Plant & Animal Genomes XIX Conference

January 15-19, 2011
Town & Country Convention Center
San Diego, CA

Characterization Of Ovarian miRNAs During Pregnancy Of High And Low Prolificacy Sows From An Iberian X Meishan F2 Intercross

Ingrid Balcells¹ , Oriol Timoneda¹ , Susanna Cirera² , Rolf Søkilde³ , Thomas Litman³ , Amanda Fernández-Rodríguez⁴ , Jose Luís Noguera⁵ , Armand Sanchez¹ , Anna Tomàs¹

¹  Departament de Ciència Animal i dels Aliments. Facultat de Veterinària, UAB. Bellaterra, Spain

²  Department of Basic Animal and Veterinary Sciences, Division of Genetics and Bioinformatics, Faculty of Life Sciences, University of Copenhagen, Denmark

³  Biomarker Discovery, Exiqon A/S, Vedbæk, Denmark

⁴  Departamento de Mejora Genética Animal, SGIT-INIA, Madrid, Spain.

⁵  Genètica i Millora Animal, IRTA, Lleida, Spain

Reproductive traits, like prolificacy, are complex traits of economical interest for swine breeders. To better understand the genetic architecture of these traits, an F2 intercross was created between 18 Meishan (Me) sows and 3 Iberian (Ib) boars, breeds that show highly divergent phenotype in prolificacy traits. During pregnancy, the ovarian gene expression is controlled by epigenetic factors, like microRNAs (miRNAs), to ensure a proper synthesis of hormones essential for conceptus maintenance. The aim of this work was to study the ovarian miRNA profile of pregnant sows and to determine whether there are differences in the pattern of miRNA expression which could be attributed to the prolificacy level. Total RNA from six F2 IbxMe sows, classified into two groups according to the number of embryos (NE) at 30-32 days of gestation as high (NE≥16; n=3) or low (NE≤6; n=3) prolificacy, were hybridized on miRCURY™ LNA™ microRNA microarrays (Exiqon) contaning 1891 capture probes targeting miRNAs from human, mouse and rat registered in the miRBASE v14.0. Microarray data was quantile normalized and differential expression was analyzed by dChip software. Ten miRNAs seemed to be differentially expressed between high and low prolificacy sows when a low stringent threshold of significance was used (p-value<0.2). Among these, one miRNA was statistically significant (p-value<0.05): miR-142-3p. This is an interesting miRNA candidate since it has been associated with human endometriosis disease and targets with genes involved in reproductive processes like SLC38A4, PRLR, FMR1, HMGA2 and ARNTL. qPCR analyses are now being performed to validate and quantify these results.