Expressions of melanopsins in telencephalon imply their function in synchronizing semilunar spawning rhythm in the mudskipper Boleophthalmus pectinirostris.

The mudskipper Boleophthalmus pectinirostris inhabits intertidal mudflats, exhibiting semilunar reproductive rhythms. To investigate whether melanopsin is possibly involved in the synchronization of the semilunar spawning rhythm in the female mudskipper, we first cloned all four melanopsin subtypes (opn4m1, opn4m3, opn4x1, opn4x2) in B. pectinirostris.

GFP expression pattern in pituitary and gonads under the control of nuclear progesterone receptor promoter in transgenic zebrafish.

Background: The nuclear progesterone receptor (Pgr) is a ligand-dependent transcription factor primarily responsible for mediating progesterone actions relevant for reproduction across vertebrates. Information on the cellular localization of Pgr expression in the reproductive system is required for developing a comprehensive approach to elucidate the role of Pgr in reproduction.

Results: We generated transgenic zebrafish Tg(pgr:eGFP) that express enhanced green fluorescent protein (eGFP) driven by promoter sequence of pgr gene.

Upregulation of adamts9 by gonadotropin in preovulatory follicles of zebrafish.

Previously we had identified adamts9 as a downstream target of Pgr, which is essential for ovulation in zebrafish. The primary goal of this study is to determine whether human chorionic gonadotropin (hCG, LH analog) also regulate adamts9 expression prior to ovulation. The expression of adamts9 was induced by hCG in a dose and time dependent manner in zebrafish preovulatory follicles in vitro.

Paralogues From the Expanded Tlr11 Gene Family in Mudskipper () Are Under Positive Selection and Respond Differently to LPS/Poly(I:C) Challenge.

Toll-like receptors (TLRs) are major molecular pattern recognition receptors, which are essential for triggering a series of innate immune responses against invading pathogens by recognizing their evolutionary conserved molecular patterns. The mudskipper, is exceptional among fishes due to its amphibious lifestyle and adaptation to living on mudflats. The whole-genome sequencing of has revealed that this species possesses an expansion of Tlr11 family [12 Tlr11 family genes (one , 4 , and 7 )] that we focused on in the present study.

Androgen induces olfactory expression of prostaglandin E receptor Ep1 in the burrow-living fish Bostrychus sinensis.

It is well documented that androgens modify olfactory processing in vertebrates. In fish, several lines of evidence indicate that androgens increase olfactory sensitivity to prostaglandin pheromone, but the molecular mechanism is still unclear. Our previous studies showed that prostaglandin E (PGE) is a sex pheromone in the burrowing-living fish Chinese black sleeper (Bostrychus sinensis) and that the PGE receptor 1 (Ep1) in the olfactory rosette is a candidate receptor for sensing sex pheromone PGE.

Progestin and Nuclear Progestin Receptor Are Essential for Upregulation of Metalloproteinase in Zebrafish Preovulatory Follicles.

Ovulation requires proteinases to promote the rupture of ovarian follicles. However, the identity of these proteinases remains unclear. In our previous studies using RNA-seq analysis of differential expressed genes, we found significant down-regulation of five metalloproteinases: (a disintegrin and metalloproteinase domain 8b), (a disintegrin and metalloproteinase with thrombospondin motif 8a), (matrix metalloproteinase 2), and in the nuclear progestin receptor knockout ( ) zebrafish that have failed to ovulate.

Involvement of Membrane Progestin Receptor Beta (mPRβ/Paqr8) in Sex Pheromone Progestin-Induced Expression of Luteinizing Hormone in the Pituitary of Male Chinese Black Sleeper ().

Our previous studies showed that 17α, 20β-dihydroxy-4-pregnen-3-one (DHP) acted as a sex pheromone to induce reproductive success in Chinese black sleeper (), but its functional mechanism remains unclear. In the present study, we cloned the cDNAs of the gonadotropin subunits (αβ, and β), and found that, in exposure to 5 nM DHP, transcript levels of β significantly increased in the pituitary at 6 h post exposure; plasma 11-KT levels increased at 24 h post exposure in mature male fish. In contrast, DHP exposure failed to increase the transcript levels of β in the pituitary of immature male fish, suggesting that the responsiveness to DHP depends on reproductive status.

Silver nanoparticles induce oocyte maturation in zebrafish (Danio rerio).

Public concern regarding silver nanoparticles (AgNPs) in the environment has been increasing since they can cause adverse effects in some aquatic species. However, few data are actually available on the effects of AgNPs on the germ cells. In the present study, we used the zebrafish ovarian follicle as a model to assess the potentially adverse effects of AgNPs on oocyte maturation (germinal vesicle breakdown, GVBD) in vitro.

Cloning and expression of two hepcidin genes in the mudskipper (Boleophthalmus pectinirostris) provides insights into their roles in male reproductive immunity.

The mudskipper Boleophthalmus pectinirostris is a burrow-dwelling fish inhabiting intertidal mudflats. During the spawning season, in a spawning chamber located at the center of their burrow, a pair of male and female fish mate and fertilized eggs adheres onto the inner walls and ceiling with filamentous attachments. During 5 days of incubation, the fertilized eggs are kept clean and hatch with a very high hatching rate under the natural conditions filled with microorganisms.

Molecular characterization and expression analysis of AMPK α subunit isoform genes from Scophthalmus maximus responding to salinity stress.

AMP-activated protein kinase (AMPK) is a highly conserved and multi-functional protein kinase that plays important roles in both intracellular energy balance and cellular stress response. In the present study, molecular characterization, tissue distribution and gene expression levels of the AMPK α1 and α2 genes from turbot (Scophthalmus maximus) under salinity stress are described. The complete coding regions of the AMPK α1 and α2 genes were isolated from turbot through degenerate primers in combination with RACE using muscle cDNA.

Identification, expression and antibacterial activities of an antimicrobial peptide NK-lysin from a marine fish Larimichthys crocea.

As fundamental immunologic mechanism, the innate immunity system is more important than the specific immunity system in teleost fishes during pathogens infection. Antimicrobial peptides are integral parts of the innate immune system, and play significant roles against pathogens infection. NK-lysin, the compounds of the natural killer cells and cytotoxic T cells, are potent and effective antimicrobial peptides widely distributed in animals.

Cloning and olfactory expression of progestin receptors in the Chinese black sleeper Bostrichthys sinensis.

Our previous studies suggested that 17α,20β-dihydroxy-4-pregnen-3-one (DHP), an oocyte maturation inducing progestin, also acts as a sex pheromone in Chinese black sleeper Bostrichthys sinensis, a fish species that inhabits intertidal zones and mates and spawns inside a muddy burrow. The electro-olfactogram response to DHP increased during the breeding season. In the present study, we cloned the cDNAs of the nine progestin receptors (pgr, paqr5, 6, 7(a, b), 8, 9, pgrmc1, 2) from B.

Cloning and pattern of gsdf mRNA during gonadal development in the protogynous Epinephelus akaara.

Gonadal soma-derived factor (gsdf) is a teleost- and gonad-specific growth factor involved in early germ cell development. The red spotted grouper, Epinephelus akaara, as a protogynous hermaphrodite, provides a novel model for understanding the mechanisms of sex determination and differentiation in teleosts. In the present study, a 2307-bp long gsdf gene was cloned from E.

The complete mitochondrial genome of the Royal dottyback Pictichromis paccagnellae (Perciformes: Pseudochromidae).

In this study, the complete mitogenome sequence of the Royal dottyback, Pictichromis paccagnellae (Perciformes: Pseudochromidae), has been sequenced by the next-generation sequencing method. The assembled mitogenome was of 16 976 bp in length, consisting of 13 protein-coding genes, 22 transfer RNAs, and two ribosomal RNAs genes. The overall base composition was 27.

The complete mitochondrial genome of the palette surgeonfish, Paracanthurus hepatus (Perciformes: Acanthuridae).

In this study, the complete mitogenome sequence of the palette surgeonfish, Paracanthurus hepatus (Perciformes: Acanthuridae), has been sequenced by next-generation sequencing method. The assembled mitogenome was 16 498 bp in length, consisted of 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs genes. The overall base composition of palette surgeonfish was 28.

Cloning and expression pattern of gsdf during the first maleness reproductive phase in the protandrous Acanthopagrus latus.

Gonadal soma-derived factor (Gsdf) is a new member of the transforming growth factor beta superfamily. As a teleost- and gonad-specific growth factor, several studies indicate that Gsdf plays an important role in early germ cell development. In the present study, for the first time, a 1700-bp long gsdf gene was cloned from a protandrous species, Acanthopagrus latus.

Cloning and expression of prostaglandin E2 receptor subtype 1 (ep 1 ) in Bostrichthys sinensis.

Our previous studies suggested that prostaglandin E2 (PGE2) is a putative sex pheromone in Chinese black sleeper Bostrichthys sinensis, a fish species that inhabits intertidal zones and mates and spawns inside a muddy burrow. We found immunoreactivities of PGE2 receptor subtypes (Ep1-3) expressed in the olfactory sac, but only Ep1 presented higher density of immunoreactivity in mature fish than that in immature fish in both sexes. To gain a better understanding of the underlying molecular mechanism for the detection of PGE2 in the olfactory system, we cloned an ep 1 cDNA from the adult olfactory sac.

Cloning and expression of melatonin receptors in the mudskipper Boleophthalmus pectinirostris: their role in synchronizing its semilunar spawning rhythm.

The mudskipper Boleophthalmus pectinirostris, a burrow-dwelling fish inhabiting intertidal mudflats, spawns only once during the spawning season around either the first or last lunar quarters. To understand the molecular mechanisms regulating this semilunar spawning rhythm, we cloned all melatonin receptor subtypes (mtnr1a1.4, mtnr1a1.

Characterization of RAG1 and IgM (mu chain) marking development of the immune system in red-spotted grouper (Epinephelus akaara).

In vertebrates, lymphoid-specific recombinase protein encoded by recombination-activating genes (RAG1/2) plays a key role in V(D)J recombination of the T-cell receptor and B-cell receptor. In this study, both RAG1 and the immunoglobulin M (IgM) mu chain were cloned to characterize their potential role in the immune defense at developmental stages of red-spotted grouper, Epinephelus akaara. The open reading frame (ORF) of E.