Project description:We applied high throughput sequencing technology to identify microRNA genes in bighead carp and silver carp. We identified 167 conserved miRNAs in bighead carp and 166 in silver carp. By two computational stragegies, we obtained 39 novel miRNAs in bighead carp and 54 in silver carp, for which, no homologs were found in other species. Several miRNA* sequences were found in our dataset as well, some particular ones might have gene regulation function. Gain and loss of family members were observed in several miRNA families, which partially reflected the fate of miRNA gene duplicates.
Project description:Common carp is one of the main commercial fishes captured and cultured worldwide. Although common carp genome is not finished yet, this study provides a first large scale cloning and characterization of common carp miRNAs and their potential targets. These miRNAs add to the growing database of new miRNA and lay the foundation for further understanding of miRNA function in gene regulation of common carp.
Project description:Because fin base is supposed to be the entry zone of some fish virus, we wanted to know which transcripts are induced after infection of zebrafish with Spring Viremia Carp Virus (SVCV). Two days after infection, differentially expressed transcript levels from selected immune-related zebrafish genes were studied in zebrafish fins. Also transcripts from resistant fishes to viral infection one month after inoculation were studied.
Project description:Whilst the hybrids of F1 generations usually experience heterosis for fitness-related traits (including the resistance to parasites), post-F1 generations, due to Dobzhansky–Muller genetic incompatibilities, express numerous disadvantageous traits (including susceptibility to parasites). Genetic disruption in hybrids may also result from the broken system of cyto-nuclear coadaptation. Maternal backcrosses (each parent having with the same mtDNA of parents) and paternal backcrosses (each parent having with different mtDNA of parents) have the same nuclear genetic compositions, but differ in cytoplasmic genetic elements, affecting their viability and survival. Spring viraemia of the carp virus (SVCV), a disease with a serious economic impact in aquacultures, affects almost exclusively cyprinids, primarily common carp, and causes high mortality, whilst gibel carp is a less susceptible species. Our study was focused on the transcriptome profile analysis of head kidney to reveal differential gene expression in highly susceptible common carp, weakly susceptible gibel carp, and hybrid lines, hypothetizing that the patterns of differential gene expression will reflect hybrid heterosis in F1 generations and hybrid breakdown in backcrosses and F2 generations. We expected the differences in differential gene expression between maternal and paternal backcrosses to be in line with the hypothesis of broken cyto-nuclear coadaptation.
Project description:We applied high throughput sequencing technology to identify microRNA genes in bighead carp and silver carp. We identified 167 conserved miRNAs in bighead carp and 166 in silver carp. By two computational stragegies, we obtained 39 novel miRNAs in bighead carp and 54 in silver carp, for which, no homologs were found in other species. Several miRNA* sequences were found in our dataset as well, some particular ones might have gene regulation function. Gain and loss of family members were observed in several miRNA families, which partially reflected the fate of miRNA gene duplicates. Total RNA of juvenile bighead carp and silver carp were sequenced on one Solexa lane, respectively.
Project description:Cyprinid herpesvirus 3 (CyHV-3), also known as koi herpesvirus (KHV), is the aetiological agent of an emerging and lethal disease in common and koi carp. In this work we studied the immune response of two genetically different lines of common carp (Polish K and Polish R3) infected with CyHV-3 by immersion. The two carp lines presented a 20% difference in survival rate and, furthermore, significant difference in virus loads measured at day 3 post infection (p.i.). Microarray analysis revealed that 581 genes in line K (330 up-regulated, 251 down-regulated) and 107 genes in line R3 (77 up-regulated, 30 down-regulated), were at least 2-fold differentially expressed at day 3 p.i. compared to day 0. Genes which were at least 4-fold differentially expressed in both lines were selected as potential markers of an infection of common carp by CyHV-3. This group includes 17 up-regulated and only 1 down-regulated genes. In addition, microarray analysis revealed no significant differences in gene expression between line K and R3 at day 0. At day 3 p.i. there were, however, 76 genes that were at least 2-fold differentially expressed between the two lines. The kinetics of expression of T cell markers and selected cytokines indicate for higher activation of immune response in more resistant R3 line. Thus, our study revealed that differences in resistance to CyHV-3 between two carp lines can be correlated with differentially expressed immune-related genes. The experiment included four biological replicates with no dye swaps for (i) each strain (K and R3) and (ii) each condition (day 0 and day 3).
Project description:We describe here transcripts induced after infection of zebrafish with Spring Viremia Carp Virus (SVCV). Two days after infection, differentially expressed transcript levels from selected immune-related zebrafish genes were studied in internal organs (pooled spleen, head kidney). Also, transcripts from resistant fishes to viral infection one month after inoculation were studied.
Project description:Cyprinid herpesvirus 3 (CyHV-3), also known as koi herpesvirus (KHV), is the aetiological agent of an emerging and lethal disease in common and koi carp. In this work we studied the immune response of two genetically different lines of common carp (Polish K and Polish R3) infected with CyHV-3 by immersion. The two carp lines presented a 20% difference in survival rate and, furthermore, significant difference in virus loads measured at day 3 post infection (p.i.). Microarray analysis revealed that 581 genes in line K (330 up-regulated, 251 down-regulated) and 107 genes in line R3 (77 up-regulated, 30 down-regulated), were at least 2-fold differentially expressed at day 3 p.i. compared to day 0. Genes which were at least 4-fold differentially expressed in both lines were selected as potential markers of an infection of common carp by CyHV-3. This group includes 17 up-regulated and only 1 down-regulated genes. In addition, microarray analysis revealed no significant differences in gene expression between line K and R3 at day 0. At day 3 p.i. there were, however, 76 genes that were at least 2-fold differentially expressed between the two lines. The kinetics of expression of T cell markers and selected cytokines indicate for higher activation of immune response in more resistant R3 line. Thus, our study revealed that differences in resistance to CyHV-3 between two carp lines can be correlated with differentially expressed immune-related genes.
Project description:The biological impact of microRNAs is determined by their targets, and robustly identifying direct miRNA targets remains challenging. Existing methods suffer from high false-positive rates and are unable to effectively differentiate direct miRNA targets from downstream regulatory changes. Here, we present a simple approach to deconvolute post-transcriptional and transcriptional changes using PRO-seq with RNA-seq. In combination, these methods allow us to systematically profile the regulatory impact of a miRNA. We refer to this approach as CARP: Combined Analysis of RNA-seq and PRO-seq. We apply CARP to multiple miRNAs and show that it robustly distinguishes direct targets from downstream changes, while greatly reducing false positives. We validate our approach using Argonaute eCLIP-seq and ribosome profiling, demonstrating that CARP defines a comprehensive repertoire of targets. We identify miRNA-specific activity of target sites within the coding region. CARP facilitates the dissection of complex changes in gene regulatory networks triggered by miRNAs and identification of transcription factors that underlie downstream regulatory changes. Given the robustness of the approach, CARP is particularly suitable for dissecting miRNA regulatory networks in vivo.