Redel Bethany K, Tessanne Kimberly J, Spate Lee D, Murphy Clifton N, Prather Randall S
Division of Animal Science, Animal Science Research Center, 920 East Campus Drive, Columbia, MO 65211, USA.
Reprod Fertil Dev. 2015 May;27(4):655-66. doi: 10.1071/RD14293.
Culture systems promote development at rates lower than the in vivo environment. Here, we evaluated the embryo's transcriptome to determine what the embryo needs during development. A previous mRNA sequencing endeavour found upregulation of solute carrier family 7 (cationic amino acid transporter, y+ system), member 1 (SLC7A1), an arginine transporter, in in vitro- compared with in vivo-cultured embryos. In the present study, we added different concentrations of arginine to our culture medium to meet the needs of the porcine embryo. Increasing arginine from 0.12 to 1.69mM improved the number of embryos that developed to the blastocyst stage. These blastocysts also had more total nuclei compared with controls and, specifically, more trophectoderm nuclei. Embryos cultured in 1.69mM arginine had lower SLC7A1 levels and a higher abundance of messages involved with glycolysis (hexokinase 1, hexokinase 2 and glutamic pyruvate transaminase (alanine aminotransferase) 2) and decreased expression of genes involved with blocking the tricarboxylic acid cycle (pyruvate dehydrogenase kinase, isozyme 1) and the pentose phosphate pathway (transaldolase 1). Expression of the protein arginine methyltransferase (PRMT) genes PRMT1, PRMT3 and PRMT5 throughout development was not affected by arginine. However, the dimethylarginine dimethylaminohydrolase 1 (DDAH1) and DDAH2 message was found to be differentially regulated through development, and the DDAH2 protein was localised to the nuclei of blastocysts. Arginine has a positive effect on preimplantation development and may be affecting the nitric oxide-DDAH-PRMT axis.
培养系统促进胚胎发育的速度低于体内环境。在此，我们评估了胚胎的转录组，以确定胚胎在发育过程中需要什么。之前的一项mRNA测序研究发现，与体内培养的胚胎相比，体外培养的胚胎中溶质载体家族7（阳离子氨基酸转运体，y+系统）成员1（SLC7A1，一种精氨酸转运体）上调。在本研究中，我们在培养基中添加了不同浓度的精氨酸，以满足猪胚胎的需求。将精氨酸浓度从0.12mM提高到1.69mM可增加发育到囊胚阶段的胚胎数量。与对照组相比，这些囊胚的总细胞核更多，特别是滋养外胚层细胞核更多。在1.69mM精氨酸中培养的胚胎SLC7A1水平较低，与糖酵解相关的信使RNA丰度较高（己糖激酶1、己糖激酶2和谷丙转氨酶（丙氨酸转氨酶）2），参与阻断三羧酸循环（丙酮酸脱氢酶激酶，同工酶1）和磷酸戊糖途径（转醛醇酶1）的基因表达降低。精氨酸甲基转移酶（PRMT）基因PRMT1、PRMT3和PRMT5在整个发育过程中的表达不受精氨酸影响。然而，发现二甲基精氨酸二甲胺水解酶1（DDAH1）和DDAH2的信使RNA在发育过程中受到差异调节，并且DDAH2蛋白定位于囊胚细胞核。精氨酸对植入前发育有积极影响，可能影响一氧化氮-DDAH-PRMT轴。
