Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNP A2/B1) have a important role in influence of pre-messenger RNA (pre-mRNA) processing and mRNA metabolism and transportation in cells. Recently, hnRNP A2/B1 can recognize m6A modifications on pre-mRNA or pre-miRNA and affect alternative splicing and miRNA processing in HeLa Cells. However, roles of hnRNP A2/B1 in various cells and tissues, especially in elary embryo development, are unclear. Here, we investigated the temporal and spatial expression patterns of hnRNPA2B13 during mammalian early embryo development. In mouse, hnRNPA2B1 was localized at the nucleus after 1-cell stage, however, hnRNPA2B1 was expressed after 2-cell stage in pig. Then, knockdown of hnRNP A2/B1 induced by RNA interference (RNAi) was used to analyze the effect of hnRNP A2/B1 in preimplantation develop in pigs. Knockdown of hnRNP A2/B1 delayed embryo development. Interestingly, ICM marker OCT4 and Sox2 was significantly decreased in blastocyst stage. mRNA expression show that transcription factors which is Pou5f1, Sox2, Nanog, Cdx2 and AP2γwas decreased the transcription levels without the changing of junction protein, ZO-1, occludin, and CXADR. Outgrowth results indicated that knock-down of hnRNPA2B1 embryos cannot format the colony. Knock-down of Methyltransferase like 3(METTL3) embryos mislocalized the hnRNPA2/B1 at the nucleus. In summary, the expression patterns of hnRNPA2/B1 differ between mouse and porcine embryos, and these differences may reflect species-specific functions during preimplantation embryo development. Our results suggested that hnRNPA2/B1 is necessary for newly synthesis of mRNA related with transcription factor, and early embryo development by the RNA epigenetic modification.

• JeongWoo Kwon(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Suk Namgoong(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Xiang-Shun Cui(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Nam-Hyung Kim(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)