title: Characterisation and comparison of lactating mouse and bovine mammary gland miRNomes.
abstract: BACKGROUND
  The mammary gland is a dynamic organ that undergoes important physiological changes during reproductive cycles. Until now, data regarding the characterisation of miRNA in the mammary gland have been scarce and mainly focused on their abnormal expression in breast cancer. Our goal was to characterise the microRNA (miRNA) involved in mechanisms regulating the mammary function, with particular focus on the lactation stage.
  
  
  RESULTS
  Using high-throughput sequencing technology, the exhaustive repertoires of miRNA expressed (miRNome) in mouse and bovine mammary glands during established lactation were identified, characterized and compared. Furthermore, in order to obtain more information on miRNA loading in the RNA-induced silencing complex (RISC), the miRNome was compared with that obtained from RNA associated with the AGO2 protein (AGO2-miRNome) in mouse lactating mammary gland. This study enabled the identification of 164 and 167 miRNA in mouse and bovine, respectively. Among the 30 miRNA most highly expressed in each species, 24 were common to both species and six of them were preferentially highly expressed in lactating than non-lactating mammary gland. The potential functional roles of these 24 miRNA were deduced using DIANA-miRPath software, based on miRNA/mRNA interactions. Moreover, seven putative novel miRNA were identified. Using DAVID analysis, it was concluded that the predicted targets of two of these putative novel miRNA are involved in mammary gland morphogenesis.
  
  
  CONCLUSIONS
  Our study provides an overview of the characteristics of lactating mouse and bovine mammary gland miRNA expression profiles. Moreover, species-conserved miRNA involved in this fundamental biological function were identified. These miRNomes will now be used as references for further studies during which the impact of animal breeding on the miRNA expression will be analysed.
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Le Guillou
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Marthey
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Laloë
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France.
authors.forename: Johann
authors.initials: J
authors.lastname: Laubier
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France; INRA, UMR1213 Herbivores, Saint-Genès Champanelle, France; Clermont Université, VetAgro Sup, UMR1213 Herbivores, Clermont-Ferrand, France.
authors.forename: Lenha
authors.initials: L
authors.lastname: Mobuchon
authors.affiliation: INRA, UMR1213 Herbivores, Saint-Genès Champanelle, France; Clermont Université, VetAgro Sup, UMR1213 Herbivores, Clermont-Ferrand, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Leroux
authors.affiliation: INRA, UMR1313 Génétique Animale et Biologie Intégrative, Jouy-en-Josas, France.
authors.forename: Fabienne
authors.initials: F
authors.lastname: Le Provost
mesh_terms: D000818:Animals; D002417:Cattle; D005260:Female; D006801:Humans; D007774:Lactation; D008321:Mammary Glands, Animal / Q000378:metabolism*; D051379:Mice; D035683:MicroRNAs / Q000378:metabolism*
chemical_list: D035683:MicroRNAs