Project description:The silk gland development has a greater impact on silk yields in silkworms. Silk glands from three pure silkworm strains (A798, A306, and XH) with different silk gland weight phenotypes were compared using transcriptome, proteomics, and WGCNA. Five genes (BGIBMGA002524, BGIBMGA002629, BGIBMGA005659, BGIBMGA005711, and BGIBMGA010889) may be strongly associated with the growth of silk glands to be confirmed. These DEGs encoded alkylglycerol monooxygenase (AGMO), glucose dehydrogenase (GDH), zonadhesin (ZAN), odorant binding protein (OBPs), and β-fructofuranosidase (INV), respectively. PCR and ELISA were used to verify the mRNA and protein expression of five genes in the silk glands and tissues of 18 silkworm strains. The GO results showed that four genes have higher levels of expression and participate in glycogen metabolism, fatty acid synthesis, and branched-chain amino acid metabolism, thus, promoting growth and silk proteins synthesis.
Project description:Spider silk synthesis is an emerging model for the evolution of tissue-specific gene expression and the role of gene duplication in functional novelty, but its potential has not been fully realized. Accordingly, we quantified transcript (mRNA) abundance in seven silk gland types and three non-silk gland tissues for three cobweb-weaving spider species. Evolutionary analyses based on expression levels of thousands of homologous transcripts and phylogenetic reconstruction of 605 gene families demonstrated conservation of expression for each gland type among species. Despite serial homology of all silk glands, the expression profiles of the glue-forming aggregate glands were divergent from fiber-forming glands. Also surprising was our finding that shifts in gene expression among silk gland types were not necessarily coupled with gene duplication, even though silk-specific genes belong to multi-paralog gene families. Our results challenge widely accepted models of tissue specialization and significantly advance efforts to replicate silk-based high-performance biomaterials.
Project description:Background: The growth and development of the posterior silk gland and the biosynthesis of the silk core protein at the fifth larval instar stage of Bombyx mori are of paramount importance for silk production. Results: Here, aided by next-generation sequencing and microarry assay, we profile 1,229 microRNAs (miRNAs), including 728 novel miRNAs and 110 miRNA/miRNA* duplexes, from the posterior silk gland at the fifth larval instar. Target gene prediction yields 14,222 unique target genes from 1,195 miRNAs. Functional categorization classifies the genes into complex pathways that include both cellular and metabolic processes, especially protein synthesis and processing. Conclusion: The enrichment of target genes in the ribosome-related pathway indicates that miRNAs may directly regulate translation. Our findings pave a way for further functional elucidation of these miRNAs in silk production.