Transcriptome analysis of the Nile tilapia (Oreochromis niloticus) reveals altered expression of immune genes by cadmium.

Nile tilapia (Oreochromis niloticus) is a worldwide farmed fish and has been widely used for the study on comparative immunology in teleosts. It is well known that cadmium (Cd) can cause a variety of adverse effects in fish. However, data on the effects of Cd in fish liver and the defensive mechanisms of these effects using transcriptome approach are relatively scarce to date.

Combined effects of copper and cadmium exposure on ovarian function and structure in Nile Tilapia (Oreochromis niloticus).

With the rapid development of industrialization and urbanization, the issue of copper (Cu) and cadmium (Cd) pollution in aquatic ecosystems has become increasingly severe, posing threats to the ovarian tissue and reproductive capacity of aquatic organisms. However, the combined effects of Cu and Cd on the ovarian development of fish and other aquatic species remain unclear. In this study, female Nile tilapia (Oreochromis niloticus) were individually or co-exposed to Cu and/or Cd in water.

Effects of four hormones on the mitigation of ovarian damage in tilapia (Oreochromis niloticus) after copper and cadmium exposure.

Female tilapia of the Genetic Improvement of Farmed Tilapia (GIFT) strain were selected as an animal model to study the effects of four hormonal drugs in mitigating ovarian damage following exposure to copper and cadmium. After combined exposure to copper and cadmium in aqueous phase for 30 d, tilapia were randomly injected with oestradiol (E2), human chorionic gonadotropin (HCG), luteinizing hormone releasing hormone (LHRH), or coumestrol and raised in clear water for 7 d Ovarian samples were collected after combined exposure to heavy metals for 30 d and after recovery for 7 d Gonadosomatic index (GSI), copper and cadmium levels in the ovary, reproductive hormone levels in serum, and mRNA expression of key reproductive regulatory factors were determined. After 30 d of exposure to the combined copper and cadmium in aqueous phase, the Cd content in tilapia ovarian tissue increased by 1,242.

Transcriptomics integrated with metabolomics reveals the effect of Lycium barbarum polysaccharide on apoptosis in Nile tilapia (Oreochromis niloticus).

Lycium barbarum polysaccharide (LBP) is one of the main active ingredients in the fruit of L. barbarum L. It has been used as herbal medicine for thousands of years in China.

Integrative ATAC-seq and RNA-seq Analysis of the Longissimus Muscle of Luchuan and Duroc Pigs.

Luchuan pig is a typical obese pig breed in China, and the diameter and area of its longissimus dorsi muscle fibers are significantly smaller than those of Duroc (lean) pig. Skeletal muscle fiber characteristics are related to meat quality of livestock. There is a significant correlation between the quality of different breeds of pork and the characteristics of muscle fiber, which is an important factor affecting the quality of pork.

Metabolism and antioxidation regulation of total flavanones from Sedum sarmentosum Bunge against high-fat diet-induced fatty liver disease in Nile tilapia (Oreochromis niloticus).

Diet-induced fatty liver is a considerable threaten to fish aquaculture due to the popularity of the high-fat diet (HFD) feeding. Our study aims to investigate the effects of flavanones from Sedum sarmentosum Bunge (FSSB) on the liver function to identify a potential treatment for HFD-induced fatty liver disease. Physiological and pathological indicators were tested in the liver of Nile tilapia (Oreochromis niloticus) and results showed parameters including lipid metabolites, redox parameters, and inflammatory factors could be adequately restored to normal level by addition of 150 mg/kg FSSB to HFD.

Low expression of miR-19a-5p is associated with high mRNA expression of diacylglycerol O-acyltransferase 2 (DGAT2) in hybrid tilapia.

DGAT2 (acyl CoA:diacylglycerol acyltransferase 2) is a key and rate-limiting enzyme that catalyzes the final step of triglyceride (TG) synthesis. In this study, hybrid tilapia were generated from Nile tilapia (♀) and blue tilapia (♂) crossing. The TG content levels in the liver of these tilapia were measured.

Effects of Lycium barbarum polysaccharides on immunological parameters, apoptosis, and growth performance of Nile tilapia (Oreochromis niloticus).

In this study, the effect of Lycium barbarum polysaccharides (LBP) on immunological parameters, apoptosis, and growth performance of Nile tilapia (Oreochromis niloticus) was investigated. Dietary supplementation with LBP significantly increased complement 3 (C3) activity and promoted interleukin IL-1β gene expression in spleen tissue, significantly reduced apoptosis in spleen tissue, increased the specific growth rate (SGR), relative length gain (LG), and relative weight gain (WG) of Nile tilapia. However, dietary supplementation with LBP did not have a significant effect on serum alkaline phosphatase (AKP), malondialdehyde (MDA), and superoxide dismutase (SOD), blood constituents, apoptosis, or gene expression of IL-1β in liver tissue.

Nonadditive and Asymmetric Allelic Expression of Growth Hormone in Hybrid Tilapia.

Hybridization is a common breeding technique that can improve germplasm through heterosis in aquaculture. However, the regulation of key gene expression, including the details of transcriptional level changes at the beginning of hybridization events, remains largely undefined, especially in teleosts. In this study, by interspecies crossing between two pure lines of Nile tilapia and blue tilapia, we obtained a hybrid tilapia population as a model to elucidate heterosis, and we traced the molecular outcomes of growth hormone (GH) expression and allele-specific expression (ASE) in hybrids.

Transcriptome Analysis of Ovary Development in Nile Tilapia Under Different Photoperiod Regimes.

This study investigated the molecular mechanisms involved in ovarian transcriptomic responses in Nile tilapia under different photoperiod regimes. Histological analysis indicated that ovarian development was significantly affected by photoperiod. The photoperiods tested were as follows: LD (12 h light:12 h dark), LL (24 h light:0 h dark), and DD (0 h light:24 h dark).

DNA methylation of pituitary growth hormone is involved in male growth superiority of Nile tilapia (Oreochromis niloticus).

Growth hormone (GH) and its receptors are critical regulators of somatic growth and metabolism. It has been shown in mammals that the methylation of cytosines within the GH promoter plays a key role in regulating transcripts expression. In the present study, the GH, GHR1 and GHR2 proximal promoters were identified and the methylation levels of these genes in corresponding tissues were assayed.

Identification and characterization of microRNAs in ovary and testis of Nile tilapia (Oreochromis niloticus) by using solexa sequencing technology.

MicroRNAs (miRNAs) are endogenous non-coding small RNAs which play important roles in the regulation of gene expression by cleaving or inhibiting the translation of target gene transcripts. Thereinto, some specific miRNAs show regulatory activities in gonad development via translational control. In order to further understand the role of miRNA-mediated posttranscriptional regulation in Nile tilapia (Oreochromis niloticus) ovary and testis, two small RNA libraries of Nile tilapia were sequenced by Solexa small RNA deep sequencing methods.

Molecular cloning of vasa gene and the effects of LHRH-A on its expression in blue tilapia Oreochromis aureus.

The full length of vasa cDNA in blue tilapia Oreochromis aureus was cloned and sequenced using reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). Nucleotide sequence analysis revealed that the cDNA contained 2,143 bp and was consisted of a 48-bp 5' untranslated terminal region (5'-UTR), a 157-bp 3' untranslated terminal region (3'-UTR) and a 1,938-bp open reading frame (ORF) which encoded 645 amino acids. Homological protein analysis showed that vasa in O.