MicroRNAs(miRNAs)are important regulators of nearly all aspects of biological processes in eukaryotes.During the biogenesis of miRNAs,the RNase III enzyme Dicer processes double-strand precursor miRNAs into mature miR...MicroRNAs(miRNAs)are important regulators of nearly all aspects of biological processes in eukaryotes.During the biogenesis of miRNAs,the RNase III enzyme Dicer processes double-strand precursor miRNAs into mature miRNAs and promotes the assembly of RNA-induced silencing complexes(RISCs).Dicer has been reported to participate in a wide range of physiological processes,including development and immunity,in some insect species.However,the physiological roles of Dicer in lepidopterans remain poorly understood.In this study,we investigated the function of Bombyx mori Dicer1.We first performed sequence alignment and found that the sequence of functional domains of Dicer1 are varied among Lepidoptera,Diptera,Coleoptera,Blattaria,and Orthoptera.Using a binary clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 genome editing approach,we showed that BmDicer1 mutants have arrested development from the 3rd instar into the 4th instar.RNA sequencing analysis indicated that the defects in BmDicer1 mutants are due to dysregulation of genes that encode proteins involved in metabolism,protein degradation,absorption,and renin–angiotensin pathways.Analysis using quantitative real-time polymerase chain reaction showed that mutation of BmDicer1 altered expression of miRNAs and their target genes.Therefore,our study demonstrates the critical roles of BmDicer1 in miRNA biogenesis and larval development in silkworm.展开更多
U1 small nuclear ribonucleoproteins(U1 snRNP)associates with 5ʹsplice sites in the form of ribonucleoprotein particles and is highly conserved among species.The physiological functions of U1 snRNP in a lepidopteran mo...U1 small nuclear ribonucleoproteins(U1 snRNP)associates with 5ʹsplice sites in the form of ribonucleoprotein particles and is highly conserved among species.The physiological functions of U1 snRNP in a lepidopteran model insect Bombyx mori is mostly unknown.Here,we showed that U1 snRNP plays an important role in the development of silkworm.Knockout of U1 snRNP in silkworm showed either delayed or stationary 1st instar larva development compared with the wild-type group.U1 snRNP deletion mutants exhibited abnormal cellular phenotypes with enlarged cell nucleus,scant cytoplasm and enlarged nuclei.RNA-seq analysis revealed that genes involved in metabolic pathway,biosynthesis of secondary metabolites and steroid hormone biosynthesis were significantly affected by U1 snRNP depletion.Taken together,our study suggests that U1 snRNP homeostasis plays an important role in silkworm development.展开更多
基金supported by grants from National Natural Science Foundation of China(31830093,32100381).The funders had no role in study design,data collection and analysis,decision to publish,or preparation of the manuscript.
文摘MicroRNAs(miRNAs)are important regulators of nearly all aspects of biological processes in eukaryotes.During the biogenesis of miRNAs,the RNase III enzyme Dicer processes double-strand precursor miRNAs into mature miRNAs and promotes the assembly of RNA-induced silencing complexes(RISCs).Dicer has been reported to participate in a wide range of physiological processes,including development and immunity,in some insect species.However,the physiological roles of Dicer in lepidopterans remain poorly understood.In this study,we investigated the function of Bombyx mori Dicer1.We first performed sequence alignment and found that the sequence of functional domains of Dicer1 are varied among Lepidoptera,Diptera,Coleoptera,Blattaria,and Orthoptera.Using a binary clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9 genome editing approach,we showed that BmDicer1 mutants have arrested development from the 3rd instar into the 4th instar.RNA sequencing analysis indicated that the defects in BmDicer1 mutants are due to dysregulation of genes that encode proteins involved in metabolism,protein degradation,absorption,and renin–angiotensin pathways.Analysis using quantitative real-time polymerase chain reaction showed that mutation of BmDicer1 altered expression of miRNAs and their target genes.Therefore,our study demonstrates the critical roles of BmDicer1 in miRNA biogenesis and larval development in silkworm.
基金supported by grants from the National Science Foundation of China(31830093,32021001 and 31802005)Strategic Priority Research Program of Chinese Academy of Sciences(XDB11010600).
文摘U1 small nuclear ribonucleoproteins(U1 snRNP)associates with 5ʹsplice sites in the form of ribonucleoprotein particles and is highly conserved among species.The physiological functions of U1 snRNP in a lepidopteran model insect Bombyx mori is mostly unknown.Here,we showed that U1 snRNP plays an important role in the development of silkworm.Knockout of U1 snRNP in silkworm showed either delayed or stationary 1st instar larva development compared with the wild-type group.U1 snRNP deletion mutants exhibited abnormal cellular phenotypes with enlarged cell nucleus,scant cytoplasm and enlarged nuclei.RNA-seq analysis revealed that genes involved in metabolic pathway,biosynthesis of secondary metabolites and steroid hormone biosynthesis were significantly affected by U1 snRNP depletion.Taken together,our study suggests that U1 snRNP homeostasis plays an important role in silkworm development.