The Revelation Of Human CircRNA Expression Profile And Functional Analysis During Placenta Development

Circular RNAs are unique non-coding transcripts,which can be produced from 10%coding genes in cells and tissues,according to reports.Next-generation RNA sequencing(RNA-seq)of non-polyadenylated transcriptomes has recently shown that the expression of circRNA is widespread.CircRNA has become a popstar around the scientific community after miRNA and lncRNA due to its stability,conservation and tissue-specific feature.Recent findings have also shown the regulation roles of circRNAs in cancer and stem cell.Placenta is a temporary organ formed at the very beginning of mammals'pregnancy,where mother exchanges materials and nutrition with fetal,and plays important role during embryonic development.Abnormal development of placenta may cause various pregnancy illness including Preeclampsia and Placenta increta.However,the exact pathogenesis of these diseases is unresolved.We can't help to wonder how circRNAs expressed during embryonic development and if the expression of circRNAs is different between healthy and pathological placenta.Here,by using Next-generation sequence and cell culture assay,we tried to get differential and functional circRNAs between healthy and pathological placenta,and explore the applications of these circRNAs in pregnant women's peripheral blood detection.From healthy(first trimester,second trimester,third trimester)placentas and pathological placentas,we established a series of maps of circRNAs and found out large amounts of circRNAs differentially expressed between healthy and pathological placentas.In addition,we uncovered 98 circRNAs upregulated and 423 circRNAs downregulated in preeclampsia placentas,712 circRNAs upregulated and 98 circRNAs downregulated in placenta increta placentas,compared to healthy placentas.Besides,host genes of these differentially expressed circRNA are closely related to placenta development,which suggests that differentially expressed circRNAs might also be related to regulation of placenta development.Next we conducted wound healing experiment to evalute the effect of circRNA in cell migration ability,and found cells overexpressed differentially expressed circRNAs migrate faster,which is consistent with that circRNAs are differentially expressed in preeclampsia placenta.We also explored the detection of differentially expressed circRNA in peripheral blood but failed.