Project description:MicroRNAs (miRNAs) are small noncoding RNAs that play critical roles in regulating post transcriptional gene expression. Gall midges encompass a large group of insects that are of economic importance and also possess fascinating biological traits. The gall midge Mayetiola destructor, commonly known as the Hessian fly, is a model organism for studying gall midge biology and insect – host plant interactions. In this study, we systematically analyzed miRNAs from the Hessian fly. Deep-sequencing a Hessian fly larval transcriptome led to the identification of 89 miRNA species that are either identical or very similar to known miRNAs from other insects, and 184 novel miRNAs that have not been reported from other species. Microarray analyses revealed the expression of miRNA genes was strictly regulated during Hessian fly larval development and abundance of many miRNA genes were affected by host genotypes. The identification of a large number of miRNAs for the first time from a gall midge provides a foundation for further studies of miRNA functions in gall midge biology and behavior.
Project description:Some insects can redirect plant development to form unique organs called galls, which provide these insects with unique, enhanced food and protection from enemies and the elements. Many galls resemble flowers or fruits, suggesting that elements of reproductive development may be involved. We addressed this possibility using RNA sequencing (RNAseq) to quantify the transcriptional responses of wild grapevine (Vitis riparia Michx.) leaves to a galling parasite, phylloxera (Daktulosphaira vitifoliae (Fitch 1855)). If development of reproductive structures is part of gall formation, we expected to find significantly elevated expression of genes involved in flower and/or fruit development in developing galls as opposed to ungalled leaves. We found that reproductive gene ontology classes were significantly enriched in developing galls, and that expression of many putative genes involved in flower formation was significantly increased, particularly in later gall stages. The patterns of gene expression found in galls suggest that phylloxera exploits vascular cambium to provide meristematic tissue and redirects leaf development towards formation of carpels. The phylloxera leaf gall, and perhaps other similar galls, appears to be phenotypically and transcriptionally convergent on the plant carpel.
Project description:MicroRNAs (miRNAs) are small noncoding RNAs that play critical roles in regulating post transcriptional gene expression. Gall midges encompass a large group of insects that are of economic importance and also possess fascinating biological traits. The gall midge Mayetiola destructor, commonly known as the Hessian fly, is a model organism for studying gall midge biology and insect M-bM-^@M-^S host plant interactions. In this study, we systematically analyzed miRNAs from the Hessian fly. Deep-sequencing a Hessian fly larval transcriptome led to the identification of 89 miRNA species that are either identical or very similar to known miRNAs from other insects, and 184 novel miRNAs that have not been reported from other species. Microarray analyses revealed the expression of miRNA genes was strictly regulated during Hessian fly larval development and abundance of many miRNA genes were affected by host genotypes. The identification of a large number of miRNAs for the first time from a gall midge provides a foundation for further studies of miRNA functions in gall midge biology and behavior. Two wheat lines M-bM-^@M-^\MollyM-bM-^@M-^] and M-bM-^@M-^\NewtonM-bM-^@M-^] were used in the experiment. Newton is a susceptible winter wheat that contains no Hessian fly R gene, and Molly is a nearly isogenic line of Newton, but contains the R gene H13. Larvae were collected one and three days after egg hatch from susceptible Newton and resistant Molly plants. Total RNA extracted from the collected larvae was used for microarray analysis. Three biological replications were used for each treatment and at each time point.
Project description:By sequencing small RNAs from uninfected Arabidopsis roots and from galls seven and 14 days post infection with Meloidogyne incognita, we sequenced by SOLiD technology the RNA fraction below 50nt. We identified 24 miRNAs differentially expressed in gall as putative regulators of gall development.
Project description:All the reports on insect small RNAs come from holometabolous insects. However, small RNAs of hemimetabolous insects have not yet been investigated.Study of hemimetabolous insect small RNAs could provide more insights into evolution and function of small RNAs in hemi- and holometabolous insects. The locust is an important, economically harmful hemimetabolous insect and its phase changes is an interesting phenomenon.Here, we used high-throughput sequencing to characterize and compare the small RNA transcriptomes of gregarious and solitary phases in locusts. We found abundant small RNAs and their different expression profiles in the two phases.