Project description:Genome wide quantitative trait loci (QTL) mapping was conducted in Arabidopsis thaliana using F2 mapping population (Col-0 × Don-0) and SNPs markers. A total of five linkage groups were obtained with number of SNPs varying from 45 to 59 per linkage group. The composite interval mapping detected a total of 36 QTLs for 15 traits and the number of QTLs ranged from one (root length, root dry biomass, cauline leaf width, number of internodes and internode distance) to seven (for bolting days). The range of phenotypic variance explained (PVE) and logarithm of the odds ratio of these 36 QTLs was found be 0.19-38.17% and 3.0-6.26 respectively. Further, the epistatic interaction detected one main effect QTL and four epistatic QTLs. Five major QTLs viz. Qbd.nbri.4.3, Qfd.nbri.4.2, Qrdm.nbri.5.1, Qncl.nbri.2.2, Qtd.nbri.4.1 with PVE > 15.0% might be useful for fine mapping to identify genes associated with respective traits, and also for development of specialized population through marker assisted selection. The identification of additive and dominant effect QTLs and desirable alleles of each of above mentioned traits would also be important for future research.
Project description:Autopolyploidy is a process whereby the chromosome set is multiplied and it is a common phenomenon in angiosperms. Autopolyploidy is thought to be an important evolutionary force that has led to the formation of new plant species. Despite its relevance, the consequences of autopolyploidy in plant metabolism are poorly understood. This study compares the metabolic profiles of natural diploids and artificial autotetraploids of Arabidopsis thaliana Col-0. Different physiological parameters are compared between diploids and autotetraploids using nuclear magnetic resonance (NMR), elemental analysis (carbon:nitrogen balance) and quantitative real-time PCR (qRT-PCR). The main difference between diploid and autotetraploid A. thaliana Col-0 is observed in the concentration of metabolites related to the tricarboxylic acid cycle (TCA) and ?-amino butyric acid (GABA) shunt, as shown by multivariate statistical analysis of NMR spectra. qRT-PCR shows that genes related to the TCA and GABA shunt are also differentially expressed between diploids and autotetraploids following similar trends as their corresponding metabolites. Solid evidence is presented to demonstrate that autopolyploidy influences core plant metabolic processes.
Project description:Cytosine DNA methylation (mC) is a genome modification that can regulate the expression of coding and non-coding genetic elements. However, little is known about the involvement of mC in response to environmental cues. We performed whole genome bisulfite sequencing to assess the spatio-temporal dynamics of mC in Arabidopsis grown under phosphate starvation.
Project description:We obtained an Arabidopsis mutant from the Arabidopsis Biological Resource Center stock collection and verified that it was homozygous for a T-DNA insertion in the first exon of ORRM1 (SALK_072648, designated here as orrm1). The homozygous mutant did not show any phenotypic defect when grown under growth room conditions. We examined the organelle transcriptome of the mutant for editing defects because other proteins carrying RIP domains have been shown to be editing factors. We analyzed the plastid RNA editing extent with a new methodology based on RNA-seq. Briefly, total RNA is isolated from leaves and RT-PCR products corresponding to known organelle genes are obtained by using gene-specific primers. The products are mixed in equimolar ratio, sheared, and used as templates to produce an Illumina TruSeq library. This RNA-seq analysis demonstrated that ORRM1 is a plastid editing factor; 12 among 34 plastid sites exhibit a severe reduction of editing extent in the mutant relative to the wild-type
Project description:New Generation of Artificial MicroRNA and Synthetic Trans-Acting Small Interfering RNA Vectors for Efficient Gene Silencing in Arabidopsis