Project description:This trial was undertaken to examine the perhipheral cellular and antibody response of cattle following infestation with the cattle tick, Rhipicephalus microplus. The information from the Affymetrix gene expression data is used to complement other measurements of immune function such as cellular subset composition and antibody response in cattle of high (Brahman) and low (Holstein-Friesian) resistance to the cattle tick. Experiment Overall Design: RNA was extracted from white blood cells during a period of successive, heavy infestations with R. microplus. RNA samples from 3 Holstein-Friesian and 3 Brahman animals were analysed on individual slides.
Project description:Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and B. taurus cattle Global analysis of gene expression changes in R. microplus during larval, pre-attachment and early adult stages of its life cycle feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13 601 R. microplus transcripts from BmiGI Version 2 we identified 297 up and 17 down regulated transcripts were differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman)] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian)]. These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor and cuticle. Microarrays were validated by qRT-PCR analysis of selected transcripts including the validation of three housekeeping genes. The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases, and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds particularly Bos indicus cattle.
Project description:This experiment was undertaken to document changes in gene expression in the skin of tick-resistant Brahman (Bos indicus) and tick-susceptible Holstein-Friesian (Bos taurus) cattle prior to, and following, infestation with the cattle tick Rhipicephalus (Boophilus) microplus Experiment Overall Design: RNA was extracted from skin samples of tick-naïve cattle (animals with no previous R.microplus exposure) and tick-infested cattle after a period of successive, heavy infestations with R. microplus. Skin samples taken from tick-infested animals were taken at sites where tick larvae (approximately 24 h old) were attached to the skin sample. Skin samples were of 8 mm diameter and full skin thickness (approximately 10 mm). RNA samples from 12 animals (3 tick-naive Holstein-Friesian, 3 tick-naive Brahman, 3 tick-infested Holstein-Friesian and 3 tick-infested Brahman) were processed and hybridised to individual slides.
Project description:To understand the effect of Babesia infection on Rhipicephalus microplus hemocyte gene expression, we performed high throughput RNA-sequencing using samples collected from Rhipicephalus microplus uninfected tick hemolymph and infected with either Babesia bigemina or Babesia bovis. We evaluated gene expression differences that may be attributed to tick immune defense to babesial infection.
Project description:Comparative microarray analysis of Rhipicephalus (Boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on Bos indicus and B. taurus cattle Global analysis of gene expression changes in R. microplus during larval, pre-attachment and early adult stages of its life cycle feeding on Bos indicus and Bos taurus cattle were compared using gene expression microarray analysis. Among the 13 601 R. microplus transcripts from BmiGI Version 2 we identified 297 up and 17 down regulated transcripts were differentially expressed between R. microplus feeding on tick resistant cattle [Bos indicus (Brahman)] compared to R. microplus feeding on tick susceptible cattle [Bos taurus (Holstein-Friesian)]. These include genes encoding enzymes involved in primary metabolism, and genes related to stress, defence, cell wall modification, cellular signaling, receptor and cuticle. Microarrays were validated by qRT-PCR analysis of selected transcripts including the validation of three housekeeping genes. The analysis of all tick stages under survey suggested a coordinated regulation of defence proteins, proteases, and protease inhibitors to achieve successful attachment and survival of R. microplus on different host breeds particularly Bos indicus cattle. The microarray was conducted by NimbleGen Systems Inc following the method reported by Saldivar [Saldivar L et al., Insect Mol Biol 2008, 17(6):597-606]. 10 samples: 2 larva, 2 pre-attachment larva in B. indicus and 2 in B. taurus, and 2 adult ticks in B. indicus and 2 in B. taurus
Project description:Transcriptional profiling of midgut tissues isolated from Rhipicephalus microplus and Rhipicephalus decoloratus females at day 20 post infestation. This enabled the identification of transcripts that are species-specific or shared between the two tick species tested.
Project description:A R. microplus microarray was used to study differential gene expression in acaricide exposed larvae from an amitraz-resistant strain. The acaricide treatments were: organophosphate (OP), pyrethroid, ivermectin, and amitraz. The microarrays contained over 13,000 probes corresponding to each member of R. microplus gene index ESTs previously described (http://compbio.dfci.harvard.edu/tgi/cgi-bin/tgi/gimain.pl?gudb=b_microplus). Serial analysis of gene expression (SAGE) data from the OP treated R. microplus was used to verify the OP microarray data. The expression profiles of selected transcripts were verified by real time PCR. Among the significantly differentially expressed genes, were a tick legumain, involved in blood digestion, gluthathione S-transferase (GST), a detoxification enzyme involved in pesticide resistance, acyltransferase, several putative salivary sulfotransferases, and a glutamate receptor. **Note: contact person: Felix D. Guerrero email: felix.guerrero@ars.usda.gov Keywords: Rhipicephalus (Boophilus) microplus, acaricide resistance genes, organophosphates OP, microarrays, detoxification enzymes.
Project description:Study of tick cells from the Rhipicephalus microplus vector (BME/CTVM6) were infceted by SFTS virus at MOI of 1 PFU/cell. We collected samples at day 3 and 6 post-infection, and added the mock infected control. This was done in 4 replicates, and allow us to perform a proteomics informed by transcriptomic study, as well as differentially protein expression analysis.
Project description:With regulatory roles in development, cell proliferation and disease, micro-RNA (miRNA) biology is of great importance and a potential key to novel RNA-based therapeutic regimens. Biochemically based sequencing approaches have provided robust means of uncovering miRNA binding landscapes on transcriptomes of various species. However, a current limitation to the therapeutic potential of miRNA biology in cattle is the lack of validated miRNAs targets. Here, we use cross-linking immunoprecipitation (CLIP) of the Argonaute (AGO) proteins and unambiguous miRNA-target identification through RNA chimeras to define a regulatory map of miRNA interactions in the cow (Bos taurus). The resulting interactome is the deepest reported to date for any species, demonstrating that comprehensive maps can be empirically obtained. We observe that bovine miRNA targeting principles are consistent with those observed in other mammals. Motif and structural analyses define expanded pairing rules with most interactions combining seed-based pairing with distinct, miRNA-specific patterns of auxiliary pairing. Further, miRNA-target chimeras had predictive value in evaluating true regulatory sites of the miR-17 family. Finally, we define miRNA-specific targeting for >5000 mRNAs and determine gene ontologies (GO) for these targets. This confirmed repression of genes important for embryonic development and cell cycle progress by the let-7 family, and repression of those involved in cell cycle arrest by the miR-17 family, but it also suggested a number of unappreciated miRNA functions. Our results provide a significant resource for transcriptomic understanding of bovine miRNA regulation, and demonstrate the power of experimental methods for establishing comprehensive interaction maps.