Project description:Whole-transcriptome profiles of individual human placental villi samples from twenty-five (25) Indian women with normal pregnancies during 6- to 8-weeks of gestation were examined using human whole genome expression arrays (NimbleGen 135K). The present study focused on the whole-transcriptome profiling using NimbleGen135K (070925_HG18_exp__12X135K) human whole genome expression arrays of individual human placental villi samples obtained from twenty-five (25) proven-fertile women bearing normal pregnancies voluntarily terminated between 6- and 8-weeks of gestation. Gestational age was estimated from menstrual history, physical and ultrasonographic evaluation. No case of complicated pregnancy from infection, and other significant fetal and maternal clinical indications was included. These twenty five (25) samples include biological replicates of 6, 7 and 8 weeks placental villi samples.
Project description:Whole-transcriptome profiles of individual human placental villi samples from twenty-five (25) Indian women with normal pregnancies during 6- to 8-weeks of gestation were examined using human whole genome expression arrays (NimbleGen 135K).
Project description:The goal of this study was to conduct an in-depth analysis of the human placental transcriptome. RNA was extracted from 16 placental samples using TRIzol following the manufacturer’s protocol. All samples were spiked with 96 External RNA Controls Consortium (ERCC) ExFold RNA transcripts. Ribosomal RNAs were depleted from samples using Ribo-Zero Gold and sequencing libraries were prepared using Illumina TruSeq Stranded Total RNA Sample Preparation kits. Sequencing was performed on the Illumina Hi-Seq 2500 using a 100bp paired-end protocol. Sequence adapters were trimmed using AdapterRemoval with options --trimns, --minlength 20. Trimmed RNA-Seq reads were aligned to known UCSC hg19 genes and the hg19 genome using Bowtie 2 v2.1.0 and TopHat v2.0.9 with options --library-type=fr-firststrand --mate-inner-dist -20 --mate-std-dev 180. UCSC hg19 reference genome and transcriptome was obtained through Illumina iGenomes (https://support.illumina.com/sequencing/sequencing_software/igenome.html). Aligned RNA-Seq reads were summarised using the summarizeOverlaps algorithm with the UCSC known genes hg19 GTF file using the the options overlapMode=``Union'', ignoreStrand=FALSE, singleEnd=FALSE, fragments=TRUE to generate a table of unique read counts per gene for each sample. All samples were processed in the same way, with all sequencing libraries created in the same batch and sequenced together.
Project description:Background: Gene expression variation is a phenotypic trait of particular interest as it represents the initial link between genotype and other phenotypes. Analyzing how such variation apportions among and within groups allows for the evaluation of how genetic and environmental factors influence such traits. It also provides opportunities to identify genes and pathways that may have been influenced by non-neutral processes. Here we use a population genetics framework and next generation sequencing to evaluate how gene expression variation is apportioned among four human groups in a natural biological tissue, the placenta. Results: We estimate that on average, 33.2%, 58.9% and 7.8% of the placental transcriptome is explained by variation within individuals, among individuals and among human groups, respectively. Additionally, when technical and biological traits are included in models of gene expression they account for roughly 2% of total gene expression variation. Notably, the variation that is significantly different among groups is enriched in biological pathways associated with immune response, cell signaling and metabolism. Many biological traits demonstrated correlated changes in expression in numerous pathways of potential interest to clinicians and evolutionary biologists. Finally, we estimate that the majority of the human placental transcriptome (65% of expressed genes) exhibits expression profiles consistent with neutrality; the remainder are consistent with stabilizing selection (26%), directional selection (4.9%), or diversifying selection (4.8%). Conclusion: We apportion placental gene expression variation into individual, population and biological trait factors and identify how each influence the transcriptome. Additionally, we advance methods to associate expression profiles with different forms of selection. Placental mRNA was sequenced on an Illumina GAIIx. Samples were derived from 4 human groups, 10 individuals per group, 2 samples per individual
Project description:The purpose of the experiment was to compare placental transcriptome of rhesus macaque at approximately 80% completed gestation to human placental transcriptomes.
Project description:An important question for the use of the mouse as a model for studying human disease is the degree of functional conservation of genetic control pathways from human to mouse. The human and mouse placenta show structural similarities but there have been no systematic attempt to assess their molecular similarities or differences. We built a comprehensive database of protein and microarray data for the highly vascular exchange region micro-dissected from the human and mouse placenta near-term. Abnormalities in this region are associated with two of the most common and serious complications of human pregnancy, maternal preeclampsia (PE) and fetal intrauterine growth restriction (IUGR), each disorder affecting ~5% of all pregnancies. Over 7,000 orthologs were detected with 70% co-expressed and over 80% of genes known to cause placental phenotypes in mouse were co-expressed. These genes form a tight protein-protein interaction network with novel candidate genes likely to be important in placental structure and/or function. The entire data is available as a web-accessible database to guide the informed development of mouse models to study human disease This experiment is now fully represented in NCBI Peptidome database with accession PSE115; http://www.ncbi.nlm.nih.gov/peptidome/search/index.shtml?acc=PSE115 Microdissection of human villous trees and mouse placental labyrinth. Tissues were split for microarray and protein analysis. For protein analysis samples were first fractionated by differential sucrose gradients into mitochrondria, cytosol, microsomes and nuclei. Mitochrondira and neuclei were each extracted by two different methods for soluble and insoluble material. Each subcellular fraction for each tissue was analysed in quintuplet by 9 step 2 dimensional LC/MSMS. This generated a total of 270 mzXML files for each tissue.