Project description:This study aims to identify the differential expression of conserved and novel miRNAs and their target genes in M. oleifera leaf, callus and cold stress treated callus by high-throughput small RNA sequencing.
Project description:Abstract Lysine crotonylation (Kcr) is a recently identified post-translational modification (PTM) in the prokaryotic and eukaryotic organisms. However, the function of lysine-crotonylated proteins in response to abiotic stress in plants remains largely unknown. Here, we report the first global profiling of the Kcr proteome in common wheat, identifying 4,696 Kcr sites on 1,726 substrate proteins, participating in a wide variety of biological and metabolic pathways. Combination of transcriptome and proteome in a RIL (recombinant inbred line) population, Kcr proteome, and genome-wide association study, a candidate gene phosphoglycerate kinase (TaPGK) was identified to potentially affect on cold tolerance in common wheat. Using EMS-mutants, overexpressed transgenic wheat plants and CRISPR/Cas9-mediated know-out mutants, we demonstrated that TaPGK played a positively key role in regulation of plant cold tolerance. Moreover, TaPGK protein strongly interacted with sirtuin-like (TaSRT1). EMS-mutant tetraploid and overexpressed transgenic wheat experiments confirmed that TaSRT1 gene negatively regulated wheat cold tolerance. Immunoprecipitation demonstrated that TaSRT1 promoted the degradation of TaPGK by erasing Kcr. Additionally, RNA-sequencing results showed that overexpressed TaPGK significantly improved expression of peroxidase genes. It concluded that a large number of Kcr sites were present in wheat important proteins and TaPGK crotonylated by TaSRT1 played a key role in wheat response to cold stress through scavenging the accumulation of ROS.
Project description:Stress acclimation is an effective mechanism that plants acquired for adaption to dynamic environmental conditions. After undergoing cold acclimation, plants become more tolerant to cold stress. In order to understand the mechanism of cold acclimation, we performed a systematic, comprehensive study of cold response and acclimation in Cassava (Manihot esculenta), a staple crop and major food source in the tropical regions of the world. We profiled mRNA genes and small-RNA species, using next generation sequencing, and performed an integrative analysis of the transcriptome and microRNAome of Cassava across the normal condition, a moderate cold stress at 14M-BM-0C, a harsh stress at 4M-BM-0C after cold acclimation at 14M-BM-0C, and a cold shock from 24M-BM-0C to 4M-BM-0C. Two results from the analysis were striking. First, the moderate stress and cold shock, despite a difference of 10M-BM-0C between the two, triggered comparable degrees of perturbation to the transcriptome; in contrary, further harsh stress after cold acclimation resulted in a much smaller degree of transcriptome variation. Second and more importantly, about two thirds of the up- or down-regulated genes after moderate stress reversed their expression to down- or up-regulation, respectively, under harsh stress after cold acclimation, resulting in a genome-wide rewiring of regulatory networks. MicroRNAs, which are key post-transcriptional gene regulators, were major players in this massive rewiring of genetic circuitry. Further, a function enrichment analysis of the perturbed genes revealed that cold acclimation helped the plant to develop immunity to further harsh stress by exclusively inducing genes with functions of nutrient reservoir; in contrast, many genes with functions of viral reproduction were induced by cold shock. Our study revealed, for the first time, the molecular basis of stress acclimation in plants, and shed lights on the role of microRNA gene regulation in cold response and acclimation in Euphorbia. Three organs/tissues (folded leaf, fully expanded leaf and roots) of Cassava cultivar SC124 harvested at 6h, 24h and 5d for three cold treatments of CA, CCA and CS, for gene expression profiling at the stages of initial response, secondary response, and functional adaption to cold stresses. Total RNA of each sample was isolated individually, and then pooled with an equal amount from each sample into one for profiling. As a result, four mRNA libraries and four small-RNA libraries, corresponding to the conditions of CA, CCA, CS and NC, were constructed.
Project description:In this study, 17 plants of tetraploid “Zhique” were firstly identified by screening 570 natural seedlings of Citrus wilsonii Tanaka. These tetraploid plants showed different morphology and exhibited significantly increased drought tolerance than the diploids via determination of leaf water potential, relative water content and electrolyte leakage. Large number of genes involved in photosynthesis-responsive were differentially expressed in tetraploids under drought stress by global transcriptome analysis, which was consistent with the detection of photosynthesis indicator including photosynthetic rate, stomatal conductance, chlorophyll and so on. Compared with diploids, phosphorylation modification also plays an important role in the tetraploids after drought stress through the transcriptional and protein level analysis. Additionally, the genes involved in the phenylpropanoid biosynthesis and starch and sucrose metabolism pathways were enriched in both tetraploids and diploids in response to water deficient. Importantly, tetraploids significantly take priority over the diploid via regulating plant hormone signal transduction, especially improving the levels of 3-indoleacetic acid, abscisic acid and salicylic acid and reducing gibberellic A3 and jasmonic acid contents. Collectively, our data reveals that synergistic regulation photosynthesis, phosphorylation modification and plant hormones accumulation contribute to drought tolerance of autotetraploid in Citrus wilsonii.