Project description:The elucidation of microRNA function and evolution depends on the identification and characterization of miRNA repertoire of strategic organisms, as the fast evolving cichlid fishes. Using RNA-seq and comparative genomics we carried out an in-depth report of miRNAs in Nile tilapia (Oreochromis niloticus). Our results enlarge vertebrate miRNAs collection and reveal a notable differential expression of miRNAs arms and isoforms influenced by sex and developmental life stage, providing a better picture of the evolutionary and spatiotemporal dynamics of miRNAs.
Project description:Cichlids fishes exhibit extensive phenotypic diversification and speciation. In this study we integrate transcriptomic and proteomic signatures from two cichlids species, identify novel open reading frames (nORFs) and perform evolutionary analysis on these nORF regions. We embark comparative transrcriptomics and proteogenomic analysis of two metabolically active tissues, the testes and liver, of two cichlid species Oreochromis niloticus (Nile tilapia, ON) and Pundamilia nyererei (Makobe Island, PN). Our results suggest that the time scale of speciation of the two species can be better explained by the evolutionary divergence of these nORF genomic regions.
Project description:In fish, the sex determining mechanisms can broadly be classified as genotypic (GSD), temperature-dependent (TSD), or genotypic plus temperature effects (GSD+TE). For the fish species with TSD or GSD+TE, extremely high or low temperature can affect its sex determination and differentiation. For long time, the underlying changes in DNA methylation that occur during high or low temperature induced sex reversal have not been fully clarified. In this study, we used Nile tilapia as a model to perform a genome-wide survey of differences in DNA methylation in female and male gonads between control and high temperature induced groups using methylated DNA immunoprecipitation (MeDIP). We identified the high temperature induction-related differentially methylated regions (DMRs), and performed functional enrichment analysis for genes exhibiting DMR. These identified differentially methylated genes were potentially involved in the connection between environmental temperature and sex reversal in Nile tilapia. In this study, four samples (control females, CF; control males, CM; induced females, IF; induced males, IM) were analyzed.
Project description:Triple-negative breast cancer (TNBC) lacks therapeutic target and is difficult to treat. We report a cationic antimicrobial peptide (CAP), tilapia piscidin 4 (TP4), derived from Nile tilapia (Oreochromis niloticus), selectively toxic to TNBC. Here we aim to identify potential target in TNBC cell response to TP4 treatment by microarray study and to further address the role of TP4-resposive genes involved in TNBC cell death.
Project description:Background: The historically recent domestication of fishes has been essential for mankind due to the overexploitation of natural stocks and the increasing protein demand to meet the needs of a growing human population. Selection for relevant traits, such as growth, during domestication is a complex process whose epigenetic basis is poorly understood. Results: We have determined changes that occur in the muscle transcriptome after a single generation of Nile tilapia (Oreochromis niloticus) domestication. There was a downregulation of 2015 genes in fish reared in captivity compared to their wild progenitors. In contrast, several myogenic and metabolic genes that can affect growth potential were upregulated. Methods: RNA was extracted and ribosomal RNA was removed using the Ribo-Zero gold rRNA removal kit. RNA libraries were prepared using the NEBNext Ultra II directional RNA library prep kit for Illumina. In total, we obtained 480 million 150 bp paired-end reads. Conclusion: Taken together, our data indicate that thousands of genes were differentially expressed within a single generation of fish domestication.
