初次卵裂时间是猪克隆胚胎发育潜能的重要标识  

Timing of The First Zygotic Cleavage as a Developmental Potential Marker for Porcine Cloned Embryos

作　　者：罗学明[1] 肖炜[2] 冯冲[1] 龙川[1] 闫军[1] 薛振华[2] 云鹏[2] 潘登科[1] 

机构地区：[1]中国农业科学院北京畜牧兽医研究所,北京100193 [2]北京市畜牧兽医总站,北京100107

出　　处：《生物化学与生物物理进展》2010年第12期1339-1345,共7页Progress In Biochemistry and Biophysics

基　　金：北京市农业科技项目(20090612);国家高技术研究发展计划(863)(2008AA101003)资助项目~~

摘　　要：初次卵裂时间与哺乳动物胚胎发育潜能有关.比较了不同初次卵裂时间(20～24 h,早期;25～36 h,中期;37～48 h,晚期;20～48 h,对照)的猪孤雌(parthenogenetic,PA)、体细胞核移植(somatic cell nucleartransfer,SCNT)胚胎的囊胚发育率、扩张囊胚发育率和囊胚细胞数,评价其体外发育能力.发现早期卵裂的PA胚胎发育到第6天的囊胚发育率显著高于中期、晚期以及对照组(P<0.05;54.0%vs.19.6%,5.4%,18.7%).扩张囊胚发育率,早裂胚胎同样优于其他组.早期卵裂的SCNT胚胎发育到第6天的囊胚比率高于中期卵裂胚胎(32.2%vs.23.5%),而晚期卵裂胚胎发育到囊胚的比率最低(6.3%).早期卵裂的SCNT胚胎发育到第6天的扩张囊胚比率显著高于其余各组(P<0.05;18.9%vs.5.9%、3.1%、7.4%).囊胚细胞数在早期、中期、晚期三组之间表现出下降趋势.将早期卵裂的SCNT胚胎与未经挑选的对照组胚胎分别进行移植,观察其体内发育能力.移植早裂SCNT胚胎的受体在产仔数和克隆效率上均明显高于未经挑选胚胎的受体(4.7 vs.2.1;3.9%vs.0.9%),说明早裂胚胎着床后具有更强的发育能力.以上结果表明:初次卵裂时间可以作为猪克隆胚胎发育潜能的重要标识,选择早裂的胚胎进行移植,有助于提高克隆效率.Timing of the first zygotic cleavage is related to the developmental potential of mammalian embryos. This phenomenon in porcine parthenogenetically activated （PA） and somatic cell nucleartransfer（SCNT） embryos was documented. In vitro matured pig oocytes were either activated parthenogenetically or microinjected with a somatic cell, followed by electro-fusion. At 24 h post activation（hpa）, PA and SCNT embryos were assessed visually, and cleaved embryos were moved into new culture wells. This process was repeated at 36 hpa or 48 hpa. Embryos in different groups were allowed to develop for 6 days in culture. The relationship between embryo developmental competence and the first zygotic cleavage at different timing （early-cleaving, 20 ～24 h; mid-cleaving, 25 ～36 h; late-cleaving, 37 ～48 h and unselected controls, 20 ～48 h） was evaluated by the proportions of cleaved embryos developed to blastocysts and expanded blastocysts （EB）, and blastocyst total cell number. For PA embryos, the proportion of early-cleaving embryos that developed to blastocysts was significantly higher than that of mid-cleaving, late-cleaving and controls （P 〈 0.05; 54.0% vs. 19.6%, 5.4% and 18.7%, respectively）; a similar pattern was noted for the formation of EB. For SCNT embryos, the proportion of early-cleaving embryos developing to blastocysts was not significantly higher than that of mid-cleaving embryos （32.2% vs. 23.5%）, but the late-cleaving embryos had poor developmental competence to blastocysts （6.3%）. Early-cleaving SCNT embryos showed a significant higher competence developing to expanded blastocysts than the mid-, late-cleaving and unselected control embryos （P 〈 0.05; 18.9%vs. 5.9%, 3.1%, 7.4%, respectively）. Total cell number in the blastocysts declined across the three cleavage-timed groups. Developmental potential of SCNT cloned embryos was assessed in vivo by transferring early-cleaving （〈 24 h） and unselected （time of cleavage up to 48 h not determined） embryos into re

关 键 词：猪 体细胞核移植 初次卵裂时间 发育潜能 

分 类 号：Q813.7[生物学—生物工程]