Project description:Background: Skewing root patterns provide key insights into root growth strategies and mechanism that produce root architectures Roots exhibit skewing and waving when grown on a tilted, impenetrable surface, and while the genetics guiding these morphologies have been examined, the underlying molecular mechanisms of skewing and waving remain unclear. In this study, transcriptome data were derived from two Arabidopsis ecotypes, WS and Col-0, under three tilted growth conditions in order to identify candidate genes involved in skewing. WS is a skewing ecotype. Col-0 is a non-skewing ecotype. Results: This work identifies a number of genes that are likely involved in skewing, using growth conditions that differentially affect skewing and waving. Comparing the gene expression profiles of WS and Col-0 in different tilted growth conditions identified 11 candidate genes as potentially involved in the control of skewing. These 11 genes are involved in several different cellular processes, including sugar transport, salt signaling, cell wall organization, and hormone signaling. Conclusions: Many of the 11 identified genes are involved in signaling and perception, rather than the physical restructuring of roots, leading to the conclusion that root skewing is enabled through diverse environmental signaling pathways. These findings revealed further insights into the molecular mechanisms behind root skewing. This work investigated the transcriptional differences between skewing and non-skewing roots. Comparisons within WS revealed gees that that responded to the angle of growth (Agp) during the process of skewing. These genes were cross referenced with transcripts differing between the WS and Col-0 genotypes to refine the list of genes that are most probably be involved in root skewing. More of the highly probable skew gene candidates (HPSGC) are associated with environmental sensing (e.g. salt, sugar, hormones, darkness) than with physical growth differences (e.g. cell wall remodeling, cell division, cell elongation). Thus, the root behavior of skewing appears to be primarily driven by pathways that respond to disparate signals from the root local environment. Future studies could investigate the HPSGC to find the specific pathways and molecular mechanisms contributing to root skewing.
Project description:The goal of this project is to compare the primary metabolite profile in different tissue types of the model plant Arabidopsis thaliana. Specifically, plants were grown hydroponically under the long-day (16hr light/day) condition at 21C. Tissue samples, including leaves, inflorescences, and roots were harvest 4 1/2 weeks post sowing. Untargeted primary metabolites profiling was carried out using GCTOF.
Project description:The growth behavior of plant roots on tilted, hard agar surfaces is determined by many basic cellular processes, including microtubule dynamics and cell wall expansion. Among Arabidopsis thaliana accessions there is natural variation for these behaviors, including one known as skewing or slanting. The root skewing pattern on hard, tilted agar surfaces may be a clue to adaptations of an accession to its environment. Here, we compare expression profiles of two accessions with diverse skewing behavior grown on the wave assay, which consists of seedlings growing two days vertically and 3 days tilted on hard agar plates. Cvi has a strong skew on tilted, hard agar sufaces, and Ler-2 has a weaker one. We also include a near isogenic line, 170G-55-16 a.k.a HGI2.1, that is mostly Ler-2 in background but has a segment of Cvi introgressed into chromosome 2. This line has an intermediate skew between its two parents.
Project description:The growth behavior of plant roots on tilted, hard agar surfaces is determined by many basic cellular processes, including microtubule dynamics and cell wall expansion. Among Arabidopsis thaliana accessions there is natural variation for these behaviors, including one known as skewing or slanting. The root skewing pattern on hard, tilted agar surfaces may be a clue to adaptations of an accession to its environment. Here, we compare expression profiles of two accessions with diverse skewing behavior grown on the wave assay, which consists of seedlings growing two days vertically and 3 days tilted on hard agar plates. Cvi has a strong skew on tilted, hard agar sufaces, and Ler-2 has a weaker one. We also include a near isogenic line, 170G-55-16 a.k.a HGI2.1, that is mostly Ler-2 in background but has a segment of Cvi introgressed into chromosome 2. This line has an intermediate skew between its two parents. 3 biological replicates of each of 3 genotypes (Cvi, Ler-2, and 170G-55-16/HGI2.1) were subjected to the wave assay. After the assay, approximately 600 root tips from each biological replicate were pooled for RNA extraction and hybridization on the Affymetrix ATH1 microarray.