Lipid accumulation during the establishment of kleptoplasty in Elysia chlorotica.

The establishment of kleptoplasty (retention of "stolen plastids") in the digestive tissue of the sacoglossan Elysia chlorotica Gould was investigated using transmission electron microscopy. Cellular processes occurring during the initial exposure to plastids were observed in laboratory raised animals ranging from 1-14 days post metamorphosis (dpm). These observations revealed an abundance of lipid droplets (LDs) correlating to plastid abundance.

Arabidopsis tic62 trol mutant lacking thylakoid-bound ferredoxin-NADP+ oxidoreductase shows distinct metabolic phenotype.

Ferredoxin-NADP+ oxidoreductase (FNR), functioning in the last step of the photosynthetic electron transfer chain, exists both as a soluble protein in the chloroplast stroma and tightly attached to chloroplast membranes. Surface plasmon resonance assays showed that the two FNR isoforms, LFNR1 and LFNR2, are bound to the thylakoid membrane via the C-terminal domains of Tic62 and TROL proteins in a pH-dependent manner. The tic62 trol double mutants contained a reduced level of FNR, exclusively found in the soluble stroma.

In vivo function of Tic22, a protein import component of the intermembrane space of chloroplasts.

Preprotein import into chloroplasts depends on macromolecular machineries in the outer and inner chloroplast envelope membrane (TOC and TIC). It was suggested that both machineries are interconnected by components of the intermembrane space (IMS). That is, amongst others, Tic22, of which two closely related isoforms exist in Arabidopsis thaliana, namely atTic22-III and atTic22-IV.

Evolution of C4 photosynthesis in the genus Flaveria: how many and which genes does it take to make C4?

Selective pressure exerted by a massive decline in atmospheric CO(2) levels 55 to 40 million years ago promoted the evolution of a novel, highly efficient mode of photosynthetic carbon assimilation known as C(4) photosynthesis. C(4) species have concurrently evolved multiple times in a broad range of plant families, and this multiple and parallel evolution of the complex C(4) trait indicates a common underlying evolutionary mechanism that might be elucidated by comparative analyses of related C(3) and C(4) species. Here, we use mRNA-Seq analysis of five species within the genus Flaveria, ranging from C(3) to C(3)-C(4) intermediate to C(4) species, to quantify the differences in the transcriptomes of closely related plant species with varying degrees of C(4)-associated characteristics.

An mRNA blueprint for C4 photosynthesis derived from comparative transcriptomics of closely related C3 and C4 species.

C(4) photosynthesis involves alterations to the biochemistry, cell biology, and development of leaves. Together, these modifications increase the efficiency of photosynthesis, and despite the apparent complexity of the pathway, it has evolved at least 45 times independently within the angiosperms. To provide insight into the extent to which gene expression is altered between C(3) and C(4) leaves, and to identify candidates associated with the C(4) pathway, we used massively parallel mRNA sequencing of closely related C(3) (Cleome spinosa) and C(4) (Cleome gynandra) species.

Sampling the Arabidopsis transcriptome with massively parallel pyrosequencing.

Massively parallel sequencing of DNA by pyrosequencing technology offers much higher throughput and lower cost than conventional Sanger sequencing. Although extensively used already for sequencing of genomes, relatively few applications of massively parallel pyrosequencing to transcriptome analysis have been reported. To test the ability of this technology to provide unbiased representation of transcripts, we analyzed mRNA from Arabidopsis (Arabidopsis thaliana) seedlings.