Histone methyltransferase SMYD3 regulates the expression of transcriptional factors during bovine oocyte maturation and early embryonic development

Cannabis significantly alters DNA methylation of the human ovarian follicle in a concentration-dependent manner

Cannabis is increasingly consumed by women of childbearing age, and the reproductive and epigenetic effects are unknown. The purpose of this study was to evaluate the potential epigenetic implications of cannabis use on the female ovarian follicle. Whole-genome methylation was assessed in granulosa cells from 14 matched case-control patients. Exposure status was determined by liquid chromatography-mass spectrometry (LC-MS/MS) measurements of five cannabis-derived phytocannabinoids in follicular fluid. DNA methylation was measured using the Illumina TruSeq Methyl Capture EPIC kit. Differential methylation, pathway analysis and correlation analysis were performed. We identified 3679 differentially methylated sites, with two-thirds affecting coding genes. A hotspot region on chromosome 9 was associated with two genomic features, a zinc-finger protein (ZFP37) and a long non-coding RNA (FAM225B). There were 2214 differentially methylated genomic features, 19 of which have been previously implicated in cannabis-related epigenetic modifications in other organ systems. Pathway analysis revealed enrichment in G protein-coupled receptor signaling, cellular transport, immune response and proliferation. Applying strict criteria, we identified 71 differentially methylated regions, none of which were previously annotated in this context. Finally, correlation analysis revealed 16 unique genomic features affected by cannabis use in a concentration-dependent manner. Of these, the histone methyltransferases SMYD3 and ZFP37 were hypomethylated, possibly implicating histone modifications as well. Herein, we provide the first DNA methylation profile of human granulosa cells exposed to cannabis. With cannabis increasingly legalized worldwide, further investigation into the heritability and functional consequences of these effects is critical for clinical consultation and for legalization guidelines.

Recurrent Co-Option and Recombination of Cytokine and Three Finger Proteins in Multiple Reproductive Tissues Throughout Salamander Evolution

Reproductive proteins evolve at unparalleled rates, resulting in tremendous diversity of both molecular composition and biochemical function between gametes of different taxonomic clades. To date, the proteomic composition of amphibian gametes is largely a molecular mystery, particularly for Urodeles (salamanders and newts) for which few genomic-scale resources exist. In this study, we provide the first detailed molecular characterization of gametes from two salamander species (Plethodon shermani and Desmognathus ocoee) that are models of reproductive behavior. Long-read PacBio transcriptome sequencing of testis and ovary of both species revealed sex-specific expression of many genes common to vertebrate gametes, including a similar expression profile to the egg coat genes of Xenopus oocytes. In contrast to broad conservation of oocyte genes, major testis transcripts included paralogs of salamander-specific courtship pheromones (PRF, PMF, and SPF) that were confirmed as major sperm proteins by mass spectrometry proteomics. Sperm-specific paralogs of PMF and SPF are likely the most abundant secreted proteins in P. shermani and D. ocoee, respectively. In contrast, sperm PRF lacks a signal peptide and may be expressed in cytoplasm. PRF pheromone genes evolved independently multiple times by repeated gene duplication of sperm PRF genes with signal peptides recovered through recombination with PMF genes. Phylogenetic analysis of courtship pheromones and their sperm paralogs support that each protein family evolved for these two reproductive contexts at distinct evolutionary time points between 17 and 360 million years ago. Our combined phylogenetic, transcriptomic and proteomic analyses of plethodontid reproductive tissues support that the recurrent co-option and recombination of TFPs and cytokine-like proteins have been a novel driving force throughout salamander evolution and reproduction.

The Epigenetics of Gametes and Early Embryos and Potential Long-Range Consequences in Livestock Species-Filling in the Picture With Epigenomic Analyses

The epigenome is dynamic and forged by epigenetic mechanisms, such as DNA methylation, histone modifications, chromatin remodeling, and non-coding RNA species. Increasing lines of evidence support the concept that certain acquired traits are derived from environmental exposure during early embryonic and fetal development, i.e., fetal programming, and can even be "memorized" in the germline as epigenetic information and transmitted to future generations. Advances in technology are now driving the global profiling and precise editing of germline and embryonic epigenomes, thereby improving our understanding of epigenetic regulation and inheritance. These achievements open new avenues for the development of technologies or potential management interventions to counteract adverse conditions or improve performance in livestock species. In this article, we review the epigenetic analyses (DNA methylation, histone modification, chromatin remodeling, and non-coding RNAs) of germ cells and embryos in mammalian livestock species (cattle, sheep, goats, and pigs) and the epigenetic determinants of gamete and embryo viability. We also discuss the effects of parental environmental exposures on the epigenetics of gametes and the early embryo, and evidence for transgenerational inheritance in livestock.

Genes Associated With Chromatin Modification Within the Swine Placenta Are Differentially Expressed Due to Factors Associated With Season

Seasonal reproductive inefficiency is still observed in modern swine facilities. We previously reported global placental methylation activity was reduced from summer breedings and tended to be less from semen collected during cooler periods. The objective of the current study was to evaluate chromatin modification marks within swine placenta in relationship to breeding season, semen collection season, and semen storage. White composite gilts were artificially inseminated in August or January using single-sire semen that was collected during warm or cool periods and stored as either cryopreserved or cooled-extended. Gilts were harvested 45 days post-breeding, and placental samples from the smallest, average, and largest fetus in each litter were collected and stored at −80°C until RNA extraction. An RT² Profiler assay featuring 84 known chromatin modification enzyme targets was performed using placental RNA pooled by litter. Real-time quantitative polymerase chain reaction results were analyzed using the MIXED procedure, and P-values were Hochberg corrected using the MULTTEST procedure in SAS. The complete model included the fixed effects of breeding season (winter or summer), semen collection season (cool or warm), semen storage (cooled-extended or cryopreserved), interactions; boar as repeated effect; and plate as random effect. If interactions were not significant, only the main effects were tested. The genes, ATF2, AURKA, and KDM5B, were different (P < 0.05) by interaction of breeding season, semen collection season, and semen storage. In general, the greatest (P < 0.05) expression was in placentas derived from summer breedings. Expression of AURKA was also influenced by semen collection and storage. Expression of placental KDM5B from winter breedings was also greater (P < 0.05) from semen collected during cool periods. Placental expressions of ASH2L, DNMT3B, ESCO1, HDAC2, ING3, KDM6B, MYSM1, and SMYD3 were greater (P < 0.05) from summer breedings. Increased expressions of known chromatin modification genes, from placentas derived from summer breedings, are likely responsible for differences in gene transcription between summer- or winter-derived placentas.

SMYD3 promotes colon adenocarcinoma (COAD) progression by mediating cell proliferation and apoptosis

Colon adenocarcinoma (COAD) is a type of common malignant tumor originating in the digestive tract. Recently, targeted therapy has had significant effects on the treatment of COAD. However, more effective molecular targets need to be developed. SET and MYND domain-containing protein 3 (SMYD3) is a type of methyltransferase which methylates histone and non-histone proteins. The effects of SMYD3 on cancer progression and metastasis have been widely revealed. However, its possible role in COAD remains unclear. The current study demonstrated that SMYD3 expression was upregulated in human COAD tissues via analyzing the The Cancer Genome Atlas (TCGA) database and the immunohistochemical assays. Furthermore, the expression of SMYD3 was correlated with prognosis and tumor stage (P=0.038) in patients with COAD. Colony formation, MTT, FCM assays and animal assays indicated SMYD3 affected the proliferation, apoptosis and the cell cycle of COAD cells in vitro and promoted tumor growth in mice in vivo. In summary, the results demonstrated the effects of SMYD3 on COAD progression and we hypothesized that SMYD3 is a novel molecular target for COAD treatment.

Erasing gametes to write blastocysts: metabolism as the new player in epigenetic reprogramming

Understanding preimplantation embryonic development is crucial for the improvement of assisted reproductive technologies and animal production. To achieve this goal, it is important to consider that gametes and embryos are highly susceptible to environmental changes. Beyond the metabolic adaptation, the dynamic status imposed during follicular growth and early embryogenesis may create marks that will guide the molecular regulation during prenatal development, and consequently impact the offspring phenotype. In this context, metaboloepigenetics has gained attention, as it investigates the crosstalk between metabolism and molecular control, i.e., how substrates generated by metabolic pathways may also act as players of epigenetic modifications. In this review, we present the main metabolic and epigenetic events of pre-implantation development, and how these systems connect to open possibilities for targeted manipulation of reproductive technologies and animal production systems.

SMYD3: An Oncogenic Driver Targeting Epigenetic Regulation and Signaling Pathways

SMYD3 is a member of the SMYD lysine methylase family and plays an important role in the methylation of various histone and non-histone targets. Aberrant SMYD3 expression contributes to carcinogenesis and SMYD3 upregulation was proposed as a prognostic marker in various solid cancers. Here we summarize SMYD3-mediated regulatory mechanisms, which are implicated in the pathophysiology of cancer, as drivers of distinct oncogenic pathways. We describe SMYD3-dependent mechanisms affecting cancer progression, highlighting SMYD3 interplay with proteins and RNAs involved in the regulation of cancer cell proliferation, migration and invasion. We also address the effectiveness and mechanisms of action for the currently available SMYD3 inhibitors. The findings analyzed herein demonstrate that a complex network of SMYD3-mediated cytoplasmic and nuclear interactions promote oncogenesis across different cancer types. These evidences depict SMYD3 as a modulator of the transcriptional response and of key signaling pathways, orchestrating multiple oncogenic inputs and ultimately, promoting transcriptional reprogramming and tumor transformation. Further insights into the oncogenic role of SMYD3 and its targeting of different synergistic oncogenic signals may be beneficial for effective cancer treatment.

Effects of lipopolysaccharide on maturation of bovine oocyte in vitro and its possible mechanisms

Lipopolysaccharide disturbs the secretion of gonadotropin, endometrial function and implantation efficiency. However, there is little information regarding the effects of lipopolysaccharide on cyclic ovary activity, especially oocyte maturation. Therefore, we aimed to investigate the effects of lipopolysaccharide on the maturation potential of bovine oocytes. We found that lipopolysaccharide exposure significantly decreased the first polar body extrusion rate and delayed the cell cycle progression. The abnormal spindle rate was significantly increased in lipopolysaccharide treatment group, accompanied by disrupted localization and level of phosphorylated mitogen-activated protein kinase (p-MAPK). Moreover, lipopolysaccharide treatment significantly increased intracellular reactive oxygen species (ROS) levels and the early apoptotic rate in oocytes. The pro-apoptotic caspase-3 and Bax mRNA levels and caspase-3 protein level were significantly increased, whereas the anti-apoptotic Bcl-2 and XIAP transcript abundance were significantly decreased in lipopolysaccharide exposure group. Furthermore, the dimethyl-histone H3 lysine 4 (H3K4me2) level was significantly increased, while the DNA methylation (5-mC) and dimethyl-histone H3 lysine 9 (H3K9me2) levels were markedly decreased in oocytes treated with lipopolysaccharide. In conclusion, lipopolysaccharide exposure inhibits the maturation potential of bovine oocytes by affecting cell cycle, cytoskeletal dynamics, oxidative stress, and epigenetic modifications.

Histone lysine methylation and congenital heart disease: From bench to bedside (Review)

Histone post-translational modifications (PTM) as one of the key epigenetic regulatory mechanisms that plays critical role in various biological processes, including regulating chromatin structure dynamics and gene expression. Histone lysine methyltransferase contributes to the establishment and maintenance of differential histone methylation status, which can recognize histone methylated sites and build an association between these modifications and their downstream processes. Recently, it was found that abnormalities in the histone lysine methylation level or pattern may lead to the occurrence of many types of cardiovascular diseases, such as congenital heart disease (CHD). In order to provide new theoretical basis and targets for the treatment of CHD from the view of developmental biology and genetics, this review discusses and elaborates on the association between histone lysine methylation modifications and CHD.

Novel karyotypes of partial monosomy 21 and partial monosomy 1 and underlying etiology

We report two novel karyotypes in the siblings of a Chinese family, 45,XY,der(1)t(1;21)(q44;q21)mat,-21 and 45,XX,der(1)t(1;21)(q44;q21)mat,-21. These karyotypes are the result of unbalanced inheritance of a maternal balanced reciprocal translocation 46,XX,t(1;21)(q44;q21). Both patients share a phenotype of intellectual disability, facial malformation, and infertility. The infertility is manifest by: azoospermia in the brother and recurrent spontaneous abortions (RSA) in the sister. Database search revealed recurrent copy number losses associated with these translocated regions. Here we propose that the partial deletion of the gene SMYD3 is responsible for both the intellectual disability in both patients, as well as the azoospermia in the male patient. Altogether, SMYD3 may be an important candidate gene for future research on male fertility.

Therapeutical potential of deregulated lysine methyltransferase SMYD3 as a safe target for novel anticancer agents

INTRODUCTION

SET and MYND domain containing-3 (SMYD3) is a member of the lysine methyltransferase family of proteins, and plays an important role in the methylation of various histone and non-histone targets. Proper functioning of SMYD3 is very important for the target molecules to determine their different roles in chromatin remodeling, signal transduction and cell cycle control. Due to the abnormal expression of SMYD3 in tumors, it is projected as a prognostic marker in various solid cancers. Areas covered: Here we elaborate on the general information, structure and the pathological role of SMYD3 protein. We summarize the role of SMYD3-mediated protein interactions in oncology pathways, mutational effects and regulation of SMYD3 in specific types of cancer. The efficacy and mechanisms of action of currently available SMYD3 small molecule inhibitors are also addressed. Expert opinion: The findings analyzed herein demonstrate that aberrant levels of SMYD3 protein exert tumorigenic effects by altering the epigenetic regulation of target genes. The partial involvement of SMYD3 in some distinct pathways provides a vital opportunity in targeting cancer effectively with fewer side effects. Further, identification and co-targeting of synergistic oncogenic pathways is suggested, which could provide much more beneficial effects for the treatment of solid cancers.

Incidence of methylated histones H3K4 and H3K79 in cat germinal vesicles is regulated by specific nuclear factors at the acquisition of developmental competence during the folliculogenesis

PURPOSE

This study aims to characterize the regulations of histone methylations, key epigenetic markers of oocyte competence, in germinal vesicle (GV) from different follicles (preantral, early, small, or large antral stage) using the domestic cat model.

METHODS

In Experiment 1, the incidence of H3K4me3 or H3K79me2 was determined in GVs from the diverse follicle stages directly or after exposure to (1) a methyltransferase inhibitor, (2) sonication to fracture the cytoplasmic membranes and wash away the cytoplasmic content, or (3) methyltransferase inhibitor followed by sonication. In Experiment 2, the presence and maintenance of nuclear methyltransferases SMYD3 and DOT1L (regulating H3K4me3 and H3K79me2, respectively) was characterized in separate GV stages before and after sonication. Functionality of GVs from the various follicle stages (with or without transient isolation from the cytoplasm) then was assessed in Experiment 3 by transfer into recipient competent oocytes.

RESULTS

The incidence of histones H3K4me3 and H3K79me2 within the GV were influenced by the cytoplasmic environment at all stages except at the transition to the early antral stage where nuclear regulating factors appeared to be mainly involved. The methyltransferase SMYD3 and DOT1L also appeared tightly bound to the nucleus at that transition. Interestingly, oocytes reconstructed with a GV isolated from the cytoplasm for a prolonged period had the capacity to form an embryo after fertilization which proved that communication between the donor GV and the host cytoplasm (likely including the regulation of epigenetic factors) could be restored.

CONCLUSIONS

Histone methylation apparently becomes regulated by specific nuclear factors at the acquisition of competence during the folliculogenesis and does not seem to be disrupted by prolonged isolation from the surrounding cytoplasm.

Dynamic expression of chromatin modifiers during developmental transitions in mouse preimplantation embryos

During mouse preimplantation development, major changes in cell fate are accompanied by extensive alterations of gene expression programs. Embryos first transition from a maternal to zygotic program and subsequently specify the pluripotent and the trophectodermal cell lineages. These processes are regulated by key transcription factors, likely in cooperation with chromatin modifiers that control histone and DNA methylation. To characterize the spatiotemporal expression of chromatin modifiers in relation to developmental transitions, we performed gene expression profiling of 156 genes in individual oocytes and single blastomeres of developing mouse embryos until the blastocyst stage. More than half of the chromatin modifiers displayed either maternal or zygotic expression. We also detected lineage-specific expression of several modifiers, including Ezh1, Prdm14, Scmh1 and Tet1 underscoring possible roles in cell fate decisions. Members of the SET-domain containing SMYD family showed differential gene expression during preimplantation development. We further observed co-expression of genes with opposing biochemical activities, such as histone methyltransferases and demethylases, suggesting the existence of a dynamic chromatin steady-state during preimplantation development.