Mechanisms of sex differentiation and sex reversal in hermaphrodite fish as revealed by the Epinephelus coioides genome.

Most grouper species are functional protogynous hermaphrodites, but the genetic basis and the molecular mechanisms underlying the regulation of this unique reproductive strategy remain enigmatic. In this study, we report a high-quality chromosome-level genome assembly of the representative orange-spotted grouper (Epinephelus coioides). No duplication or deletion of sex differentiation-related genes was found in the genome, suggesting that sex development in this grouper may be related to changes in regulatory sequences or environmental factors.

Chromosome-Level Genome Assembly and Transcriptome Comparison Analysis of and Its Related Grouper Species.

The tomato hind, , is a bottom-dwelling coral reef fish, which is widely distributed in the Indo-Pacific and Red Sea. also features complex social structures and behaviour mechanisms. Here, we present a high-quality, chromosome-level genome assembly for that was derived using PacBio sequencing and Hi-C technologies.

Beta-Hydroxysteroid Dehydrogenase Genes in Orange-Spotted Grouper (): Genome-Wide Identification and Expression Analysis During Sex Reversal.

Beta-hydroxysteroid dehydrogenases (β-HSDs) are a group of steroidogenic enzymes that are involved in steroid biosynthesis and metabolism, and play a crucial role in mammalian physiology and development, including sex determination and differentiation. In the present study, a genome-wide analysis identified the numbers of β genes in orange-spotted grouper () (19), human () (22), mouse () (24), chicken () (16), xenopus () (24), coelacanth () (17), spotted gar () (14), zebrafish () (19), fugu () (19), tilapia () (19), medaka () (19), stickleback () (17) and common carp () (27) samples. A comparative analysis revealed that the number of β genes in teleost fish was no greater than in tetrapods due to gene loss followed by a teleost-specific whole-genome duplication event.

Retinoic acid and androgen influence germ cells development and meiotic initiation in juvenile orange-spotted grouper, Epinephelus coioides.

Meiosis is essential for germ cells development for all sexually reproducing species. Retinoic acid (RA) is the key factor controlling the sex-specific timing of meiotic initiation in mammals, birds and tetrapods. Here, we investigated the effects of RA on meiotic initiation and sex determination in protogynous hermaphrodite orange-spotted grouper (Epinephelus coioides).

An SNP-Based Genetic Map and QTL Mapping for Growth Traits in the Red-Spotted Grouper ().

The red-spotted grouper () is one of the most commercially important aquatic species in China. However, its seedstock has low larval survival rates, and its stability is confronted with the danger of overexploitation. In this study, a high-density genetic map was constructed using 3435 single nucleotide polymorphisms (SNPs) from 142 first generation (F) full-sib offspring and two parents of a red-spotted grouper population.

Whole Genome Sequencing of the Giant Grouper () and High-Throughput Screening of Putative Antimicrobial Peptide Genes.

Giant groupers, the largest grouper type in the world, are of economic importance in marine aquaculture for their rapid growth. At the same time, bacterial and viral diseases have become the main threats to the grouper industry. Here, we report a high-quality genome of a giant grouper sequenced by an Illumina HiSeq X-Ten and PacBio Bioscience Sequel platform.

Socially controlled male-to-female sex reversal in the protogynous orange-spotted grouper, Epinephelus coioides.

Socially controlled sex change in teleosts is a dramatic example of adaptive reproductive plasticity. In many cases, the occurrence of sex change is triggered by a change in the social context, such as the disappearance of the dominant individual. The orange-spotted grouper Epinephelus coioides is a typical protogynous hermaphrodite fish that changes sex from female to male and remains male throughout its life span.

Comparative transcriptome analysis of diploid and triploid hybrid groupers (Epinephelus coioides♀ × E. lanceolatus♂) reveals the mechanism of abnormal gonadal development in triploid hybrids.

In our previous studies, diploid and triploid hybrids have been detected from the hybridization of Epinephelus coioides♀ × E. lanceolatus♂. The triploid groupers have been found to be delayed in gonadal development, but the mechanism remains poorly understood.

MT-Feeding-Induced Impermanent Sex Reversal in the Orange-Spotted Grouper during Sex Differentiation.

In this study, we systematically investigated the process of sex reversal induced by 17-methyltestosterone (MT) feeding and MT-feeding withdrawal at the ovary differentiation stage in orange-spotted groupers, . Gonadal histology showed that MT feeding induced a precocious sex reversal from immature ovaries to testes, bypassing the formation of an ovarian cavity, and MT-feeding withdrawal led to an ovarian fate. In both the MT feeding and MT-feeding withdrawal phases, cytochrome P450 family 11 subfamily B () gene expression and serum 11-KT levels were not significantly changed, suggesting that the MT-treated fish did not generate endogenous steroids, even though active spermatogenesis occurred.

Molecular regulation of sex change induced by methyltestosterone -feeding and methyltestosterone -feeding withdrawal in the protogynous orange-spotted grouper.

The sex identity of fish can be easily manipulated by exogenous hormones. Treatment with 17-methyltestosterone (MT) has been widely used to induce a male fate, but the molecular and cellular processes underlying sex changes induced by MT treatments and the withdrawal of MT are not well studied. In this study, we systematically investigated gonadal histology, gene expression profiles, sex steroid hormone levels, and cellular changes during sex changes induced by MT-feeding and MT-feeding withdrawal in the protogynous orange-spotted grouper, Epinephelus coioides.

Transcriptome analysis reveals the molecular mechanisms underlying growth superiority in a novel grouper hybrid (Epinephelus fuscogutatus♀ × E. lanceolatus♂).

Background: Groupers (Epinephelus spp.) have been widely cultivated in China and South-East Asian countries. As a novel hybrid offspring crossed between E.

The complete mitochondrial genome of Epinephelus awoara (Perciformes: Epinephelus) with phylogenetic consideration.

The complete mitochondrial genome of the Epinephelus awoara was presented in this study. The mitochondrial genome is 16 798-bp long and consists of 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region. The gene order and composition of Epinephelus awoara mitochondrial genome was similar to that of most other vertebrates.

The complete mitochondrial genome of the Epinephelus fuscoguttatus (Perciformes: Serranidae).

The complete mitochondrial genome of the Epinephelus fuscoguttatus was presented in this study. The mitochondrial genome is 16,648 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and a control region. The gene order and the composition of E.

Transcriptome analysis of the Trachinotus ovatus: identification of reproduction, growth and immune-related genes and microsatellite markers.

Background: The Trachinotus ovatus (Teleostei, Carangidae) is an economically important marine fish species in the world. However, the lack of genomic information regarding this species limits our understanding of the genetics and biological mechanisms in Trachinotus ovatus. In this study, high throughput transcriptome sequencing was used to obtain comprehensive genomic information in Trachinotus ovatus.

The complete mitochondrial genome of the Epinephelus lanceolatus (Perciformes: Serranidae).

The complete mitochondrial genome of the Epinephelus lanceolatus was presented in this study. The mitochondrial genome is 16,743 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and composition of E.

The complete mitochondrial genome of the Pampus nozawae (Perciformes: Stromateidae).

The complete mitochondrial genome of the Pampus nozawae was presented in this study. The mitochondrial genome is 16,556 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and composition of Pampus nozawae mitochondrial genome was similar to that of most other vertebrates.

The complete mitochondrial genome of the Platax teira (Osteichthyes: Ephippidae).

We presented the complete mitochondrial genome of the Platax teira in this study. The mitochondrial genome is 16,561 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and composition of Epinephelus tukula mitochondrial genome was similar to that of most other vertebrates.