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Human Reproduction (Oxford, England) Jan 2024Spontaneous dizygotic (DZ) twins, i.e. twins conceived without the use of ARTs, run in families and their prevalence varies widely around the globe. In contrast,... (Meta-Analysis)
Meta-Analysis
Spontaneous dizygotic (DZ) twins, i.e. twins conceived without the use of ARTs, run in families and their prevalence varies widely around the globe. In contrast, monozygotic (MZ) twins occur at a constant rate across time and geographical regions and, with some rare exceptions, do not cluster in families. The leading hypothesis for MZ twins, which arise when a zygote splits during preimplantation stages of development, is random occurrence. We have found the first series of genes underlying the liability of being the mother of DZ twins and have shown that being an MZ twin is strongly associated with a stable DNA methylation signature in child and adult somatic tissues. Because identical twins keep this molecular signature across the lifespan, this discovery opens up completely new possibilities for the retrospective diagnosis of whether a person is an MZ twin whose co-twin may have vanished in the early stages of pregnancy. Here, we summarize the gene finding results for mothers of DZ twins based on genetic association studies followed by meta-analysis, and further present the striking epigenetic results for MZ twins.
Topics: Female; Humans; Pregnancy; Fertilization; Genetic Association Studies; Retrospective Studies; Twins, Dizygotic; Twins, Monozygotic; Infant, Newborn
PubMed: 38052159
DOI: 10.1093/humrep/dead131 -
Nature Communications Aug 2023Somatic cell nuclear transfer (SCNT) can be used to reprogram differentiated somatic cells to a totipotent state but has poor efficiency in supporting full-term...
Somatic cell nuclear transfer (SCNT) can be used to reprogram differentiated somatic cells to a totipotent state but has poor efficiency in supporting full-term development. H3K9me3 is considered to be an epigenetic barrier to zygotic genomic activation in 2-cell SCNT embryos. However, the mechanism underlying the failure of H3K9me3 reprogramming during SCNT embryo development remains elusive. Here, we perform genome-wide profiling of H3K9me3 in cumulus cell-derived SCNT embryos. We find redundant H3K9me3 marks are closely related to defective minor zygotic genome activation. Moreover, SCNT blastocysts show severely indistinct lineage-specific H3K9me3 deposition. We identify MAX and MCRS1 as potential H3K9me3-related transcription factors and are essential for early embryogenesis. Overexpression of Max and Mcrs1 significantly benefits SCNT embryo development. Notably, MCRS1 partially rescues lineage-specific H3K9me3 allocation, and further improves the efficiency of full-term development. Importantly, our data confirm the conservation of deficient H3K9me3 differentiation in Sertoli cell-derived SCNT embryos, which may be regulated by alternative mechanisms.
Topics: Histones; Zygote; Nuclear Transfer Techniques; Embryonic Development; Blastocyst; Embryo, Mammalian; Cellular Reprogramming
PubMed: 37558707
DOI: 10.1038/s41467-023-40496-3 -
Comparative Cytogenetics 2023It is demonstrated that the initial method of fertilization in animals (Metazoa), embryophyte plants (Embryophyta), most groups of multicellular oogamous algae, oogamous... (Review)
Review
It is demonstrated that the initial method of fertilization in animals (Metazoa), embryophyte plants (Embryophyta), most groups of multicellular oogamous algae, oogamous and pseudoogamous multicellular fungi was internal fertilization (in the broad meaning) in/on the body of a maternal organism. Accordingly, during the bisexual process, the initial method of formation of a daughter multicellular organism in animals was viviparity, and in embryophyte plants and most groups of oogamous multicellular algae - the germination of a zygote in/on the body of maternal organism. The reproductive criteria of multicellularity are proposed and discussed. In this regard, the multicellularity is considered to subdivide terminologically into three variants: 1) protonemal, the most simple, characteristic of multicellular prokaryotes, most groups of multicellular algae and gametophytes of some higher plants; 2) siphonoseptal, found among multicellular fungi, some groups of green and yellow-green algae; 3) embryogenic, most complicated, known in all animals (Metazoa), all sporophytes and some gametophytes of higher plants (Embryophyta), charophyte green algae Charophyceae s.s., oogamous species of green and brown algae, some genera of red algae. In addition to the well-known division of reproduction methods into sexual and asexual, it is proposed to divide the reproduction of multicellular organisms into monocytic (the emergence of a new organism from one cell sexually or asexually) and polycytic (fragmentation, longitudinal / transverse division or budding based on many cells of the body of the mother organism), since these two ways have different evolutionary and ontogenetic origins.
PubMed: 37953852
DOI: 10.3897/compcytogen.17.109671 -
Critical Reviews in Food Science and... 2024Reproductive issues are becoming an increasing global problem. There is increasing interest in the relationship between microbiota and reproductive health. Stable... (Review)
Review
Reproductive issues are becoming an increasing global problem. There is increasing interest in the relationship between microbiota and reproductive health. Stable microbiota communities exist in the gut, reproductive tract, uterus, testes, and semen. Various effects (e.g., epigenetic modifications, nervous system, metabolism) of dysbiosis in the microbiota can impair gamete quality; interfere with zygote formation, embryo implantation, and embryo development; and increase disease susceptibility, thus adversely impacting reproductive capacity and pregnancy. The maintenance of a healthy microbiota can protect the host from pathogens, increase reproductive potential, and reduce the rates of adverse pregnancy outcomes. In conclusion, this review discusses microbiota in the male and female reproductive systems of multiple animal species. It explores the effects and mechanisms of microbiota on reproduction, factors that influence microbiota composition, and applications of microbiota in reproductive disorder treatment and detection. The findings support novel approaches for managing reproductive diseases through microbiota improvement and monitoring. In addition, it will stimulate further systematic explorations of microbiota-mediated effects on reproduction.
Topics: Pregnancy; Animals; Male; Female; Reproductive Health; Uterus; Pregnancy Outcome; Microbiota
PubMed: 36066460
DOI: 10.1080/10408398.2022.2117784 -
The Journal of Cell Biology Nov 2023Asymmetric meiotic divisions in oocytes rely on spindle positioning in close vicinity to the cortex. In metaphase II mouse oocytes, eccentric spindle positioning...
Asymmetric meiotic divisions in oocytes rely on spindle positioning in close vicinity to the cortex. In metaphase II mouse oocytes, eccentric spindle positioning triggers cortical polarization, including the build-up of an actin cap surrounded by a ring of activated myosin II. While the role of the actin cap in promoting polar body formation is established, ring myosin II activation mechanisms and functions have remained elusive. Here, we show that ring myosin II activation requires myotonic dystrophy kinase-related Cdc42-binding kinase (MRCK), downstream of polarized Cdc42. MRCK inhibition resulted in spindle rotation defects during anaphase II, precluding polar body extrusion. Remarkably, disengagement of segregated chromatids from the anaphase spindle could rescue rotation. We further show that the MRCK/myosin II pathway is activated in the fertilization cone and is required for male pronucleus migration toward the center of the zygote. These findings provide novel insights into the mechanism of myosin II activation in oocytes and its role in orchestrating asymmetric division and pronucleus centration.
Topics: Animals; Male; Mice; Actin Cytoskeleton; Actins; Cytoskeletal Proteins; Myosin Type II; Oocytes; Rotation; Female; Protein Serine-Threonine Kinases; Spindle Poles; Anaphase
PubMed: 37651121
DOI: 10.1083/jcb.202211029 -
Trends in Genetics : TIG Mar 2024Maternal mRNAs accumulate during egg growth and must be judiciously degraded or translated to ensure successful development of mammalian embryos. In this review we... (Review)
Review
Maternal mRNAs accumulate during egg growth and must be judiciously degraded or translated to ensure successful development of mammalian embryos. In this review we integrate recent investigations into pathways controlling rapid degradation of maternal mRNAs during the maternal-to-zygotic transition. Degradation is not indiscriminate, and some mRNAs are selectively protected and rapidly translated after fertilization for reprogramming the zygotic genome during early embryogenesis. Oocyte specific cofactors and pathways have been illustrated to control different futures of maternal mRNAs. We discuss mechanisms that control the fate of maternal mRNAs during late oogenesis and after fertilization. Issues to be resolved in current maternal mRNA research are described, and future research directions are proposed.
Topics: Animals; RNA, Messenger, Stored; Embryonic Development; Oocytes; Oogenesis; Zygote; Gene Expression Regulation, Developmental; Mammals
PubMed: 38262796
DOI: 10.1016/j.tig.2023.12.008 -
Fertility and Sterility Oct 2023To examine the developmental competence of immature oocytes in stimulated cycles, that matured after rescue in vitro maturation (IVM) compared with their sibling...
OBJECTIVE
To examine the developmental competence of immature oocytes in stimulated cycles, that matured after rescue in vitro maturation (IVM) compared with their sibling in vivo matured oocytes.
DESIGN
Retrospective cohort study.
SETTING
IVF clinic.
PATIENTS
A total of 182 patients underwent 200 controlled ovarian stimulation cycles with intracytoplasmic sperm injection cycles in which immature oocytes were retrieved and at least one mature oocyte was obtained through rescue IVM.
INTERVENTION
In vitro culture of immature germinal vesicle (GV) and metaphase I (MI) oocytes, retrieved in stimulated cycles.
MAIN OUTCOME MEASURES
Fertilization rate, cleavage rate, blastulation rate, ploidy of embryos evaluated using preimplantation genetic testing for aneuploidy, morphokinetic parameters and pregnancy outcomes.
RESULTS
In total, 2,288 oocytes were retrieved from 200 cycles. After denudation, 1,056 of the oocytes (46% ± 16%) were classified as metaphase II (MII). A total of 333/375 (89%) of MI oocytes and 292/540 (54%) of GV oocytes matured overnight and underwent intracytoplasmic sperm injection. The fertilization rates of matured oocytes from MI rescue IVM (R-MI) and from GV rescue IVM (R-GV) were comparable with those of their sibling MII oocytes (71% vs. 66%; 66% vs. 63%, respectively). Early cleavage rates (80% ± 35% vs. 92% ± 20%; 80% ± 42% vs. 95% ± 28%, respectively) and blastulation rates (32 ± 40% vs. 62 ± 33%; 24 ± 37% vs. 60 ± 35%, respectively) were significantly decreased in rescue IVM matured oocytes (R-oocytes)-derived zygotes, but the blastocyst (BL) euploidy rate and "good quality" BL rate were comparable with those of MII sibling-derived embryos. In addition, rescue IVM embryos showed significantly higher levels of multinucleation at the 2- and 4-cell stages, as well as higher rates of zygote direct cleavage from one to 3 to 4 cells. Overall, 21 transfers of rescue IVM embryos resulted in 3 healthy live births.
CONCLUSIONS
For patients with a low maturation rate and/or low numbers of mature oocytes at retrieval, rescue IVM may contribute more competent oocytes and additional viable BLs for transfer from the same stimulation cycle, maximizing the chances for pregnancy and live birth.
Topics: Pregnancy; Female; Humans; Male; In Vitro Oocyte Maturation Techniques; Retrospective Studies; Semen; Oocytes; Pregnancy Outcome; Fertilization in Vitro
PubMed: 37257719
DOI: 10.1016/j.fertnstert.2023.05.163 -
DNA and Cell Biology Jun 2024parasites, the causative agents of malaria, rely on sophisticated cellular mechanisms to survive and proliferate within their hosts. complex life cycle requires... (Review)
Review
parasites, the causative agents of malaria, rely on sophisticated cellular mechanisms to survive and proliferate within their hosts. complex life cycle requires posttranslational modifications (PTMs) to control cellular activities. Neddylation is a type of PTM in which NEDD8 is covalently attached to target proteins and plays an important role in cell cycle control and metabolism. Covalent attachment to its substrates requires the Nedd8-activating enzyme, E1; the NEDD8-conjugating enzyme, E2; and the ligase, E3. In , protein neddylation is essential for parasite development during the stage I-II transition from zygote to ookinete differentiation and malaria transmission. Here, we discuss the current understanding of protein neddylation in which is involved in malaria transmission.
PubMed: 38885136
DOI: 10.1089/dna.2024.0120 -
Journal of Assisted Reproduction and... Mar 2024Coenzyme Q10 (CoQ10) is a natural component widely present in the inner membrane of mitochondria. CoQ10 functions as a key cofactor for adenosine triphosphate (ATP)... (Review)
Review
Coenzyme Q10 (CoQ10) is a natural component widely present in the inner membrane of mitochondria. CoQ10 functions as a key cofactor for adenosine triphosphate (ATP) production and exhibits antioxidant properties in vivo. Mitochondria, as the energy supply center of cells, play a crucial role in germ cell maturation and embryonic development, a complicated process of cell division and cellular differentiation that transforms from a single cell (zygote) to a multicellular organism (fetus). Here, we discuss the effects of CoQ10 on oocyte maturation and the important role of CoQ10 in the growth of various organs during different stages of fetal development. These allowed us to gain a deeper understanding of the pathophysiology of embryonic development and the potential role of CoQ10 in improving fertility quality. They also provide a reference for further developing its application in clinical treatments.
Topics: Humans; Ubiquinone; Antioxidants; Mitochondria; Embryonic Development
PubMed: 38372883
DOI: 10.1007/s10815-024-03052-6 -
Environmental Pollution (Barking, Essex... Aug 2023Arsenite is commonly used as an insecticide, antiseptic and herbicide. It can enter the food chain via through soil contamination, and harm human health, including the...
Arsenite is commonly used as an insecticide, antiseptic and herbicide. It can enter the food chain via through soil contamination, and harm human health, including the reproductive systems. Early embryos, as the initial stage of mammalian life, are very sensitive to the environmental toxins and pollutants. However, whether and how arsenite disturbs the early embryo development remains unclear. Our study used mouse early embryos as a model and revealed that arsenite exposure did not cause reactive oxygen species production, DNA damage or apoptosis. However, arsenite exposure arrested embryonic development at the 2-cell stage by altering gene expression patterns. The transcriptional profile in the disrupted embryos showed abnormal maternal-to-zygote transition (MZT). More importantly, arsenite exposure attenuated H3K27ac modification enrichment at the promoter region of Brg1, a key gene for MZT, which inhibited its transcription, and further affected MZT and early embryonic development. In conclusion our study highlights arsenite exposure affects MZT by reducing the enrichment of H3K27ac on the embryonic genome, and ultimately induces early embryonic development arrest at the 2-cell stage.
Topics: Pregnancy; Female; Humans; Animals; Mice; Zygote; Arsenites; Embryonic Development; Mammals; Gene Expression Regulation, Developmental
PubMed: 37211227
DOI: 10.1016/j.envpol.2023.121856