A comprehensive analysis of the human placenta transcriptome

Abstract

As the conduit for nutrients and growth signals, the placenta is critical to establishing an environment sufficient for fetal growth and development. To better understand the mechanisms regulating placental development and gene expression, we characterized the transcriptome of term placenta from 20 healthy women with uncomplicated pregnancies using RNA-seq. To identify genes that were highly expressed and unique to the placenta we compared placental RNA-seq data to data from 7 other tissues (adipose, breast, hear, kidney, liver, lung, and smooth muscle) and identified several genes novel to placental biology (QSOX1, DLG5, and SEMA7A). Semi-quantitative RT-PCR confirmed the RNA-seq results and immunohistochemistry indicated these proteins were highly expressed in the placental syncytium. Additionally, we mined our RNA-seq data to map the relative expression of key developmental gene families (Fox, Sox, Gata, Tead, and Wnt) within the placenta. We identified FOXO4, GATA3, and WNT7A to be amongst the highest expressed members of these families. Overall, these findings provide a new reference for understanding of placental transcriptome and can aid in the identification of novel pathways regulating placenta physiology that may be dysregulated in placental disease.

Evolutionary origins of the placental expression of chromosome 19 cluster galectins and their complex dysregulation in preeclampsia

“…CGA, CGB, CSH1, ERVWE1, HSD3B1 ) expression [72–77], while the L1PA6 TE in the LGALS16 5’UTR is not enriched by these binding sites. In addition, the human LGALS13 , LGALS14 and LGALS16 promoters contain putative binding sites for GATA, TEF-5 and ESRRG, which latter is important in the regulation of trophoblast metabolism [78,79].…”

Morphomics: An integral part of systems biology of the human placenta

“…Transcriptomics embraces the quantitative study of the expression levels of mRNAs utilizing microarray and RNA-seq technologies. The transcriptome of placentas from normal pregnancies has been characterized [15] and significant changes occur in pregnancies compromised by antiphospholipid antibodies [16] and by maternal cigarette smoking [17].…”

Deficiency of the placenta- and yolk sac-specific tristetraprolin family member ZFP36L3 identifies likely mRNA targets and an unexpected link to placental iron metabolism

“…First, it is the only family member (besides ZFP36L3) for which a deficiency is known to cause defects in the mouse placenta, leading to failure of chorioallantoic fusion (Stumpo et al, 2004). Second, deep sequencing experiments have shown that its mRNA levels are the highest of the three family members found in human placenta (Saben et al, 2014). Finally, Zfp36l1 mRNA is the most highly expressed of the family members in the placentas from the rodent Nannospalax galili, a species very close evolutionarily to the rodents that express ZFP36L3, but which apparently does not express ZFP36L3 in the placenta (Gingerich et al, 2016).…”