title: miR-143 regulation of prostaglandin-endoperoxidase synthase 2 in the amnion: implications for human parturition at term.
abstract: BACKGROUND
  The human amnion plays a pivotal role in parturition. Two of its compartments, the placental amnion and the reflected amnion, have distinct transcriptome and are functionally coordinated for parturition. This study was conducted to determine the microRNA (miRNA) expression pattern and its significance in the placental amnion and the reflected amnion in association with labor at term.
  
  
  RESULTS
  MicroRNA microarray, real-time quantitative RT-PCR (qRT-PCR), and miRNA in situ hybridization analyses of the placental amnion and the reflected amnion (n = 20) obtained at term were conducted. Luciferase assay, transfection, and qRT-PCR analyses of primary amnion epithelial cells (AECs) and amnion mesenchymal cells (AMCs) were performed. MicroRNA microarray analysis demonstrated differential expression of 32 miRNAs between the placental amnion and the reflected amnion after labor. Thirty-one (97%) miRNAs, which included miR-143 and miR-145, a cardiovascular-specific miRNA cluster, were down-regulated in the reflected amnion. Analyses of miR-143 and miR-145 by qRT-PCR confirmed microarray results, and further demonstrated their decreased expression in the reflected amnion with labor. Interestingly, expression of miR-143 and miR-145 was higher in AMCs than in AECs (p<0.05). Luciferase assay and transfection confirmed miR-143 binding to 3' UTR of prostaglandin-endoperoxidase synthase 2 (PTGS2) mRNA and miR-143 regulation of PTGS2 in AMCs.
  
  
  CONCLUSIONS
  We report region-specific amniotic microRNAome and miR-143 regulation of PTGS2 in the context of human labor at term for the first time. The findings indicate that miRNA-mediated post-transcriptional regulation of gene expression machinery in the amnion plays an important role in the compartments (placental amnion vs reflected amnion) and in a cell type-specific manner (AECs vs AMCs) for parturition.
authors.affiliation: Perinatology Research Branch, National Institute of Child Health and Human Development/National Institutes of Health/Department of Health and Human Services, Bethesda, Maryland, United States of America.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Adi L
authors.initials: AL
authors.lastname: Tarca
authors.forename: Gaurav
authors.initials: G
authors.lastname: Bhatti
authors.forename: JoonHo
authors.initials: J
authors.lastname: Lee
authors.forename: Tinnakorn
authors.initials: T
authors.lastname: Chaiworapongsa
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Hassan
authors.forename: Chong Jai
authors.initials: CJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000650:Amnion / Q000378:metabolism*; D051546:Cyclooxygenase 2 / Q000235:genetics*; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D066298:In Vitro Techniques; D035683:MicroRNAs / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D036801:Parturition / Q000235:genetics / Q000378:metabolism*; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction; D055815:Young Adult
chemical_list: D035683:MicroRNAs; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human