The perturbed expression of m6A in parthenogenetic mouse embryos

Abstract

Parthenogenetically activated oocytes cannot develop to term in mammals owing to abnormal epigenetic modifications. Methylation of the N6 position of adenosine (m6A) is a post-transcriptional epigenetic modification of RNA. To investigate the role of m6A methylation in parthenogenetic (PA) embryonic development, we analyzed METTL3, METTL14, FTO, ALKBH5, YTHDF2, IGF2BP1, and IGF2BP2 expression by quantitative real-time PCR. These genes were found dynamically expressed during the 2-cell, 4-cell, 8-cell, and blastocyst stages of the embryo. Compared to normally fertilized embryos, the expression of these genes was perturbed in PA embryos, especially at the 8-cell stage. Furthermore, immunofluorescence was used to detect m6A expression. The results demonstrated that m6A expression decreased in the 2-cell stage, whereas it increased in the 8-cell stage of PA embryos. Taken together, these results suggest that the expression of RNA methylation-related genes was perturbed, leading to abnormal m6A modification during early development in PA embryos.

Role of N6-methyl-adenosine modification in mammalian embryonic development

“…Increasing data have demonstrated that RNA modification is a dynamic process involved in the regulation of a variety of physiological processes (Motorin and Helm, 2011;Chan et al, 2012;Meyer and Jaffrey, 2014;Kirchner and Ignatova, 2015). Our previous data confirmed that m6A modification is a dynamic process that occurs during mouse embryonic development (Hao et al, 2019). This finding indicated that the methylation status of m6A was dynamically regulated by m6A-related genes during embryonic development (Faulds et al, 2018).…”

m6A methylated EphA2 and VEGFA through IGF2BP2/3 regulation promotes vasculogenic mimicry in colorectal cancer via PI3K/AKT and ERK1/2 signaling

“…The function of m6A modification is determined by writers, erasers and readers, and the abnormality of its regulation mechanism is related to cancer [ 23 , 26 , 27 ]. In order to reveal the role of m6A modification in CRC, the gene expressions of m6A binding proteins were compared by RNA-seq in TCGA.…”

“…“Eraser” demethylases (e.g., FTO, ALKBH5, and ALKBH3) can remove the m6A modification, and the m6A residue can be recognized by “readers” (e.g., YTHDC1/2, YTHDF1/2/3, IGF2BP1/2/3, HNRNP, and eIF3) [ 23 ]. m6A plays important roles in mRNA stabilization, splicing, degradation, and translation efficiency via altering target gene expression [ 24 , 25 ], and its function has been explored in various biological processes, including stem cell differentiation [ 26 ], embryonic development [ 27 ], DNA damage [ 28 ], and tumor progression [ 23 ], among others. As an important m6A regulator enzyme, the methyltransferase, METTL3, can promote tumor progression by regulating downstream target genes in leukemia [ 29 ], colorectal cancer [ 30 , 31 ], bladder cancer [ 32 ], and gastric cancer [ 33 ]; however, the relationship between the m6A writer, METTL3, and VM formation remains unclear.…”

Procyanidin B1 promotes in vitro maturation of pig oocytes by reducing oxidative stress

“…Immunofluorescence (IF) staining is an important method for measuring protein expression in embryos, and has been used in our previous studies (Gao et al, 2019; Hao et al, 2019; Liang et al, 2017; Yuan et al, 2017) and other related studies (Amouroux et al, 2016; Inoue & Zhang, 2011; Sakashita et al, 2014). To detect expression of apoptotic proteins in MII oocytes by IF staining in this study, we analyzed the P53 level of 21 MII oocytes of 100 μM PB1 group and 21 MII oocytes of control group, the caspase‐3 level of 24 MII oocytes of 100 μM PB1 group and 23 MII oocytes of control group.…”