Prothymosin alpha (PTA) was detected by immunocytological and biochemical methods in oocytes at different stages of oogenesis, and in early embryos of the amphibian Bufo arenarum. In all cases PTA was detected in the nucleus and was absent from the cytoplasm. This indicates that this protein could act at the level of regulating transcription. Western blots were carried out using polyclonal antibodies with extracts of embryos at different stages of development from early fertilisation up to neural tube. With this method PTA was detected in all the samples under study.

Echinoid embryos of indirect developers comprise three tiers at the 16-cell stage: eight mesomeres, four macromeres and four micromeres. Micromeres differentiate autonomously into skeletogenic mesenchyme cells and induce adjoining macromeres to form a vegetal plate, resulting in archenteron invagination (Ransick & Davidson, 1995). It has been shown that micromeres have the potential to induce archenteron differentiation of presumptive ectoderm (Hörstadius, 1939).

Direct development, in which the larval stages are more or less abbreviated, has evolved in several phylogenetic lineages of echinoids. In most of them, the fourth cleavage of the embryos produces 16 blastomeres of almost the same size (Raff, 1987). Because of their indistinguishability, the inductive potential of vegetal-most blastomeres of direct developers remained to be studied.

The 16-cell stage embryos of the direct-developing sand dollar, Peronella japonica, are an exception and produce three tiers, the same as indirect developers. The embryos develop into two-armed pluteus-like larvae and metamorphose within 3 days after fertilisation without feeding. The micromeres of the species had been shown to differentiate into the skeletogenic mesenchyme cells (Amemiya & Arakawa, 1996). In the present study, we investigated the potential of the micromeres to induce or promote archenteron invagination in Peronella japonica.

To investigate the roles of lncRNA deleted in lymphocytic leukaemia 1 (DLEU1) on migration and invasion of human trophoblast cells. Human chorionic trophoblast cell line HTR8/SVneo was cultured and transfected using lncRNA DLEU1 small interfering RNA. Real-time quantitative polymerase chain reaction was used to detect lncRNA DLEU1 expression. The activity of migration regulatory protein CDC42 was detected by western blot. The downstream miRNA targets of lncRNA and mRNAs targeted by corresponding miRNAs were respectively predicted using bioinformatics analyses. Compared with the control group, the expression of lncRNA DLEU1 in the small interfering RNA group was significantly decreased (P < 0.05). There was no significant change in cell proliferation capacity for transfected cells (lncRNA DLEU1 siRNA-1, P = 0.537; lncRNA DLEU1 siRNA-2, P = 0.384), but cell migration (lncRNA DLEU1 siRNA-1, P = 0.025; lncRNA DLEU1 siRNA-2, P = 0.019) and invasion (lncRNA DLEU1 siRNA-1, P = 0.0327; lncRNA DLEU1 siRNA-2, P = 0.021) was significantly reduced. CDC42 activity in the lncRNA DLEU1 knockdown group decreased and the phosphorylation of cofilin increased. Therefore, downregulation of lncRNA DLEU1 suppressed the migration and invasion of human trophoblast cells.

The follicle-stimulating hormone (FSH) and its receptor regulate the quantity and quality of spermatozoa production. Several studies have analyzed the effect of single nucleotide polymorphisms (SNPs) in exon 10 of the FSH receptor (FSHR) on basic semen parameters without yet reaching a firm consensus. The aim of this study was to evaluate the effect of p.Thr307Ala and p.Asn680Ser polymorphisms in exon 10 of the FSHR gene, in infertile men, on intracytoplasmic sperm injection (ICSI) outcomes. This study was conducted between March 2019 and February 2020 on infertile couples undergoing ICSI at Al Hadi Laboratory and Medical Center, Lebanon. Couples with severe infertility factors that may impair gametogenesis/embryogenesis (e.g. advanced maternal age, premature ovarian failure, underwent gonadotoxic treatments, etc.) were excluded from the study. Semen and blood samples were collected from infertile men on the day of oocyte collection. Infertile men (n = 173) were screened for FSHR variants using polymerase chain reaction-restriction fragment length polymorphism. Moreover, fertilization rates, embryo quality, and pregnancy outcomes were evaluated. Higher sperm concentrations were found in the p.Thr307Ala group than the p.Thr307Thr (P < 0.01) and p.Ala307Ala (P < 0.05) groups. Furthermore, fertilization rate was significantly lower in the p.Ala307Ala genotype than in the p.Thr307Thr genotype (P < 0.05). We showed that FSHR variants in infertile men undergoing ICSI could affect sperm concentration, motility, and fertilization rates. Therefore, it will be important to confirm these results in further studies using a larger sample size.

The global transition towards diets high in calories has contributed to 2.1 billion people becoming overweight, or obese, which damages male reproduction and harms offspring. Recently, more and more studies have shown that paternal exposure to stress closely affects the health of offspring in an intergenerational and transgenerational way. SET Domain Containing 2 (SETD2), a key epigenetic gene, is highly conserved among species, is a crucial methyltransferase for converting histone 3 lysine 36 dimethylation (H3K36me2) into histone 3 lysine 36 trimethylation (H3K36me3), and plays an important regulator in the response to stress. In this study, we compared patterns of SETD2 expression and the H3K36me3 pattern in pre-implantation embryos derived from normal or obese mice induced by high diet. The results showed that SETD2 mRNA was significantly higher in the high-fat diet (HFD) group than the control diet (CD) group at the 2-cell, 4-cell, 8-cell, and 16-cell stages, and at the morula and blastocyst stages. The relative levels of H3K36me3 in the HFD group at the 2-cell, 4-cell, 8-cell, 16-cell, morula stage, and blastocyst stage were significantly higher than in the CD group. These results indicated that dietary changes in parental generation (F0) male mice fed a HFD were traceable in SETD2/H3K36me3 in embryos, and that a paternal high-fat diet brings about adverse effects for offspring that might be related to SETD2/H3K36me3, which throws new light on the effect of paternal obesity on offspring from an epigenetic perspective.

The Mexican tetra Astyanax mexicanus presents two contrasting morphs, a widely distributed surface morph and a cave-adapted morph. These cave-adapted morphs have evolved independently from two different lineages (i.e. ‘old’ and ‘new’ lineages); therefore, this model system gives a unique opportunity to explore parallel adaptive evolution in biological traits. The present study corresponds to the first morphological description of the Astyanax mexicanus maturation process of the spermatozoa and oocytes, using thermal and hormonal stimuli to promote spermatogenesis and oogenesis, considering surface and cave morphs from both lineages. We corroborate the relevance of thermal and hormonal stimuli to promote gamete maturation. The hormone Ovaprim (GnRHa + Domperidone) is an effective promoter of ovarian development, maturation end in oocytes and spawning in Astyanax mexicanus. The sperm morphology of Astyanax mexicanus includes the sperm head, the midpiece, and tail or flagellum. We found differences in the spermatozoan total length between environments (F = 9.929, P = 0.05) and linages (F = 49.86, P = 0.005). The oocytes showed a spherical conformation with a mean diameter of 822.4 ± 194.1 μm for the surface populations, and 604.6 ± 38.3 µm for the cave populations. The oocyte chorion presents ridges and grooves that are arranged radially towards the micropyle. A plug in the micropyle zone was observed after fertilization, confirmed by the outer membrane of the chorion, which provides some weak adhesiveness to the substrate. We observed differences in chorion thickness between the contrasting environmental conditions. This is the first morphological characterization of the Sótanos Vázquez, Escondido and Tigre, which previous to this study were only known from speleological expeditions, with no previous biological information available.

Commercial application of embryo transfer in pig breeding is dependent on the storage of embryos. The aim of this study was to assess the embryo quality of in vitro-produced blastocysts after 3 h liquid storage at 37°C in CO2-free medium by evaluating morphology, in vitro developmental capacity and apoptosis. Blastocysts at days 5 and 6 post-fertilization were randomly allocated to the storage group (HEPES-buffered NCSU-23 medium including bovine serum albumin in a portable embryo transport incubator at 37°C) or a control group (porcine blastocyst medium in a conventional culture incubator). Thereafter, blastocysts were evaluated for morphology and stained to assess apoptosis straight after the 3 h storage period or after a further 24 h conventional incubation. There was no significant difference between the storage and control group after 3 h storage and the further 24 h conventional incubation for any of the parameters, nor for apoptosis straight after the 3 h storage. Embryos that reached the blastocyst stage at day 5 showed less apoptosis (6.6% vs 10.9%, P = 0.01) and a trend for a higher rate of developmental capacity (70.6% vs 51.5%, P = 0.089) than embryos reaching the blastocyst stage on day 6. In conclusion, in vitro-produced porcine blastocysts can be stored for 3 h at physiological temperature in transportable incubators using a CO2-independent medium without compromising quality.

The objective of the current study was to investigate the influence of synergism of the dry powder of Alpinia galanga rhizomes (AGR) and/or zinc sulfate in the diet on semen quality and reproductive traits of California rabbit bucks. The study was conducted in two stages. First stage: appreciation of semen characteristics, 36 California rabbit bucks (aged 5 months) with average body weights of 2980 g were divided randomly into six treatments (six individuals each). The treatment groups were: first group, control fed basal diet (C); second group, fed basal diet plus 1 g AGR/kg dry matter (DM) (AGR1); third group, fed basal diet plus 2 g AGR/kg DM (AGR2); fourth group, fed basal diet plus 200 mg Zn/litre drinking water (Zn); fifth group, fed basal diet plus 1 g AGR/kg DM and 200 mg Zn/litre drinking water (AGR1 + Zn); sixth group, fed basal diet plus 2 g AGR/kg DM and 200 mg Zn/litre drinking water (AGR2 + Zn). Second stage: the previous bucks were used to determine the efficiency of semen on reproductive fertility traits, 48 mature does (aged 6 months, nulliparous) with an average body weight of 3050 ± 20.7 g were divided randomly into six treatments and inseminated with previous groups of treated bucks. The results of the first stage, recorded high activity on gonadotropins hormones: follicle-stimulating hormone (FSH) and luteinizing hormone (LH), free testosterone (FT), progesterone (P4) and oestrogen (E217β) concentrations for AGR1 + Zn and AGR2 + Zn compared with the control group. Groups AGR1, AGR2, AGR1 + Zn and AGR2 + Zn had significantly lowered concentrations of triglycerides, total cholesterol, low-density lipoprotein, and malondialdehyde (MDA), whereas high-density lipoprotein and total antioxidant capacity (TAC) were increased significantly compared with the control group. The group supplemented with AGR with or without Zn had significantly improved ejaculate volume, advanced motility, sperm concentration, and cell integrity. Fertility rate and litter size were improved in all groups compared with the control. It was concluded that supplementing diets with Alpinia galanga and Zn significantly increased sperm percentage, motility and reproductive hormones (testosterone, FSH, LH, E217β, P4). This suggested that this plant when used may be favourable for improved sperm quality and fertility parameters.

We describe for the first time the cytogenetic characteristics of mouse ‘embryos’ obtained by oocyte fusion (oocyte fusion products; OFP). Our results indicate that, after fusion, meiosis II is resumed correctly, with extrusion of two haploid polar bodies, and that metaphase synchronisation of the two haploid sets and chromosome segregation during the first cleavage are also normal.

Pretreatment of zona-free Chinese hamster (CH) oocytes with three kinds of lectin – concanavalin A (Con-A), phytohaemagglutinin-P (PHA) and wheat germ agglutinin (WGA) – was attempted in order to improve penetration by golden hamster (GH) spermatozoa in vitro. Con-A had no significant effect on penetration at 2 μg/ml, adequately facilitated oocyte-sperm fusion at 4 μg/ml, and caused excessive sperm binding and resultant severe polyspermy at 10 μg/ml. Neither PHA nor WGA had positive effects on sperm penetration at any concentrations (2–10 μg/ml) examined. Using the Con-A (4 μg/ml)pretreatment, high rates of interspecific fertilisation and subsequent chromosome analysis of hybrid 1-cell zygotes were achieved. Among 258 CH oocytes used, 212 (82.2%) were fertilised and 153 (72.2% of fertilised ova) developed to the first cleavage metaphase. Eventually, 132 CH-derived chromosome complements and 153 GH-derived ones were successfully karyoanalysed. Incidences of aneuploidy and structural anomaly were 3.1% and 2.3% in CH complements, and 1.4% and 6.5% in GH complements, respectively. These incidences were not significantly different from those obtained by intraspecific in vivo fertilisation, suggesting that our interspecific in vitro fertilisation system does not cause chromosome aberrations.

Zygotic genome activation (ZGA) is a critical event in early embryonic development, and thousands of genes are involved in this delicate and sophisticated biological process. To date, however, only a handful of these genes have revealed their core functions in this special process, and therefore the roles of other genes still remain unclear. In the present study, we used previously published transcriptome profiling to identify potential key genes (candidate genes) in minor ZGA and major ZGA in both human and mouse specimens, and further identified the conserved genes across species. Our results showed that 887 and 760 genes, respectively, were thought to be specific to human and mouse in major ZGA, and the other 135 genes were considered to be orthologous genes. Moreover, the conserved genes were most enriched in rRNA processing in the nucleus and cytosol, ribonucleoprotein complex biogenesis, ribonucleoprotein complex assembly and ribosome large subunit biogenesis. The findings of this first comprehensive identification and characterization of candidate genes in minor and major ZGA provide relevant insights for future studies on ZGA.