Project description:Heterosis is an important biological phenomenon; however, the role of small RNA (sRNA) in heterosis of hybrid rice remains poorly described. Here, we performed sRNA profiling of F1 super-hybrid rice LYP9 and its parents using high-throughput sequencing technology, and identified 355 distinct mature microRNAs and trans-acting small interfering RNAs, 69 of which were differentially expressed sRNAs (DES) between the hybrid and the mid-parental value. Among these, 34 DES were predicted to target 176 transcripts, of which 112 encoded 94 transcription factors. Further analysis showed that 67.6% of DES expression levels were negatively correlated with their target mRNAs either in flag leaves or panicles. The target genes of DES were significantly enriched in some important biological processes, including the auxin signalling pathway, in which existed a regulatory network mediated by DES and their targets, closely associated with plant growth and development. Overall, 20.8% of DES and their target genes were significantly enriched in quantitative trait loci of small intervals related to important rice agronomic traits including growth vigour, grain yield, and plant architecture, suggesting that the interaction between sRNAs and their targets contributes to the heterotic phenotypes of hybrid rice. Our findings revealed that sRNAs might play important roles in hybrid vigour of super-hybrid rice by regulating their target genes, especially in controlling the auxin signalling pathway. The above finding provides a novel insight into the molecular mechanism of heterosis. We constructed six sRNA sequencing libraries and six mRNA sequencing libraries of flag leaves and panicles of the super-hybrid rice Liangyou-pei9 (LYP9) combination at the grain-filling stage. The above hybrid rice combination includes F1 hybrid LYP9 and its parental lines including the male-sterile line Peiai64s (PA64s) and the restorer line 93-11.
Project description:Heterosis is an important biological phenomenon; however, the role of small RNA (sRNA) in heterosis of hybrid rice remains poorly described. Here, we performed sRNA profiling of F1 super-hybrid rice LYP9 and its parents using high-throughput sequencing technology, and identified 355 distinct mature microRNAs and trans-acting small interfering RNAs, 69 of which were differentially expressed sRNAs (DES) between the hybrid and the mid-parental value. Among these, 34 DES were predicted to target 176 transcripts, of which 112 encoded 94 transcription factors. Further analysis showed that 67.6% of DES expression levels were negatively correlated with their target mRNAs either in flag leaves or panicles. The target genes of DES were significantly enriched in some important biological processes, including the auxin signalling pathway, in which existed a regulatory network mediated by DES and their targets, closely associated with plant growth and development. Overall, 20.8% of DES and their target genes were significantly enriched in quantitative trait loci of small intervals related to important rice agronomic traits including growth vigour, grain yield, and plant architecture, suggesting that the interaction between sRNAs and their targets contributes to the heterotic phenotypes of hybrid rice. Our findings revealed that sRNAs might play important roles in hybrid vigour of super-hybrid rice by regulating their target genes, especially in controlling the auxin signalling pathway. The above finding provides a novel insight into the molecular mechanism of heterosis.
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:The small RNAs presented here were produced as a preliminary exploration of small RNAs in rice, and as such, various tissues and stress conditions were sampled. Small RNAs present in these samples were all mapped to the rice genome TIGR version 5. The total number of distinct mapped sequences are 12879 for Run 1 and 88508 for Run 2. The total number of sequence reads were respectively 70406 and 191682. The datasets contain Oryza sativa var Nipponbar endogenous small RNA sequences in the size range 18 to 34 nt. Plants were grown in a Conviron Environmental Chamber at high light intensity using both high pressure sodium and metal halide lamps for 10.5 hr at 28 degrees C and for 13.5 hr at 26 degrees C in the dark. RNA was extracted from rice tissues at various stages of development and under different abiotic and biotic stresses. The small RNAs presented here were all mapped to the rice genome TIGR version 5. The total number of distinct mapped sequences are 12879 for Run 1 and 88508 for Run 2. The total number of sequence reads were respectively 70406 and 191682.
Project description:Cross-kingdom molecular exchange between hosts and interacting microbes is essential for the survival of both plants and their pathogens. Recent studies showed plants transfer their small RNAs (sRNAs) and massager RNAs (mRNAs) into fungal pathogens to suppress infection. However, whether and how plants send defense proteins into pathogen cells remains unknown. Here, we show that rice plants send defense proteins into the fungal pathogen Rhizoctonia solani via extracellular vesicles (EVs). These vesicles enrich host defense proteins and are taken up by the fungal cells. Reducing EV-mediated host protein transfer leads to increased disease susceptibility. Thus, plants send defense proteins via EVs into fungal pathogens to combat infection, providing a mechanism of protein exchange between plants and pathogens that helps reduce crop disease.
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:MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) regulate gene expression in eukaryotes. Plant miRNAs modulate their targets mainly via messenger RNA (mRNA) cleavage. Small RNA targets have been extensively investigated in Arabidopsis using computational prediction, experimental validation, and degradome sequencing. However, small RNA targets are largely unknown in rice (Oryza sativa). Here, we report global identification of small RNA targets using high throughput degradome sequencing in the rice indica cultivar 93-11 (Oryza sativa L. ssp. indica). 177 transcripts targeted by total of 87 unique miRNAs were identified. Of targets for the conserved miRNAs between Arabidopsis and rice, transcription factors comprise around 70% (58 in 82), indicating that these miRNAs act as masters of gene regulatory nodes in rice. In contrast, non-conserved miRNAs targeted diverse genes which provide more complex regulatory networks. In addition, 5 AUXIN RESPONSE FACTORS (ARF) cleaved by the TAS3 derived ta-siRNAs were also detected. A total of 40 sRNA targets were further validated via RNA ligase-mediated 5’ rapid amplification of cDNA ends (RLM 5’-RACE). Our degradome results present a detailed sRNA-target interaction atlas, which provides a guide for the study of the roles of sRNAs and their targets in rice.
Project description:Here, we present OryzaPG-DB, a rice proteome database based on shotgun proteogenomics, which incorporates the genomic features of experimental shotgun proteomics data. This version of the database was created from the results of 27 nanoLC-MS/MS runs on a hybrid ion trap-orbitrap mass spectrometer, which offers high accuracy for analyzing tryptic digests from undifferentiated cultured rice cells. Peptides were identified by searching the product ion spectra against the protein, cDNA, transcript and genome databases from Michigan State University, and were mapped to the rice genome. Approximately 3200 genes were covered by these peptides and 40 of them contained novel genomic features. Users can search, download or navigate the database per chromosome, gene, protein, cDNA or transcript and download the updated annotations in standard GFF3 format, with visualization in PNG format. In addition, the database scheme of OryzaPG was designed to be generic and can be reused to host similar proteogenomic information for other species. OryzaPG is the first proteogenomics-based database of the rice proteome, providing peptide-based expression profiles, together with the corresponding genomic origin, including the annotation of novelty for each peptide.