%0 Journal Article
%T Identification and characterization of miRNAs expressed in the bovine ovary
%A Md Hossain
%A Nasser Ghanem
%A Michael Hoelker
%A Franca Rings
%A Chirawath Phatsara
%A Ernst Tholen
%A Karl Schellander
%A Dawit Tesfaye
%J BMC Genomics
%D 2009
%I BioMed Central
%R 10.1186/1471-2164-10-443
%X The miRNA library (5'-independent ligation cloning method), which was constructed from bovine ovary in this study, revealed cloning of 50 known and 24 novel miRNAs. Among all identified miRNAs, 38 were found to be new for bovine and were derived from 43 distinct loci showing characteristic secondary structure. While 22 miRNAs precursor loci were found to be well conserved in more than one species, 16 were found to be bovine specific. Most of the miRNAs were cloned multiple times, in which let-7a, let-7b, let-7c, miR-21, miR-23b, miR-24, miR-27a, miR-126 and miR-143 were cloned 10, 28, 13, 4, 11, 7, 6, 4 and 11 times, respectively. Expression analysis of all new and some annotated miRNAs in different intra-ovarian structures and in other multiple tissues showed that some were present ubiquitously while others were differentially expressed among different tissue types. Bta-miR-29a was localized in the follicular cells at different developmental stages in the cyclic ovary. Bio-informatics prediction, screening and Gene Ontology analysis of miRNAs targets identified several biological processes and pathways underlying the ovarian function.Results of this study suggest the presence of miRNAs in the bovine ovary, thereby elucidate their potential role in regulating diverse molecular and physiological pathways underlying the ovarian functionality. This information will give insights into bovine ovarian miRNAs, which can be further characterized for their role in follicular development and female fertility as well.Folliculogenesis is the result of series of complex and coordinated processes, which include morphological and functional changes in different types of follicular cells and their interactions. Sequential recruitment, selection and growth of the follicles, atresia, ovulation and luteolysis are dynamically regulated events that occur on a cyclical basis within the ovary. These processes are under control of closely coordinated endocrine and paracrine factors to deve
%U http://www.biomedcentral.com/1471-2164/10/443