Project description:The coordination of chloroplast and nuclear genome status are critical for plant cell function, but the mechanism remain largely unclear. In this study, we report that Arabidopsis thaliana CHLOROPLAST AND NUCLEUS DUAL-LOCALIZED PROTEIN 1 (CND1) maintains genome stability in both the chloroplast and the nucleus.
Project description:The coordination of chloroplast and nuclear genome status are critical for plant cell function, but the mechanism remain largely unclear. In this study, we report that Arabidopsis thaliana CHLOROPLAST AND NUCLEUS DUAL-LOCALIZED PROTEIN 1 (CND1) maintains genome stability in both the chloroplast and the nucleus.
Project description:Chloroplast RNA processing requires a large number of nuclear-encoded RNA binding proteins (RBPs) that are imported post-translationally into the organelle. Most of these RBPs are highly specific for one or few target RNAs. By contrast, members of the chloroplast ribonucleoprotein family (cpRNPs) have a wider RNA target range. We here present a quantitative analysis of RNA targets of the cpRNP CP31A using digestion-optimized RNA co-immunoprecipitation with deep sequencing (DO-RIP-seq). This identifies the mRNAs coding for subunits of the chloroplast NDH complex as main targets for CP31A. We demonstrate using whole-genome gene expression analysis and targeted RNA gel blot hybridization that the ndh mRNAs are all down-regulated in cp31a mutants. This diminishes the activity of the NDH complex. Our findings demonstrate how a chloroplast RNA binding protein can combine functionally related RNAs into one post-transcriptional operon.
Project description:Primary objectives: The primary objective is to investigate circulating tumor DNA (ctDNA) via deep sequencing for mutation detection and by whole genome sequencing for copy number analyses before start (baseline) with regorafenib and at defined time points during administration of regorafenib for treatment efficacy in colorectal cancer patients in terms of overall survival (OS).
Primary endpoints: circulating tumor DNA (ctDNA) via deep sequencing for mutation detection and by whole genome sequencing for copy number analyses before start (baseline) with regorafenib and at defined time points during administration of regorafenib for treatment efficacy in colorectal cancer patients in terms of overall survival (OS).
Project description:The regulator for chloroplast biogenesis (rcb) mutant was identified as a mutant defective in phytochrome-mediated chloroplast biogenesis. The rcb mutant has long hypocotyl and albino phenotypes. RCB initiates chloroplast biogenesis in the nucleus by promoting the degradation of the master repressors for chloroplast biogenesis, the PIFs (Phytochrome Interacting Factors). To understand how RCB regulates the expression of PIF-regulated genes, we performed genome-wide expression analysis of RCB-dependent genes using a rcb-10 null allele.
Project description:Deep sequencing provided evidence that a novel subset of small RNAs were derived from the chloroplast genome of Chinese cabbage (Brassica rapa) and Arabidopsis (Ler). The chloroplast small RNAs (csRNAs) include those derived from mRNA, rRNA, tRNA and intergenic RNA. The rRNA-derived csRNA were preferentially located at the 3â-ends of the rRNAs, while the tRNA-derived csRNAs were mainly located at 5â-termini of the tRNAs. After heat treatment, the abundance of csRNAs decreased in chinese cabbage seedlings, except those of 24 nt in length. The novel heat-responsive csRNAs and their locations in the chloroplast were verified by Northern blotting. The regulation of some csRNAs to the putative target genes were identified by real-time PCR. Our results indicated that high temperature regulated the production of some csRNAs, which may have potential roles in transcriptional or post-transcriptional regulation, and affected putative target genes expression in chloroplast.
