The Transcriptional Landscape Of Natural Developmental Magnum In Chickens

The chicken oviduct is an important reproductive organ of both theoretical significance and commercial value. Magnum, as the longest region of the avain oviduct, is the place where layers of eggwhite are deposited around the yolk, and has important research value. This dissertation is aimed at studying the transcriptome change of chicken magnum during normal development. By this study, we could investigate the molecular mechanism of magnum differentiation and regulatory factor functioning during eggwhite formation which can lay a foundation for improvement of egg freshness.In this study, taking White Leghorn chicken as research object, we divided the whole development of chicken oviduct to five stages. They were the lag phase (D1), early proliferation phase (D2), latter proliferation phase (D3), early differentiation phase (D4) and laying phase (L). For our research population, the chickens were in7,13,16,17and20weeks old, respectively. Magnum in each stage was sampled to obtain the whole transcriptome using illumina HiSeq2000technique.17,935transcripts were detected expressed in the magnum. The differentially expressed genes (DEGs) were classified into14bins according to their expression patterns and were used to conduct the functional enrichment analysis. Different GO (Gene Ontology) terms were categorized for each pattern including cell proliferation and regulation, regulation of RNA metabolic process, blood vessel development, amino acid transport and so on. Totally, we got473genes related to cell morphogenesis process which could be the important candidate genes in the magnum development. In addition, four genes(Growth/differentiation factor8; Ovalbumin; HEP21protein and a novel chicken gene ENSGALG00000019851) of different expression patterns were validated by qRT-PCR (Quantitative real-time polymerase chain reaction). Growth/differentiation factor8has an inhibiting effect during magnum development, Ovalbumin may be used as an candidate marker of magnum differentiation and HEP21and as eggwhite constituent proteins, may also participate in oviduct development. By comparing the stage-specific expressed genes, we provided a gene pool which might be selected as the candidate markers to distinguish the different magnum development stages. In all, the vast amount of gene expression data provided us a comprehensive view about the transcriptomes of natural developmental chicken magnum. Our study could help to advance our understanding about the mechanisms of cell development and provide basic information for further studies.