Project description:Bombyx mori nucleopolyhedrovirus (BmNPV) is one of the most acute infectious diseases in silkworm, which has caused great economic loss in sericulture. Previous study showed that the content of components in mulberry leaves, particularly for moracin N, was increased after UV-B irradiation. In this study, the BmNPV resistance of silkworms reared on UV-B treated and moracin N spreaded mulberry leaves was improved. To uncover the mechanism of enhanced BmNPV resistance, silkworm midguts from UV-B treated mulberry leaves (BUM) and moracin N (BNM) groups were analyzed by SWATH-based proteomic technique. Of note, the abundance of ribosomal proteins in BUM and BNM groups was significantly changed to maintain the synthesis of total protein levels and cell survival. While, cytochrome c oxidase subunit II, calcium ATPase and programmed cell death 4 involved in apoptotic process were up-regulated in BNM group. Expressions of lipase-1, serine protease precursor, Rab1 protein, and histone genes were increased significantly in BNM group. These results suggest that moracin N might be the main active components in UV-B treated mulberry leaves to affect the BmNPV-resistance of silkworm, which could promote apoptotic cell death, enhance the organism immunity, and regulate the intercellular environment of cells in silkworm. It also presents an innovative process to reduce the mortality rate of silkworm infected with BmNPV.
Project description:To characterize the role of the ERI-6/7 helicase in endogenous small RNA pathways in C. elegans, small RNA populations from null alleles of eri-6 and eri-7, and from mutants of known endogenous RNAi pathway factors, eri-1 and ergo-1, were determined by deep sequencing, and compared to wild type.
Project description:Background. Silkworm pupae (SWP) is the main by-product of the sericulture industry with an interesting nutritional profile, especially in terms of proteins. In consideration of its possible use as a food or food ingredient in Western countries, a comparative proteomic experiment has been performed to investigate the differences of the protein profile of male and female SWP reared on mulberry leaves or on an artificial diet. Methods. The nutritional profile of lyophilized SWP in terms of dry matter and ash was evaluated according to the AOAC procedures, the total nitrogen content was determined by a nitrogen analyzer and the SWP gross energy value was measured using an adiabatic calorimetric bomb. The comparative proteomic analysis was performed on male and female SWP reared on mulberry leaves or on the artificial diet. Proteins were separated by Bidimensional Electrophoresis (2DE) and, after a multivariate statistical analysis, the differentially expressed proteins were identified by LC-MS/MS. Results. The comparative proteomic approach highlighted 47 SWP proteins differentially expressed comparing diet and gender. PCA analysis showed that 7 proteins were more effective in discriminating the sex and 5 were more effective in discriminating the diet type. In spite of the above mentioned differences in the SWP protein profile, no strong alteration of the pupa physiological traits have been demonstrated, suggesting a general SWP flexibility to adapt to a well-balanced artificial diet. Differences in lipid transport and metabolism were found among the experimental groups, that might have a relevant effect on the timing, on hormone secretion and, in turn, on insect voltinism. This aspect may also affect silk production, as univoltine strains are the most productive. Although this is a preliminary study, the proteomic data may offer a contribution in understanding also the influence of gender and farming strategy on the allergen profile of B. mori, when used as food or as a food ingredient. Since female silkworm pupae reared on mulberry leaves seemed to contain lower levels of known allergens than those reared in the other experimental conditions, we speculated that these findings may help when farming B. mori for food production purposes. However, these results need to be supported by further characterization of the allergenic potential of B. mori.
Project description:To characterize the role of the ERI-6/7 helicase in endogenous small RNA pathways in C. elegans, small RNA populations from null alleles of eri-6 and eri-7, and from mutants of known endogenous RNAi pathway factors, eri-1 and ergo-1, were determined by deep sequencing, and compared to wild type. Small RNA analysis in wild type and eri-1, ergo-1, eri-6 and eri-7 mutant C. elegans strains.
Project description:ERI-6/7 is a negative regulator of exogenous RNAi, however the function of SOSI-1 has never previously been characterized. We noticed that expression of sosi-1 and eri-6/7 are mutually exclusive. Due to its genomic locus being nested within the eri-6 locus, we hypothesized that sosi-1 could be acting as a regulator of ERI-6/7 function by disrupting eri-6/7 expression upon sensing changes in the production of MUT-16-dependent 22G siRNAs. Our data confirms that expression of the sosi-1 mRNA is regulated by MUT-16-dependent 22G siRNAs. In addition, we show here that the expression of the eri-6 and eri-7 pre-mRNAs, and thus the eri-6/7 trans-spliced mRNA, are mis-regulated upon loss of sosi-1-targeting and eri-6[e-f]-targeting MUT-16-dependent 22G siRNAs, suggesting that sosi-1 and eri-6[e-f] act as a feedback sensor for small RNA function.
Project description:Small RNAs (21-24 nt) are pivotal regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in diverse eukaryotes, including most if not all plants. MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are the two major types, both of which have a demonstrated and important role in plant development, stress responses and pathogen resistance. In this work, we used a deep sequencing approach (Sequencing-By-Synthesis, or SBS) to develop sequence resources of small RNAs from different Carica papaya tissues (including leaves and flowers). The high depth of the resulting datasets enabled us to examine in detail critical small RNA features, such as size distribution, tissue-specific regulation and sequence conservation between different organs in this species. We also developed database resources and a dedicated website (http://smallrna.udel.edu/) with computational tools for allowing other users to identify new miRNAs or siRNAs involved in specific regulatory pathways, verify the degree of conservation of these sequences in other plant species and map small RNAs on genes or larger regions of the maize genome under study. Small RNA libraries were derived from leaves, virus-infected leaves and female flowers of Carica papaya. Total RNA was isolated using the TriReagent (Molecular Research Center) and submitted to Illumina (Hayward, CA, http://www.illumina.com) for small RNA library construction using approaches described in (Lu et al., 2007) with minor modifications. The small RNA libraries were sequenced with the Sequencing-By-Synthesis (SBS) technology by Illumina. PERL scripts were designed to remove the adapter sequences and determine the abundance of each distinct small RNA. We thank Ray Ming and Qingyi Yu for providing the plant material, as well as Kan Nobuta and Gayathri Mahalingam for assistance with the computational methods.
Project description:Background: Papaya (Carica papaya L.) is a commercially important crop that produces climacteric fruits with a soft and sweet pulp that contain a wide range of health promoting phytochemicals. Despite its importance, little is known about transcriptional modifications during fruit ripening and its control. In this study we report the analysis of ripe papaya transcriptome by using a cross-species (XSpecies) microarray technique based on the phylogenetic proximity between papaya and Arabidopsis thaliana. Results: Papaya transcriptome analyses resulted in the identification of 414 ripening-related genes and some of them had their expression validated by qPCR. The transcription profile was then compared with that from ripening tomato and grape. Overall, the transcriptomics analysis revealed many similarities between ripening in papaya and tomato especially with respect to primary metabolism, regulation of transcription, biotic and abiotic stress and cell wall metabolism. XSpecies microarray data indicate that transcription factors (TFs) of the MADS-box, NAC and AP2/ERF gene families are involved in the control of papaya ripening and reveal that cell wall-related gene expression in papaya showed similarities to the expression profiles seen in A. thaliana during hypocotyl development. Conclusion: The cross-species array experiment was successful in identifying ripening-related genes in papaya. The data indicated common and diverse elements of transcription control between fruit bearing taxa and has also indicated a possible distinct co-evolutionary mechanism for papaya cell wall disassembling system. The present study represents new topics for future researches that would help complement the structural genomic data provided by the papaya genome, since there is no gene-chip available for this plant organism. Papaya ripe transcriptome was analysed using mRNA extracted from unripe and ripe fruit from 2 replicates. After microarray hybridization in ATH1-121501 chip, data were normalized against data generated by papaya DNA hybridization in another ATH1-121501 chip and analysed using perl algorithms (masks).
Project description:The freeze-thaw awakening is a method in which seeds or germ cells prior to germination are slowly cooled, stored, and thawed to promote growth. To further test the validity of this method, we applied freeze-thaw awakening treatment on papaya seeds. When the seed was grown under room temperature (15-25C), the germination rate increased by more than 40% compared to those that were not subjected to the method. At 60 days post germination, the plant’s height was about 1.4 times as high as that of the untreated control. In addition, when both samples were grown in the field for about a year and a half, the treated showed darker green leaf color and an increase of seedlings per seed compared to the control. No significant difference in weight per fruit was observed. Comprehensive gene expression analysis of papaya leaves using RNA-seq showed more than 1000 differentially expressed genes, of which had genes involved in plant hormone synthase and environmental stress response. From these results, we show here that freeze-thaw-awakening is an effective method in promoting papaya growth.