proteins. This information was infered from proteomics experiments obtained from a comprehensive study that allowed the identification of proteins from envelope, stroma, and thylakoid sub-compartments Ferro et al., 2010. In addition to current knowledge regarding sub-pla...

Two well-known pathways for the degradation of chloroplast proteins are via autophagy and senescence-associated vacuoles. Here, we describe a third pathway that was activated by senescence- and abiotic stress-induced expression of Arabidopsis thaliana CV (for chloroplast vesiculation). After targeting to the chloroplast, CV destabilized the chloroplast, inducing the formation of vesicles. CV-co...

Phototropin is the blue-light receptor that mediates phototropism, chloroplast movement, and stomatal opening in Arabidopsis. Blue and red light induce chloroplast movement in the moss Physcomitrella patens. To study the photoreceptors for chloroplast movement in P. patens, four phototropin genes (PHOTA1, PHOTA2, PHOTB1, and PHOTB2) were isolated by screening cDNA libraries. These genes were cl...

Here, we describe the snowy cotyledon3 (sco3-1) mutation, which impairs chloroplast and etioplast development in Arabidopsis thaliana seedlings. SCO3 is a member of a largely uncharacterized protein family unique to the plant kingdom. The sco3-1 mutation alters chloroplast morphology and development, reduces chlorophyll accumulation, impairs thylakoid formation and photosynthesis in seedlings, ...

The single chloroplast of the alga Chlamydomonas reinhardtii contains at least 100 copies of the chloroplast chromosome. It is not known how the chloroplast (or cell) becomes homoplasmic for a mutation that arises in one of these copies. Under suitable selection conditions, clones with chloroplast mutations for streptomycin resistance induced by methyl methanesulfonate can be recovered with dir...

Blue-light-induced chloroplast photorelocation movement is observed in most land plants. Chloroplasts move toward weak-light-irradiated areas to efficiently absorb light (the accumulation response) and escape from strong-light-irradiated areas to avoid photodamage (the avoidance response). The plant-specific kinase phototropin (phot) is the blue-light receptor for chloroplast movements. Althoug...

Dihydrostreptomycin binds preferentially to chloroplast ribosomes of wild-type Euglena gracilis Klebs var. bacillaris Pringsheim. The K(diss) for the wild-type chloroplast ribosome-dihydrostreptomycin complex is 2 x 10(-7) M, a value comparable with that found for the Escherichia coli ribosome-dihydrostreptomycin complex. Chloroplast ribosomes isolated from the streptomycin-resistant mutant Sm(...

Photosynthetic eukaryotes have evolved an elaborate system of nuclear-chloroplast interdependence to ensure the coordinate regulation of photosynthesis and other cellular processes. One of the most dramatic consequences of the evolution of the chloroplast from original prokaryotic endosymbiont to a cellular organelle has been the transfer of the vast majority of genes encoding chloroplast polyp...

Dear Editor, What does the evolutionary origin of a plant protein tell about its subcellular localization? Naively thinking, one would assume that plant proteins that were originally encoded in the endosymbiont genome are targeted to the chloroplast. However, published data seem to support only a loose link between evolutionary origin and subcellular localization. About half of the Arabidopsis ...

Chloroplasts and their nonphotosynthetic relatives in the plastid organelle family evolved from a cyanobacterial endosymbiont (for review, see Timmis et al., 2004). The subsequent coevolution of the chloroplast and nuclear genomes produced an organelle that is eubacterial at its core but with extensive chloroplastspecific embellishments. Of the thousands of genes in the cyanobacterial ancestor,...