Expression of antisense of insulin-like growth factor-2 receptor RNA non-coding (AIRN) during early gestation in cattle.

The insulin-like growth factor type 2 receptor (IGF2R) regulates fetal growth by removing IGF2 from circulation. In mice, expression of the Igf2r gene is only imprinted after implantation and is associated with expression of the antisense non-coding (nc)RNA, Airn. The objectives of this study were, first, to determine if bovine AIRN was expressed during developmentally important stages of gestation, and second, to determine if expression of bAIRN was affected by method of embryo production. Control reactions confirmed that sequence verified bAIRN PCR amplicons resulted from RNA within the sample and not from genomic DNA contamination. IGF2R mRNA was expressed in all fetal liver samples at Days 35-55 and 70 of gestation as well as in 8 of 9 Day 15 conceptuses, 10 of 10 Day 18 conceptuses, and in all day 7 blastocyst pools. bAIRN was expressed in all samples of fetal liver at Days 35-55 and 70 of gestation. The proportion of conceptuses that expressed bAIRN increased from 1 of 9 at Day 15 of gestation to 8 of 10 at Day 18 of gestation. No bAIRN was expressed in any blastocyst pools. The relative level of bAIRN was greater (P<0.05) in fetal liver from embryos produced in vivo compared to that from embryos produced in vitro. In summary bAIRN was not expressed in blastocyst-stage embryos, was expressed in an increasing proportion of embryos around the time of maternal recognition of pregnancy and was expressed following implantation. Furthermore, relative levels of bAIRN in bovine fetal liver can be altered by method of embryo production.

Transcriptional profiling of human placentas from pregnancies complicated by preeclampsia reveals disregulation of sialic acid acetylesterase and immune signalling pathways.

The placenta plays an important role as a regulator of fetal nutrition and growth throughout development and placental factors contribute to gestational abnormalities such as preeclampsia. This study describes the genome-wide gene expression profiles of a large (n = 60) set of human placentas in order to uncover gene expression patterns associated with preeclampsia. In addition to confirming changes in expression of soluble factors associated with preeclampsia such as sFLT1 (soluble fms-like tyrosine kinase-1), sENG (soluble endoglin), and INHA (inhibin alpha), we also find changes in immune-associated signaling pathways, offering a potential upstream explanation for the shallow trophoblast invasion and inadequate uterine remodeling typically observed in pathogenesis of preeclampsia. Notably, we also find evidence of preeclampsia-associated placental upregulation of sialic acid acetylesterase (SIAE), a gene functionally associated with autoimmune diseases.

Functional genomic approaches for the study of fetal/placental development in swine with special emphasis on imprinted genes.

This chapter describes the application of functional genomic approaches to the study of imprinted genes in swine. While there are varied definitions of "functional genomics", in general they focus on the application of DNA microarrays, single nucleotide polymorphism (SNP) arrays, and other high coverage genomic analyses, and their combination with downstream methods of gene modification such as silencing RNA (siRNA) and viral and non-viral transfection. Between the initial data acquisition and the actual genetic manipulation of the system lies bioinformatics, where massive amounts of data are analyzed to extract meaningful information. This area is in constant flux with an increased emphasis on detection of affected pathways and processes rather than generation of simple affected gene lists. We will expand on each of these points and describe how we have used these technologies for the study of imprinted genes in swine. First we will introduce the biological question to provide context for the discussion of the functional genomic approaches and the types of information they generate.