Amh Gene Research Articles

Anti-Müllerian hormone deficiency leads to two distinct ovarian phenotypes with different alterations of sex hormones in gynogenetic carp

Anti-Müllerian hormone (Amh) plays conserved roles in gonadal development and function in vertebrates. Previous studies have demonstrated that amh deficiency results in severe gonadal hypertrophy in teleost. Here, we report a novel phenotype of gonadal atrophy caused by amh knockout in fish. Firstly, it was found that the amh gene had three alleles and was expressed in the cytoplasm of follicle cells in gynogenetic amphiploid gibel carp (Carassius gibelio). Subsequently, we constructed a mutant line of amh and identified two distinct ovarian abnormalities in gibel carp. Most mutants exhibited hypertrophic ovaries with increased proliferation and decreased differentiation of early germ cells, which is consistent with previously reported findings. Intriguingly, a small number of mutants displayed atrophic ovaries with decreased proliferation and premature differentiation of germ cells, which represents a novel phenotype in fish species. Transcriptome analysis revealed that these two distinct ovaries of amh mutants showed different alterations in the sex hormone biosynthesis pathway, when compared with wild-type ovaries. Furthermore, diverse gonadal sex hormone levels were also detected in these two abnormal ovaries, which were consistent with the transcriptional expressions of corresponding genes in the sex hormone synthesis pathway. These findings identify a novel atrophic ovarian phenotype of amh mutants and confirm the amh function in controlling the balance between proliferation and differentiation of germ cells in fish.

Comparable to 17α- methyl testosterone, dietary supplements of Tribulus terrestris and Mucuna pruriens promote the development of mono-sex, all-male tilapia fry, growth, survival rate and sex-related genes (Amh, Sox9, Foxl2, Dmrt1)

To evaluate Tribulus terrestris and Mucuna pruriens for inducing all-male tilapia, mixed-sex Nile tilapia, Oreochromis niloticus, (mean weight 0.025 ± 0.009 g; mean length 1.25 ± 0.012 cm), were given a meal supplemented with either T. terrestris powder (commercial fish feed, 40% crude protein) (TT group), M. pruriens seed extract (MP group), MP + TT (mixed group), 17α-methyl testosterone (MT, control positive), or without supplements (control negative). The MP extracts significantly increased (P < 0.05) the final weight, weight gain, weight gain rate, and specific growth rate while feed conversion ratio was significantly decreased (P < 0.05). Plant extracts markedly improved (P < 0.05) the survival rate, proportion of males, and total testosterone compared to control and MT. Estrogen levels were lower in groups with plant extract than other groups. Fifteen days post-feeding, the Amh gene was expressed in the brain of O. niloticus fries with higher levels in MP, TT, and MT groups. Additionally, the expression of the Sox9 and Dmrt1 genes as a male related genes in fish fry gonads revealed significantly (P < 0.05) higher levels in groups fed on MP, TT, and MT compared to control after 30-day post-feeding, whereas; Foxl2 gene expression as a female related gene was significantly (P < 0.05) lower in fish fed on MP, TT, and MT compared to other groups after 30 days post feeding. Histologically, MT, MP, TT, and the mixture all exhibited solely male reproductive traits without noticeable abnormalities. This study concluded that each of the TT or MP extracts can induce sex reversal in tilapia while having no negative health impact compared to MT as the growth and survival rate in the treated groups with TT and MP were higher than control and group treated with MT.

Un association of Anti-Mullerian Hormone gene (rs4807216) polymorphism in Polycystic Ovary Syndrome (PCOS) Among Iraqi Women

The current work aimed to assess the hormonal profile of women with PCOS, including the AMH hormone and the AMH gene (rs4807216) polymorphism. The blood samples were obtained from 60 patients with PCOs who visited Reproductive Medicine Centre of General Hospital of Kirkuk and 30 healthy women. The serum level of LH, FSH, TSH, Estrogen and AMH determined by Enzyme linked immunosorbent assay (ELISA), while Polymerase chain reaction (PCR) was used to genotype the AMH gene (rs4807216). The current results showed a significant increase in LH, TSH, Estrogen, and AMH serum levels in PCOS females as compared to the control female group at P value= 0.05. In contrast, the serum level of FSH was not significantly increased at p value = 0.05. Polymorphism rs4807216was not significantly associated with serum AMH levels in the population study. In conclusion, Women with PCOS have high levels of LH, TSH, Estrogen, and AMH. Therefore, these hormones consider biomarkers for detecting PCOS in Iraqi females.

Investigating the interplay between AMH gene polymorphism rs10407022 and clinical indicators in polycystic ovary syndrome

PurposePCOS is a multifaceted endocrine disorder with a complex etiology that includes genetic and environmental influences. The Anti-Mullerian Hormone is essential in menstrual disorders and fertility, as it is involved in growth differentiation and folliculogenesis. The AMH gene polymorphism, specifically p.Ile49Ser, has been proposed to play a role in the pathogenesis of PCOS, but its significance in Indian populations has yet to be determined. MethodsA case-control study was carried out on 129 women from Gujarat, India, aged 13 to 40 years (59 with PCOS and 70 controls). Clinical, biochemical, and hormonal parameters were examined, and tetra-ARMS PCR was used for genotyping the AMH gene polymorphism (p.Ile49Ser). The relationships between polymorphism, hormonal imbalances, and PCOS were studied using different statistical methods. ResultsThe mean BMI in the PCOS group was significantly higher (27.32 ± 5.71) in comparison to the control group (23.81 ± 5.47, p = 0.001), with 67.80% of PCOS cases being obese. Notably, serum LH and T levels were significantly higher in PCOS women, whereas DHEAS levels were significantly lower (p < 0.05). However, the distribution of AMH gene rs10407022 genotypes and alleles did not differ significantly between groups, and no associations with PCOS risk were found. ConclusionObesity and hormonal imbalances have a significant impact on PCOS in Gujarati women, according to this study. Even though the AMH gene polymorphism (p.Ile49Ser) did not show a significant association with PCOS, the findings encourage further genetic research in diverse Indian populations to uncover the complex genetic background of PCOS.

Identifying infrequent genetic changes in monozygotic twins afflicted with hypospadias via targeted panel sequencing.

We aimed to identify the genetic causes of hypospadias in children using targeted gene panel sequencing for disorders of sex development (DSD). This study included 18 twin boys with hypospadias: seven and two pairs were monozygotic and dizygotic twins, respectively, and six were discordant and three were concordant twins. Targeted gene panel sequencing for 67 known DSD genes was performed. Sequence variants were classified into five different categories, pathogenic, likely pathogenic, variants of uncertain significance, likely benign, and benign, following the American College of Medical Genetics and Genomics Standards and Guidelines. The mean gestational age and birth weight were 35.3±2.0 weeks and 1.96±0.61 kg, respectively, with seven patients being small for gestational age. Hypospadias was present in 12 patients, with posterior type in 33.3% and anterior type in 66.7%. In three families with twins, both siblings had hypospadias. In addition, cryptorchidism was observed in one subject. Surgical correction of hypospadias was performed at a mean age of 22.1 months. Molecular analysis identified 12 different genetic variants, including two pathogenic mutations in the AMH (p.E389*) and SRD5A2 (p.R246Q) genes, found in subjects with hypospadias, respectively. However, only heterozygous mutations were detected. This study did not identify a definitive genetic component contributing to the development of hypospadias; however, the findings suggest that intrauterine growth retardation may play a significant role.

Whole-genome sequencing identified candidate genes associated with high and low litter size in Chuanzhong black goats.

The reproductive performance of goats significantly influences breeding efficiency and economic returns, with litter size serving as a comprehensive indicator. Despite this, research on the genetic control of litter size remains limited. Therefore, we aimed to explore the candidate genes affecting fecundity and compared the whole-genome sequences (WGS) of 15 high-litter (HL) and 15 low-litter (LL) size in Chuanzhong black goats. Then genetic diversity and genomic variation patterns were analyzed by phylogenetic, principal component and population genetic structure analysis, it was found that HL and LL subpopulations diverged. Population evolutionary selection elimination analysis was performed by Fst and θπ resulted in 506 genes were annotated in HL and 528 genes in LL. These genes were mainly related to Hippo signaling pathway, G protein-coupled signaling pathway, G protein-coupled receptor activity, cell surface receptor signaling pathway, gonadal and reproductive structure development. According to the significantly selected genomic regions and important pathways, we found that the g.89172108T > G variant locus in the exon of the AMH gene was significantly associated with litter size (P < 0.05), which could be used as an auxiliary selection gene for the high fertility of Chuanzhong black Goat.

Role of parthenolide in paclitaxel-induced oxidative stress injury and impaired reproductive function in rat testicular tissue

The chemotherapeutic agent paclitaxel (PTX) causes testicular toxicity due to oxidative stress. Parthenolide (PTL), the active ingredient of the Tanacetum parthenium plant, is used to treat inflammation, dizziness, and spasms. In the present study, we evaluated the therapeutic effect of PTL on PTX-induced testicular toxicity in rats and its role in reproductive function. To this end, 6 groups were formed: control, PTX, sham, T1, T2, and T3. After testicular toxicity was induced in rats with 8 mg/kg PTX, the rats were treated with 1 mg/kg, 2 mg/kg, and 4 mg/kg PTL for 14 days. GSH and MDA levels were measured in rat testicular tissue after the last dose of PTL was administered. To determine the damage caused by PTX to testicular tissue by detecting 8-OHdG and iNOS, sections were prepared and examined histopathologically and immunohistochemically. Furthermore, the gene expressions and enzymatic activities of SOD, CAT, GPx, GST, and GR were investigated in all groups. After PTL treatment, MDA, 8-OHdG, and iNOS levels decreased while GSH levels increased in testicular tissue. Increased levels of antioxidant genes and enzymes also reduced oxidative stress. Additionally, the expression levels of the Dazl, Ddx4, and Amh genes, which are involved in gametogenesis and sperm production, decreased in case of toxicity and increased with PTL treatment. The data from this study show that PTL may have a therapeutic effect in the treatment of testicular damage by eliminating the oxidative stress-induced damage caused by PTX in testicular tissue, providing an effective approach to alleviating testicular toxicity, and playing an important role in reproduction/sperm production, especially at a dose of 4 mg/kg.

In Silico Chromosome Mapping of the Male-Specific/Linked Loci in the Jade Perch (Scortum barcoo) Suggests Chromosome 19 as the Putative Y Sex Chromosome

Jade perch (Scortum barcoo) has an XX/XY sex-determination system (SDS); however, its sex chromosomes and sex-determining region remain unknown. The recent availability of the jade perch chromosome-level genomic data provides a valuable resource for pinpointing the location of functional genes and the whole genomic structure. In this study, we conducted. In silico chromosome mapping of male-specific/linked loci of jade perch and identified a potential 11.18 Mb male-linked region localized on chromosome 19 (SBA19). Repeat annotations of the male-linked region revealed an abundance of transposable elements, particularly Ty3/Gypsy and novel repeats. Sequence analysis of this region identified a remnant of amh gene, which is considered a potential candidate for SDS in many teleosts. A duplicate copy of amh remnant was located at SBA6. These duplicated amh copies were highly similar to those of XX/XY SDS in teleosts, in which one copy of amh was identified on the Y sex chromosome. Taken all together, we hypothesize SBA19 as the putative sex chromosome and the 11.18 Mb male-linked region to be a potential male-determining region.

Sex-Associated SNP Confirmation of Sex-Reversed Male Farmed Japanese Flounder Paralichthys olivaceus.

Female Japanese flounder Paralichthys olivaceus grow more rapidly than the male. The goal of all-female commercial production requires an efficient method of genetic sex identification. We conducted genome-wide association analysis of female and male farmed Japanese flounder (n = 24 per phenotypic sex) and found all regions of chromosome 24 to be significantly associated with phenotypic sex, suggesting it as the sex chromosome. Genetic sex was identified based on single nucleotide polymorphisms (SNP) on chromosome 24 (n = 3568) using multidimensional scaling analysis, and individuals were clearly separated according to sex by the first dimension. The 61 SNPs most highly associated with sex were selected, and an amplicon-based SNP panel was developed. This was used to determine genetic sex of 39 females and 40 males. Eleven phenotypic males were assigned as female with XX genotype, suggesting sex reversal. Genetic sex was also assessed based on the indel of the amh gene promoter, which is the major candidate sex gene of Japanese flounder. We found four SNPs perfectly associated with genotypic sex in the sex-associated SNP panel, one of which was located in exon 2 of the amh gene. Along with the indel of the amh gene promoter, the sex-associated SNP panel will be of value in identifying genetic sex of farmed Japanese flounder. Molecular sexing will facilitate all-female production by breeding sex-reversed males.

Sequencing analysis of anti mullerian hormone in polycystic ovarian syndrome and primary ovarian insufficiency

Link of Video Abstract: https://youtu.be/HvI9j8B9vqE Introduction: Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women of reproductive age and is the main cause of ovulation disorders. Primary ovarian insufficiency (POI) is a clinical syndrome characterized by loss of ovarian activity before the age of 40 years. All of these disorders lead to the risk of infertility. Therefore, this study aims to assess the AMH gene sequence and the effect of SNP on AMH levels and function. Method: This research was a cross-sectional study. The sample was divided into three groups such as PCOS, POI, and control. This study used ELISA and PCR examination methods. Research data were analyzed using IBM SPSS version 22. The statistical analyses used were the ANOVA, Kruskal-Wallis, chi-square, and Spearman tests. A significant p-value was ≤ 0.05. Results: There were 31 research subjects, 8 POI subjects, 16 PCOS subjects, and 7 control subjects. Overall 30 mutations were found, with two mutations in the gene promoter and 28 mutations in the structure of the AMH gene. Five mutations in the AMH gene structure were missense mutations. 14 SNPs were found in the POI group and 15 SNPs in the PCOS group. There was a significant difference in AMH AMH gene promoter mutation frequency distribution between the POI and PCOS groups at the mutation point 19:g.2249146T&gt;G (p=0.007). In contrast, the mutation point 19:g.2249158T&gt;A was not significantly different (p=0.536). There was no significant correlation between the number of promoter mutations and AMH gene structure with AMH levels in the POI, PCOS and control groups. Conclusion: There were mutations in the promoter and AMH gene structure of the POI, PCOS, and control groups which caused differences in base sequences. However, in this study, the differences in mutations were not significantly different.

Oocyte secreted factors control genes regulating FSH signaling and the maturation cascade in cumulus cells: the oocyte is not in a hurry.

To assess the effects of the oocyte on mRNA abundance of FSHR, AMH and major genes of the maturation cascade (AREG, EREG, ADAM17, EGFR, PTGS2, TNFAIP6, PTX3, and HAS2) in bovine cumulus cells. (1) Intact cumulus-oocyte complexes, (2) microsurgically oocytectomized cumulus-oolema complexes (OOX), and (3) OOX + denuded oocytes (OOX+DO) were subjected to in vitro maturation (IVM) stimulated with FSH for 22 h or with AREG for 4 and 22 h. After IVM, cumulus cells were separated and relative mRNA abundance was measured by RT-qPCR. After 22 h of FSH-stimulated IVM, oocytectomy increased FSHR mRNA levels (p=0.005) while decreasing those of AMH (p=0.0004). In parallel, oocytectomy increased mRNA abundance of AREG, EREG, ADAM17, PTGS2, TNFAIP6, and PTX3, while decreasing that of HAS2 (p<0.02). All these effects were abrogated in OOX+DO. Oocytectomy also reduced EGFR mRNA levels (p=0.009), which was not reverted in OOX+DO. The stimulatory effect of oocytectomy on AREG mRNA abundance (p=0.01) and its neutralization in OOX+DO was again observed after 4 h of AREG-stimulated IVM. After 22 h of AREG-stimulated IVM, oocytectomy and addition of DOs to OOX caused the same effects on gene expression observed after 22 h of FSH-stimulated IVM, except for ADAM17 (p<0.025). These findings suggest that oocyte-secreted factors inhibit FSH signaling and the expression of major genes of the maturation cascade in cumulus cells. These may be important actions of the oocyte favoring its communication with cumulus cells and preventing premature activation of the maturation cascade.

Analysis of the effect of triclosan on gonadal differentiation of zebrafish based on metabolome

Although the previous research confirmed that triclosan (TCS) affects the female proportion at the early stage of zebrafish (Danio rerio) and has an estrogen effect, the mechanism by which TCS affects the sex differentiation of zebrafish is not entirely clear. In this study, zebrafish embryos were exposed to different concentrations of TCS (0, 2, 10, and 50 μg/L) for 50 consecutive days. The expression of sex differentiation related genes and metabolites were then determined in larvae using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Liquid Chromatography-Mass Spectrometer (LC-MS), respectively. TCS upregulated the expression of the sox9a, dmrt1a and amh genes, down-regulating the expression of wnt4a, cyp19a1b, cyp19a1a, and vtg2 gene. The overlapped classification of Significant Differential Metabolites (SDMs) between the control group and three TCS treated groups related to gonadal differentiation was Steroids and steroid derivatives, including 24 down-regulated SDMs. The enriched pathways related to gonadal differentiation were Steroid hormone biosynthesis, Retinol metabolism, Metabolism of xenobiotics by cytochrome P450, and Cortisol synthesis and secretion. Moreover, SDMs were significantly enriched in Steroid hormone biosynthesis in the 2 μg/L TCS group, which included Dihydrotestosterone, Cortisol, 11beta-hydroxyandrost-4-ene-3, 17-dione, 21-Hydroxypregnenolone, Androsterone, Androsterone glucuronide, Estriol, Estradiol, 19-Hydroxytestosterone, Cholesterol, Testosterone, and Cortisone acetate. Results showed that TCS affects the female proportion mainly through Steroid hormone biosynthesis, in which aromatase plays a key role in zebrafish. Retinol metabolism, metabolism of xenobiotics by cytochrome P450, and cortisol synthesis and secretion may also participate in TCS-mediated sex differentiation. These findings reveal the molecular mechanisms of TCS-induced sex differentiation, and provide theoretical guidance for the maintenance of water ecological balance.

Protein-protein networks analysis of differentially expressed genes unveils the key phenomenon of biological process with respect to reproduction in endangered catfish, C. Magur

Clarias magur (magur) is an important freshwater catfish with high potential in the aquaculture sector in its geographical ranges of distribution. One of the impediments to realise its full aquaculture potential is the lack of understanding key genes involved in its reproduction pathways. Nonetheless, very limited information is available on brain and gonads, with respect to reproduction related issues of magur at molecular level. The present study was aimed at understanding the interaction of the brain-gonad system by analysing differentially expressed genes (DEG) in brains and gonads of male and female magur using a protein–protein network interaction study. In brief, 641, 541, 225 and 245 DEGs, respectively, in ovary, testis and female brain and male-brain of magur were used as input in String database 11.0 and Cytoscape v 3.8.0 plug-in Network Analyzer for PPI network construction followed by network superimposition, network merging and analysis. A total of 13 key genes in female brain & ovary and 12 key genes in male brain & testis were obtained based on the network topological parameter betweenness centrality and nodes degree. Among them, cyp19a1b and amh genes in male brain-testis and Tp53 and exo1 genes in female brain-ovary were identified as hub genes having a high level of interaction and expression with other key genes in the network. Further, functional annotation study of these genes revealed their active involvement in important pathways related to reproduction. This is the first report exploring the interaction of brain and gonads in the regulation of magur reproduction through a protein–protein interaction network. The 25 key genes identified in the combined network are involved in various pathways, like neuropeptide signalling pathway, oxytocin receptor-mediated signalling pathway, corticotrophin-releasing factor receptor signalling pathway and reproduction process, which could lead to a better understanding of the magur reproductive system.

Madagascar Leaf-Tail Geckos (Uroplatus spp.) Share Independently Evolved Differentiated ZZ/ZW Sex Chromosomes.

Geckos are an excellent group to study the evolution of sex determination, as they possess a remarkable variability ranging from a complete absence of sex chromosomes to highly differentiated sex chromosomes. We explored sex determination in the Madagascar leaf-tail geckos of the genus Uroplatus. The cytogenetic analyses revealed highly heterochromatic W chromosomes in all three examined species (Uroplatus&nbsp;henkeli, U.&nbsp;alluaudi, U. sikorae). The comparative gene coverage analysis between sexes in U.&nbsp;henkeli uncovered an extensive Z-specific region, with a gene content shared with the chicken chromosomes 8, 20, 26 and 28. The genomic region homologous to chicken chromosome 28 has been independently co-opted for the role of sex chromosomes in several vertebrate lineages, including monitors, beaded lizards and monotremes, perhaps because it contains the amh gene, whose homologs were repeatedly recruited as a sex-determining locus. We demonstrate that all tested species of leaf-tail geckos share homologous sex chromosomes despite the differences in shape and size of their W chromosomes, which are not homologous to the sex chromosomes of other closely related genera. The rather old (at least 40 million years), highly differentiated sex chromosomes of Uroplatus geckos can serve as a great system to study the convergence of sex chromosomes evolved from the same genomic region.

Y-specific amh allele, amhy, is the master sex-determining gene in Japanese flounder Paralichthys olivaceus.

Japanese flounder (Paralichthys olivaceus) is an important marine fish species of both fisheries and aquaculture in Northeast Asia. The commercial interest for all-female progenies due to several sex-related traits has prompted basic research on the mechanisms of sex determination in this species. By conducting a linkage analysis of the sex-determining locus, we initially identified 12 microsatellite markers linked to sex in 11 scaffolds, whose localization was restricted to a specific region of linkage group 9. Sequence analysis of this region identified 181 genes based on the UniProt database annotations. Among them, the amh gene was considered a potential candidate for sex determination because this gene is known to have taken over the role of sex determination in many teleosts. An in-depth sequence analysis of both the coding and non-coding regions of amh in XX and XY individuals detected nine SNPs linked with maleness. However, because these substitutions were synonymous, the upstream and downstream regions of amh were also investigated and a male-specific variant with deletions in the promoter region was detected. This truncated Y-specific amh variant was named amhy, and the amh shared by both sexes was named amhx. The association analysis using both females and males of the genotypic sex inferred by the presence/absence of amhy found complete association with phenotypic sex and genotype. Gene expression analysis in larvae derived from a single-pair progeny by quantitative real-time PCR detected amhy transcripts in the larval trunks between 20 and 100 days after hatching only in XY larvae. Localization of amhy by in situ hybridization was detected in presumptive Sertoli cells of XY gonads. Expression of amhx was almost undetectable in both XX and XY genotypes. Loss of Amh function by CRISPR-Cas9 induced male-to-female sex reversal, indicating that this gene was necessary for the masculinization of XY individuals. In conclusion, the complete linkage of amhy with males, its early expression in XY gonads before testicular differentiation, and the induction of sex reversal by loss-of-function mutation support the view that amhy is the sex-determining gene in this species.

Knock-down of amh transcription by antisense RNA reduces FSH and increases follicular atresia in female Oreochromis niloticus

Anti-Müllerian hormone (Amh) plays an important role in regulating gonad development in teleosts. However, little is known about the effects of Amh on follicle development. In this study, we transfected the vector containing antisense RNA fragments of the amh gene to produce Nile tilapia, Oreochromis niloticus, with knocked-down Amh function in vivo. The results confirmed that the antisense RNA effectively inhibited amh transcription and Amh protein expression in female tilapia ovarian tissue. At 180 days of age, compared with control fish, female tilapia with knocked-down Amh function showed significantly increased growth and significantly decreased ovary weight and gonadosomatic index (P < 0.05). Female fish in the control group had ruddy-colored external genitalia, eggs extruded from the abdomen when gently squeezed, and most oocytes were developmental stage V. In contrast, the external genitalia of female fish with knocked-down Amh function did not have the ruddy color, no eggs extruded from the abdomen when squeezed, most oocytes were at developmental stages II and III, and considerable follicular atresia was apparent. At 180 days of age, the transcript levels of amhrII, cyp19a1a, foxl2 and sox9b in ovarian tissue, and the titers of luteinizing hormone, follicle stimulating hormone, and estradiol in the serum, were significantly lower in fish with knocked-down Amh function than in control fish (P < 0.05). We concluded that decreased serum hormone levels and an abnormal AMH signal delayed development and caused follicular degeneration in Nile tilapia with knocked-down Amh function. These findings show that antisense RNA is a feasible approach for gene silencing in fish, and represents an accurate and effective strategy to study gene function.

The miR-200 Family Targeting amh Affects the Gonadal Development of Japanese Flounder

Four members of the miR-200 family in Japanese flounder (Paralichthys olivaceus) have sex-biased expression patterns, but their target genes and how they work in the development of the gonads are rarely known. Anti-Müllerian hormone (AMH) can inhibit the development of Muller’s duct in female mammals and regulate the formation of gametes after sexual maturity. There is no Muller’s duct in teleosts, but the amh gene still exists. Knockout of amh results in sex reversal from male to female. Therefore, it is essential to explore the relationship between the miR-200 family and amh to clarify what role miR-200 plays in the development of the gonads. In Japanese flounder, the two binding sites for the miR-200 family in the 3′UTR of amh were found through bioinformatic prediction. Double luciferase and green fluorescent protein reporter experiments demonstrated amh to be directly targeted by miR-200a and miR-200b. Moreover, miR-200a and miR-200b reduced the expression of amh through site 1 rather than site 2. To explore the regulatory role of miR-200a in gonadal development, we further overexpressed miR-200a in the primary Sertoli cells of the testis. With the overexpression of miR-200a, the expression of amh decreased, while the expression of the other two male sex-related genes, dmrt1 (doublesex and mab-3 related transcription factor 1) and gsdf (diagonal soma driven factor), increased significantly. This result indicates that the miR-200 family regulates the gonadal differentiation and development by targeting amh in Japanese flounder.

Polymorphism of Sex Determination Amongst Wild Populations Suggests its Rapid Turnover Within the Nile Tilapia Species.

Sex-determining regions have been identified in the Nile tilapia on linkage groups (LG) 1, 20 and 23, depending on the domesticated strains used. Sex determining studies on wild populations of this species are scarce. Previous work on two wild populations, from Lake Volta (Ghana) and from Lake Koka (Ethiopia), found the sex-determining region on LG23. These populations have a Y-specific tandem duplication containing two copies of the Anti-Müllerian Hormone amh gene (named amhY and amhΔY). Here, we performed a whole-genome short-reads analysis using male and female pools on a third wild population from Lake Hora (Ethiopia). We found no association of sex with LG23, and no duplication of the amh gene. Furthermore, we found no evidence of sex linkage on LG1 or on any other LGs. Long read whole genome sequencing of a male from each population confirmed the absence of a duplicated region on LG23 in the Lake Hora male. In contrast, long reads established the structure of the Y haplotype in Koka and Kpandu males and the order of the genes in the duplicated region. Phylogenies constructed on the nuclear and mitochondrial genomes, showed a closer relationship between the two Ethiopian populations compared to the Ghanaian population, implying an absence of the LG23Y sex-determination region in Lake Hora males. Our study supports the hypothesis that the amh region is not the sex-determining region in Hora males. The absence of the Y amh duplication in the Lake Hora population reflects a rapid change in sex determination within Nile tilapia populations. The genetic basis of sex determination in the Lake Hora population remains unknown.

Dietary Fibre Supplementation Improves Semen Production by Increasing Leydig Cells and Testosterone Synthesis in a Growing Boar Model.

Testicular development is imperative to spermatogenesis, and pre-puberty is the key period for testis development. This study, therefore, investigated the effects of fibre supplementation on testis development and its possible mechanism in a growing boar model. Thirty Yorkshire boars were randomly divided into a control group (Control) and a fibre group (Fibre) from day 0 to 90 after weaning, with three pigs per pen and five pens per treatment. Blood and testes were collected for analysis. Dietary fibre supplementation had no significant effect on growth performance, testicular volume, or libido but increased the semen production of boars. Boars fed with fibre had lower serum cholesterol (CHO) and low-density lipoprotein (LDL) levels compared to those on the Control diet; however, testicular CHO, triglyceride (TG), and LDL concentration in the Fibre group were significantly higher than the Control group (P < 0.01). Testicular histological analysis showed that seminiferous tubules and testicular germ cells of 120-day-old boars were densely arranged in the Fibre group, and the number of Leydig cells was significantly higher than that of the Control group (P < 0.001). Furthermore, the diet supplemented with fibre significantly decreased leptin, leptin receptor (Leptor), and luteinising hormone (LH) concentrations in boar serum (P < 0.05), whereas follicle-stimulating hormone (FSH) and testosterone concentrations were significantly increased (P < 0.05). Meanwhile, the expression of AMH, AMHR2, and SYCP3 genes related to proliferation and differentiation, and hormone-related genes STAR and SOCS3, were significantly up-regulated (P < 0.05). OCCLUDIN expression was up-regulated, whereas CDH2 expression was down-regulated. In conclusion, increased fibre intake during the pre-puberty period in growing boar is crucial for Leydig cell proliferation, up-regulating the expression of genes related to hormone synthesis and thereby promoting the secretion of testosterone and semen production.

Association of DNA Methylation in Blood Pressure-Related Genes With Ischemic Stroke Risk and Prognosis.

BackgroundA genome-wide association study identified 12 genetic loci influencing blood pressure and implicated a role of DNA methylation. However, the relationship between methylation and ischemic stroke has not yet been clarified. We conducted a large-sample sequencing study to identify blood leukocyte DNA methylations as novel biomarkers for ischemic stroke risk and prognosis based on previously identified genetic loci.MethodsMethylation levels of 17 genes were measured by sequencing in 271 ischemic stroke cases and 323 controls, and the significant associations were validated in another independent sample of 852 cases and 925 controls. The associations between methylation levels and ischemic stroke risk and prognosis were evaluated.ResultsMethylation of AMH, C17orf82, HDAC9, IGFBP3, LRRC10B, PDE3A, PRDM6, SYT7 and TBX2 was significantly associated with ischemic stroke. Compared to participants without any hypomethylated targets, the odds ratio (OR) (95% confidence interval, CI) for those with 9 hypomethylated genes was 1.41 (1.33–1.51) for ischemic stroke. Adding methylation levels of the 9 genes to the basic model of traditional risk factors significantly improved the risk stratification for ischemic stroke. Associations between AMH, HDAC9, IGFBP3, PDE3A and PRDM6 gene methylation and modified Rankin Scale scores were significant after adjustment for covariates. Lower methylation levels of AMH, C17orf82, PRDM6 and TBX2 were significantly associated with increased 3-month mortality. Compared to patients without any hypomethylated targets, the OR (95% CI) for those with 4 hypomethylated targets was 1.12 (1.08–1.15) for 3-month mortality (P = 2.28 × 10−10).ConclusionThe present study identified blood leukocyte DNA methylations as potential factors affecting ischemic stroke risk and prognosis among Han Chinese individuals.