Project description:Bienertia sinuspersici performs C4 photosynthesis without Kranz anatomy through subcellular compartmentalization of carbon fixation within individual cells. In this species, central compartment chloroplasts (C) and peripheral chloroplasts (P) collaborate with cytosolic and mitochondrial components in a NAD-ME type C4 cycle. How the two functionally different chloroplast types can develop within individual cells and the mechanism of import of nuclear encoded, plastid targeted proteins are currently unknown. We used 454 sequencing in combination with large scale label-free proteomics to determine the distribution of photosynthesis-related proteins. Subcellular localization of 169 protein was determined through comparison of protein abundance in four different subcellular fractions. 39 out of the 120 chloroplastic proteins showed differential accumulation between the two chloroplast types. Rubisco, RPP regenerative phase and PSII related proteins accumulated in C chloroplasts whereas C4 related proteins and the NDH complex were more abundant in P chloroplasts. Comparison of transit peptides of differential accumulating proteins indicated no obvious sequence homology or similarities in physico-chemical properties between members of the same group. Protein composition analysis of the central compartment indicated that mitochondria and peroxisomes are the only major components besides chloroplasts in this compartment. The combined information from subcellular and developmental protein profiling was used to generate a first draft of the protein machinery involved in single-cell C4 photosynthesis.
Project description:Bienertia sinuspersici performs C4 photosynthesis without Kranz anatomy through subcellular compartmentalization of carbon fixation within individual cells. In this species, central compartment chloroplasts (C) and peripheral chloroplasts (P) collaborate with cytosolic and mitochondrial components in a NAD-ME type C4 cycle. How the two functionally different chloroplast types can develop within individual cells and the mechanism of import of nuclear encoded, plastid targeted proteins are currently unknown. We used 454 sequencing in combination with large scale label-free proteomics to determine the distribution of photosynthesis-related proteins. Subcellular localization of 169 protein was determined through comparison of protein abundance in four different subcellular fractions. 39 out of the 120 chloroplastic proteins showed differential accumulation between the two chloroplast types. Rubisco, RPP regenerative phase and PSII related proteins accumulated in C chloroplasts whereas C4 related proteins and the NDH complex were more abundant in P chloroplasts. Comparison of transit peptides of differential accumulating proteins indicated no obvious sequence homology or similarities in physico-chemical properties between members of the same group. Protein composition analysis of the central compartment indicated that mitochondria and peroxisomes are the only major components besides chloroplasts in this compartment. The combined information from subcellular and developmental protein profiling was used to generate a first draft of the protein machinery involved in single-cell C4 photosynthesis.
Project description:The Bienertia sinuspersici chloroplast whole genome (cpDNA) sequencing was completed in this study. Bienertia sinuspersici chloroplast genome is 153,472?bp in length and contains 127 genes, such as 83 unique protein-coding genes, 36 tRNA genes and eight rRNA genes. There were two inverted repeat regions (IR) and small and large single-copy regions (SSC and LSC) with 24,948?bp, 19,016 and 84,560?bp, respectively. 59% of the B. sinuspersici cpDNA consisted of gene-coding regions (protein-coding and RNA genes). The overall GC contents of the B. sinuspersici cpDNA were 36.59% and in the LSC, SSC and IR regions were 34.47%, 29.42% and 42.94%, respectively. A phylogenetic analysis of seven complete cpDNA from Chenopodiaceae family shows that B. sinuspersici cpDNA is closely related to Salicornia species.