CAJ | 학술논문

克隆动物胎盘发育缺陷是造成动物克隆效率低下的一个重要原因。目前认为克隆胎盘发育异常通常是由于一些基因表达的异常所致,与表观遗传修饰有关。microRNA是一种重要的表观遗传修饰方式,对动物胚胎发育和胎盘的形成有着重要的调控作用。为研究miR-127和miR-136在克隆动物胎盘中的表达情况及其与克隆动物发育缺陷的关系,本实验运用荧光定量PCR分析了死亡克隆绵羊胎盘和同期普通绵羊胎盘组织中miR-127和miR-136的相对表达量,并鉴定了miR-127和miR-136的靶基因及靶基因在胎盘中的表达情况。结果显示,miR-127和miR-136在克隆绵羊胎盘中的表达量分别增加了3.1和2.8倍。EGFP荧光敲除实验证实,胎盘发育相关基因Rtl1是miR-127和miR-136的靶基因,同时定量PCR分析发现Rtl1基因在克隆绵羊胎盘中的表达量降低了3/5。结果说明,miR-127和miR-136在克隆胎盘中的异常表达可导致Rtl1基因的低表达,这很可能是导致克隆动物死亡的一个重要原因。
극륭동물태반발육결함시조성동물극륭효솔저하적일개중요원인。목전인위극륭태반발육이상통상시유우일사기인표체적이상소치,여표관유전수식유관。microRNA시일충중요적표관유전수식방식,대동물배태발육화태반적형성유착중요적조공작용。위연구miR-127화miR-136재극륭동물태반중적표체정황급기여극륭동물발육결함적관계,본실험운용형광정량PCR분석료사망극륭면양태반화동기보통면양태반조직중miR-127화miR-136적상대표체량,병감정료miR-127화miR-136적파기인급파기인재태반중적표체정황。결과현시,miR-127화miR-136재극륭면양태반중적표체량분별증가료3.1화2.8배。EGFP형광고제실험증실,태반발육상관기인Rtl1시miR-127화miR-136적파기인,동시정량PCR분석발현Rtl1기인재극륭면양태반중적표체량강저료3/5。결과설명,miR-127화miR-136재극륭태반중적이상표체가도치Rtl1기인적저표체,저흔가능시도치극륭동물사망적일개중요원인。
Abnormal development of cloned animal placenta is one of the main causes of the low efficiency of somatic cell nuclear transfer（SCNT）,which was caused by abnormal gene expession and involved in epigenetic modification of the genome.microRNA is a major epigenetic modification of the genome and plays a crucial role in animal embryo and placenta development.However,the expression and function of microRNA in cloned placenta has not been reported.In order to study the correlation between expression of miR-127 and miR-136 in cloned placenta development and the development abnormality of cloned sheep,expression of miR-127 and miR-136 in placenta of the dead cloned sheep fetus and the age-matched normal sheep fetus（control）were detected by using real time PCR,and targets of miR-127 and miR-136 were tested by using EGFP fluorescence reporting system.Results indicated that expression levels of miR-127 and miR-136 in cloned sheep placenta were 3.1 and 2.8 times more than that of normal sheep placenta.EGFP fluorescence knockdown assay confirmed that Rtl1 was the target of miR-127 and miR-136.Moreover,expression levels of Rtl1 in cloned sheep placenta were 2.5 time less than that of normal sheep placenta.These finding suggested that abnormal expression of miR-127 and miR-136 resulted in down-regulation of Rtl1 expression,which may be one of the main causes of death of the transgenic cloned animal.