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:Several reports have described the involvement of miRNAs in abiotic stresses. However, their role in biotic stress or to beneficial microbes has not been fully explored. In order to understand on the epigenetic regulation in plant in response to nitrogen-fixing bacteria association, we analyzed the sRNA regulation in maize hybrids (Zea mays M-bM-^@M-^S UENF 506-8) inoculated with the beneficial diazotrophic bacteria (Herbaspirillum seropedicae). Deep sequencing analysis was carried out to identify the sRNAs regulated in maize during association with diazotrophic bacteria. For this analysis, maize plants were germinated in wet paper and put in hydroponic system with HoaglandM-bM-^@M-^Ys solution and then inoculated with H. seropedicae for seven days. Mock and inoculated plants were collected and total RNA from a pool of samples was extracted with Trizol reagent. The two sRNA libraries were sequenced by Illumina. The sequences were filtered to remove adaptors and contaminants rRNA and tRNAs, and sequences with 18-28 nt in length were selected. To identify the miRNAs present in these libraries, we used two strategies using the same website (http://srna-tools.cmp.uea.ac.uk): one to identify novel miRNAs using the maize genome (verson 2) and miRCat pipeline; and other to identify conserved miRNAs using the miRBase database (release 13.0, http://microrna.sanger.ac.uk) and miRProf pipeline. We identified 17 novel putative miRNAs candidates and mapped the precursor of these miRNAs in the maize genome. Furthermore, we identified 25 conserved miRNAs families and the differential expressions were analyzed with miRProf pipeline. The bioinformatics analysis of four up-regulated miRNAs (miR397, miR398, miR408 and miR528) in inoculated plant was validated using stemM-bM-^@M-^Sloop RT-PCR assay. Our findings contribute to increase the knowledge of the molecular relation between plants and endophytic bacteria. Screenning of sRNA transcriptome of maize plants inoculated with Herbaspirillum seropedicae after seven days
Project description:Several reports have described the involvement of miRNAs in abiotic stresses. However, their role in biotic stress or to beneficial microbes has not been fully explored. In order to understand on the epigenetic regulation in plant in response to nitrogen-fixing bacteria association, we analyzed the sRNA regulation in maize hybrids (Zea mays – UENF 506-8) inoculated with the beneficial diazotrophic bacteria (Herbaspirillum seropedicae). Deep sequencing analysis was carried out to identify the sRNAs regulated in maize during association with diazotrophic bacteria. For this analysis, maize plants were germinated in wet paper and put in hydroponic system with Hoagland’s solution and then inoculated with H. seropedicae for seven days. Mock and inoculated plants were collected and total RNA from a pool of samples was extracted with Trizol reagent. The two sRNA libraries were sequenced by Illumina. The sequences were filtered to remove adaptors and contaminants rRNA and tRNAs, and sequences with 18-28 nt in length were selected. To identify the miRNAs present in these libraries, we used two strategies using the same website (http://srna-tools.cmp.uea.ac.uk): one to identify novel miRNAs using the maize genome (verson 2) and miRCat pipeline; and other to identify conserved miRNAs using the miRBase database (release 13.0, http://microrna.sanger.ac.uk) and miRProf pipeline. We identified 17 novel putative miRNAs candidates and mapped the precursor of these miRNAs in the maize genome. Furthermore, we identified 25 conserved miRNAs families and the differential expressions were analyzed with miRProf pipeline. The bioinformatics analysis of four up-regulated miRNAs (miR397, miR398, miR408 and miR528) in inoculated plant was validated using stem–loop RT-PCR assay. Our findings contribute to increase the knowledge of the molecular relation between plants and endophytic bacteria.
Project description:Sugarcane plantlets from a variety with high inputs of N obtained from BNF (genotype SP70-1143, CTC, Brazil) free of microorganisms were obtained by sterile meristem culture and micropropagation according to the method of Hendre et al. (1983). In vitro-grown SP70-1143 rooted sugarcane plantlets were inoculated as described by James et al. (1994) with 0.1 ml of 106–107 bacterial suspension. Controls were inoculated with medium only. Endophytic diazotrophic bacteria used were Gluconacetobacter diazotrophicus (PAL5 strain) or a mixture of Herbaspirillum seropedicae (HRC54 strain) and H. rubrisubalbicans (HCC103 strain). All plants were maintained at 30°C with an irradiance of 60 µmol photons m–2 s–1 for 12 h d–1. One day after the inoculation, plant tissues were examined for bacterial colonization by the Most Probable Number (MPN) estimation, according to the methods of Reis et al. (1994) and plantlets were collected and immediately frozen in liquid nitrogen. Five plantlets were polled for each treatment. Extraction of total RNA was performed separately on each sample pool. Keywords: comparison of associations with different endophytic bacterias
Project description:Endophytic bacteria influence plant growth and development and therefore are an attractive resource for applications in agriculture. However, little is known about the impact of these microorganisms on secondary metabolite (SM) production by medicinal plants. Here we assessed, for the first time, the effects of root endophytic bacteria on the modulation of SMs in the medicinal plant Lithospermum officinale (Boraginaceae family), with a focus on the naphthoquinones alkannin/shikonin (A/S). The study was conducted using a newly developed in vitro system as well as in the greenhouse. Targeted and non-targeted metabolomics approaches were used and supported by expression analysis of the gene PGT, encoding a key enzyme in the A/S biosynthesis pathway. Three bacterial strains, Chitinophaga sp. R-73072, Xanthomonas sp. R-73098 and Pseudomonas sp. R-71838 induced a significant increase of diverse SMs, including A/S, in L. officinale in both systems, demonstrating the strength of our approach for screening A/S derivative-inducing bacteria. Our results highlight the impact of root-endophytic bacteria on secondary metabolism in plants and indicate that production of A/S derivatives in planta likely involves cross-modulation of different metabolic pathways that can be manipulated by bacterial endophytes.