Project description:Parallel Analysis of RNA Ends (PARE) sequencing reads were generated to validate putative microRNAs and identify cleavage sites in Sorghum bicolor and Setaria viridis.
Project description:A total of 18 libraries from Setaria viridis were constructed using the Illumina TruSeq sample preparation method. We used two biological replicate libraries from the leaf, whole panicles (inside leaf sheath), whole panicles (coming out of leaf sheath), whole panicles (completely out of leaf sheath), whole panicles (completely out of leaf sheath, after pollination), spikelet (inside leaf sheath), spikelet (coming out of leaf sheath), and spikelet (completely out of leaf sheath).
Project description:RNA-seq was performed to profile the transcriptomes of inflorescence primordia hand-dissected from the bristleless1-1 (bsl1-1)mutant in Setaria viridis compared to wild-type controls sampled under the same conditions. Bsl1 encodes a rate limiting enzyme in BR biosynthesis, which is the ortholog of D11 from rice. Mutants are characterized by a homeotic conversion of sterile bristles to spikelets in the inflorescence.
Project description:Setaria viridis is a small, rapidly growing grass species in the subfamily Panicoideae, a group that includes economically important cereal crops such as maize and sorghum. The S. viridis inflorescence displays complex branching patterns, but its early development is similar to that of other panicoid grasses, and thus is an ideal model for studying inflorescence architecture. Here we report detailed transcriptional resource that captures dynamic transitions across six sequential stages of S. viridis inflorescence development, from reproductive onset to floral organ differentiation. Co-expression analyses identified stage-specific signatures of development, which include homologs of previously known developmental genes from maize and rice, suites of transcription factors and gene family members, and genes of unknown function. This spatiotemporal co-expression map and associated analyses provide a foundation for gene discovery in S. viridis inflorescence development, and a comparative model for exploring related architectural features in agronomically important cereals.
Project description:Setaria viridis (green millet) is gaining popularity as a model C4 monocot due to its small size, rapid life cycle, and compact, sequenced genome. To analyze the structure and regulation of genes throughout development, the transcriptomes of 13 tissues at different stages of development were determined by RNA sequencing, and transcription start sites were mapped. Genes were identified that are differentially expressed in different developmental stages within the leaf, as well as in the apical meristem before and after the transition from vegetative to reproductive growth, and in panicles before and after anthesis. In a majority of genes, transcription initiated at the sequence YR within a narrow peak 20 – 40 nt downstream of a TATA box. Genes expressed in multiple tissues generally use the same transcription start site across all tissue types. Several introns were identified that increase gene expression. These results will increase understanding of plant development, improve the annotation of the Setaria genome, and provide tissue-specific or constitutive promoters for use in transgenic applications.
Project description:Inflorescence architecture in cereal crops directly impacts yield potential through regulation of seed number and harvesting ability. Extensive architectural diversity found in inflorescences of grass species is due to spatial and temporal activity and determinacy of meristems, which control the number and arrangement of branches and flowers, and underlie plasticity. Timing of the floral transition is also intimately associated with inflorescence development and architecture. Here, we show that a single mutation in a gene encoding an AP1 A-class MADS-box transcription factor significantly delays flowering time and disrupts multiple levels of meristem determinacy in panicles of the C4 model panicoid grass, Setaria viridis.
Project description:Our recently published results demonstrated a crucial role for plastid terminal oxidase (PTOX) as an alternative electron pathway in the halophyte Spartina alterniflora (S. alterniflora) under salt stress but not for the glycophyte Setaria viridis (S. viridis). Herein, the effect of salt on the photosynthetic electron transport and RNA-seq analysis was probed in Setaria and its salt-tolerant close relative S. alterniflora. Initially, plants were grown at soil then were salt-treated under hydroponic conditions for two weeks. Setaria shows high vulnerability to salt compared to Spartina; while, Setaria was unable to survive exposure to greater than 100 mM, Spartina could tolerate salt concentrations as high as 550 mM with merely negligible effect on gas exchange and conductance of electrons transport chain (gETC). After exposure to salt, the prompt fluorescence (OJIP-curves) reveals an increase in the O- and J-steps in Setaria and very less or no change for SA. This suggests a higher QA over-reduction in Setaria than in Spartina. Following salt treatment, a dramatic decline in PSII primary photochemistry for Setaria was observed, as displayed by the drastic drop in Fv/Fm, Fv/Fo and ΦPSII. However, no substantial change was recorded regarding these parameters for Spartina under NaCl treatment. Interestingly, we report an improvement in primary PSII photochemistry (ΦPSII) for Spartina with increasing either salt concentration or duration. Besides, the magnitude of NPQ dynamics was strongly enhanced for Setaria even at low NaCl level (50 mM); however, it remains unchangeable or slightly increased for Spartina at high NaCl concentrations (above 400 mM). For plants endured salt, we notice an increase in both the proportion of oxidized P700 and the amount of active P700 in Setaria and almost no change for Spartina. The slowdown of electrons flow through PSII was accompanied by a dramatic decline in gETC. Under salt, CO2 assimilation (A) and stomatal conductance (gs) evaluations demonstrate that A decreases earlier, even after one week exposure to only 50 mM NaCl for Setaria; however, the effect of salt was negligible in Spartina regarding these two parameters even after exposure for two weeks to high salt levels (400 and 550 mM). For Setaria exposed for 12 d to salt, the use of 2,000 μmol m-2 s-1 external CO2 was not sufficient to fully restore A to the control level as assessed by A-Ci curves, even for 50 mM salt. The A at all NaCl levels, except 550 mM, was able to completely recover to initial level before stress in Spartina. RNAseq analysis shows a stimulation of oxido-reduction reactions in Setaria. Gene onthology (GO) enrichment emphasizes differentially expressed genes (DEGs) and some transcription factors (TFs) under salt. The up-regulated genes in Setaria are related to three metabolic processes; C4, photorespiration and the oxidation/reduction pathways. Some other specifically highly up-regulated genes in Setaria are mostly related to TFs including DNA-binding transcription factor activity, stress marker genes such as peroxidase and senescence-related genes such as flavonol synthase.