Project description:Half-smooth tongue sole (Cynoglossus semilaevis) is a commercially valuable flatfish, ranking among the most valuable fishes in the coastal areas of China. It has an asymmetric body shape with lateralization of the eyes to the same side during metamorphosis as same as the other flatfish species. However, little is known about the function and profile of circRNAs in the half-smooth tongue sole. In this study,a total of 2730 circRNAs were identified from in the fish by deep RNA-sequencing technique.
Project description:Half-smooth tongue sole (Cynoglossus semilaevis) is a commercially valuable flatfish, ranking among the most valuable fishes in the coastal areas of China. It has an asymmetric body shape with lateralization of the eyes to the same side during metamorphosis as same as the other flatfish species. However, little is known about the function and profile of lncRNAs in the half-smooth tongue sole. In this study, we carry out a genome-wide review of lncRNAs in the fish by using large-scale deep sequencing.
Project description:Environmental sex determination (ESD) occurs in divergent, phylogenetically unrelated taxa, and in some species co-occurs with genetic sex determination (GSD) mechanisms. Although epigenetic regulation in response to environmental effects has long been proposed to be associated with ESD, a systemic analysis on epigenetic regulation of ESD is still lacking. Using half-smooth tongue sole (Cynoglossus semilaevis) as a model – a marine fish which has both ZW chromosomal GSD and temperature-dependent ESD – we investigated the role of DNA methylation in transition from GSD to ESD by comparing gonadal DNA methylomes of parental females, parental pseudo-males, F1 females, F1 pseudo-males and normal males.
Project description:Environmental sex determination (ESD) occurs in divergent, phylogenetically unrelated taxa, and in some species co-occurs with genetic sex determination (GSD) mechanisms. Although epigenetic regulation in response to environmental effects has long been proposed to be associated with ESD, a systemic analysis on epigenetic regulation of ESD is still lacking. Using half-smooth tongue sole (Cynoglossus semilaevis) as a model – a marine fish which has both ZW chromosomal GSD and temperature-dependent ESD – we investigated the role of DNA methylation in transition from GSD to ESD by comparing gonadal DNA methylomes of parental females, parental pseudo-males, F1 females, F1 pseudo-males and normal males. To assess the gonadal DNA methylome patterns across different sexual types of tongue sole, we carried out BS-seq on bisulfite converted DNA extracted from adult gonads of parental females, parental pseudo-males, and F1 pseudo-males and females from a cross between a parental pseudo-male and a normal female. We also sampled normal male individuals as a control for the normal male DNA methylation pattern. For each of the five samples, two biological replicates were utilized, with each replicate being pooled by five fish. The phenotype and genotype of each selected fish was identified by the histological analysis and PCR validation using the W chromosome specific marker. DNA were isolated from five pooled gonads of the same replicate, then 5 ?g DNA was used to do the bisulfite conversion and BS-seq. The bisulfite conversion of sample DNA was carried out using a modified NH4HSO3-based protocol (Hayatsu et al. 2006). The paired-end library construction and sequencing were carried out using Illumina HiSeq 2000, according to the manufacturer’s instructions (Illumina). We also mixed 25 ng cl857 Sam7 Lambda DNA in each sample to use as conversion quality control for each library.
Project description:Background: Salinity is an important abiotic stress that influences the physiological and metabolic activity, reproduction, growth and development of marine fish. It has been suggested that half-smooth tongue sole (Cynoglossus semilaevis), a euryhaline fish species, use a large amount of energy to maintain osmotic pressure balance when exposed to fluctuations in salinity. To delineate the molecular response of C. semilaevis to different levels of salinity, we performed RNA-seq analysis of the liver to identify the genes and molecular and biological processes involved in responding to salinity change. Results: The present study yielded 330.4 million clean reads, of which 83.9% were successfully mapped to the reference genome of C. semilaevis. One hundred twenty-eight differentially expressed genes (DEGs), including 43 up-regulated genes and 85 down-regulated genes, were identified. These DEGs were highly represented in metabolic pathways, steroid biosynthesis, terpenoid backbone biosynthesis, butanoate metabolism, glycerolipid metabolism and the 2-oxocarboxylic acid metabolism pathway. In addition, genes involved in metabolism, osmoregulation and ion transport, signal transduction, immune response and stress response, cytoskeleton remodeling, and apoptosis were affected during acclimation to low salinity. Genes acat2, fdps, hmgcr, hmgcs1, mvk, pmvk, ebp, lss, dhcr7, and dhcr24 were up-regulated and abat, ddc, acy1 were down-regulated in metabolic pathways. Genes aqp10 and slc6a6 were down-regulated in osmoregulation and ion transport. Genes abat, fdps, hmgcs1, mvk, pmvk and dhcr7 were first reported to be associated with salinity adaptation in teleosts. Conclusions: Our results revealed that metabolic pathways, especially lipid metabolism were important for salinity adaptation. The candidate genes identified from this study provide a basis for further studies to investigate the molecular mechanism of salinity adaptation and transcriptional plasticity in marine fish.