Project description:Rice is a critically important food source but yields worldwide are vulnerable to periods of drought. We exposed eight genotypes of upland and lowland rice (Oryza sativa L. ssp. japonica and indica) to drought stress at the late vegetative stage and harvested leaves for protein extraction and subsequent label-free shotgun proteomics. Gene ontology analysis revealed some differentially expressed proteins were induced by drought in all eight genotypes; we speculate that these play a universal role in drought tolerance. However, some highly genotype-specific patterns of response to drought suggest that some mechanisms of metabolic reprogramming are not universal. Such proteins had largely uncharacterized functions, making them biomarker candidates for drought tolerance screens.
Project description:Purpose: The goal of our study is to compare two different ecotypes of Oryza sativa L., PHS-susceptible rice trait and PHS-resistant rice trait under three different maturation stages in rice seed embryo with profile of miRNA-seq. Methods: Oryza sativa. L miRNA profiles of two different ecotypes with 3 different maturation stages of rice seed embryo were generated by NGS, in duplicate, following Illumina NGS workflow. Results: We found the differentially expressed microRNAs between PHS-susceptible rice trait and PHS-resistant rice trait according to the three different seed maturation stages. Target transcripts of differentially expressed microRNAs have been predicted via psRNATarget web server, and a part of those target genes are likely to be regulated by microRNAs, affecting overall responses to heat stress and the regulation of seed dormancy during maturation. Conclusions: Our study represents the analysis of rice seed small RNAs, specifically microRNAs, under two different ecotypes, three different seed maturation stages in rice seed embryo. Our results show that microRNAs are involved in response to heat stress and the regulation of seed dormancy. This study will provide a foundation for understanding dynamics of seed dormancy during the seed development and overcoming pre-harvest sprouting.
Project description:In order to identify new miRNAs, NAT-siRNAs and possibly abiotic-stress regulated small RNAs in rice, three small RNA libraries were constructed from control rice seedlings and seedlings exposed to drought or salt stress, and then subjected to pyrosequencing.
Project description:Abiotic environmental stresses cause serious economic losses in agriculture. These stresses include temperature extremes, high salinity and drought. To isolate drought-responsive novel coding and noncoding genes, we used the next generation sequencing method from three rice cultivars (wild type nipponbare, nipponbare AP2 transgenic plants, wild type vandana). 36 NGS data of mRNA-seq, small RNA-seq, riboZero-seq were analyzed. For the analyses of these data we constructed a TF-TG (Transcription Factor-Target Gene) network and an ap2 rooted cascading tree. Using these networks and tress we isolated lincRNAs, differentially expressed miRNAs and their targets. We identified several drought stress-related novel/function unknown coding transcripts (transcription factors and functional genes) and non-coding transcripts (small noncoding transcripts such as microRNA and long noncoding transcripts) from these database analyses and have constructed databases of drought stress-related coding and noncoding transcripts Identification of drought-responsive Regulatory Coding and Non-coding Transcripts from rice by deep RNA sequencing
Project description:A biological phenomenon in which hybrids exhibit superior phenotypes from its parental inbred lines known as heterosis, has been widely exploited in plant breeding and extensively used in crop improvement. Hybrid rice has immense potential to increase yield over other rice varieties and hence is crucial in meeting increasing demand of rice globally. Moreover, the molecular basis of heterosis is still not fully understood and hence it becomes imperative to unravel its genetic and molecular basis. In this context, RNA sequencing technology (RNA-Seq) was employed to sequence transcriptomes of two rice hybrids, Ajay and Rajalaxmi, their parental lines, CRMS31A (sterile line, based on WA-CMS) and CRMS32A (sterile line based on Kalinga-CMS) respectively along with the common restorer line of both hybrids, IR-42266-29-3R at two critical rice developmental stages viz., panicle initiation (PI) and grain filling (GF). Identification of differentially expressed genes (DEGs) at PI and GF stages will further pave the way for understanding heterosis. In addition, such kind of study would help in better understanding of heterosis mechanism and genes up-regulated and down-regulated during the critical stages of rice development for higher yield.
Project description:In order to identify new miRNAs, NAT-siRNAs and possibly abiotic-stress regulated small RNAs in rice, three small RNA libraries were constructed from control rice seedlings and seedlings exposed to drought or salt stress, and then subjected to pyrosequencing. Totally three sets of small RNAs, which were obtained under normal condition as well as salt and drought stress conditions
Project description:We aimed to identify differential expression of microRNAs between superior and inferior spikelets by using a deep sequencing approach developed by Solexa (Illumina). Two small RNA libraries were constructed from superior and inferior spikelets at 18 days after fertilization, and more than nine million small RNA sequence reads were generated for each library. Totals of 351 and 312 known miRNAs were obtained from the superior and inferior spikelets, respectively. Analysis of the expression profiles of these miRNAs showed that 189 miRNAs were differentially expressed between superior spikelets and inferior spikelets. In addition, 43 novel miRNAs were identified mostly by the accumulations of miRNA*s were also expressed differentially. Further analysis shows that these miRNAs may individually participate in regulating hormone metabolism, carbohydrate metabolic pathways, and cell division during rice grain development. These results indicate that slow grain filling and low grain weight of rice inferior spikelets probably relation to the expression and function differences between superior and inferior spikelet miRNAs.
Project description:Nitrogen (N), a critical macronutrient for plant growth and development, is a major limiting factor in most agricultural systems. Microarray analyses have been conducted to investigate genome-wide gene expression in response to changes in N concentrations. Although RNA-Seq analysis can provide a more precise determination of transcript levels, it has not previously been employed to investigate the expression of N-starvation-induced genes. We constructed cDNA libraries from leaf sheaths and roots of rice plants grown under N-deficient or -sufficient conditions for 12 h. Sequencing the libraries resulted in identification of 33,782 annotated genes. A comparison of abundances revealed 1,650 transcripts that were differentially expressed (fold-changeââ¥â2) due to an N-deficiency. Among them, 1,158 were differentially expressed in the leaf sheaths (548 up-regulated and 610 down-regulated) and 492 in the roots (276 up, 216 down).