Profiling Of Feather Follicle MicroRNAs And Expression Level Of Related Genes During Embryonic Periods Of Cherry Valley Duck

Downy trait is one of the most important economic traits in ducks.Genetic plays important role in feather development that is regulated by many factors.It is well known that miRNA exert its function through regulating correlated gene expression and thus affects feather growth.In the present study,we focused on the analysis of miRNAs expression profiles of feather development during the incubation periods of Cherry Valley duck.A total of four incubation periods,including embryo 11,15,20,and 1d posthatch(E11,E15,E20,and 1d),with 3 samples per period for expression profile analysis,and 8 samples per period for miRNA and gene expression analysis.The correlation between miRNAs expression and related genes was conducted using SAS9.4 simple correlation process.The results showed 337 known miRNAs and 93 novel candidate mi RNAs based oncomparisons with known miRNAs in the Gallus gallus miRBase.The series of miRNAs related to feather formation exhibited eight expression patterns.Analysis of miRNAs expression profiles identified 7 highly expressed miRNAs,which might be directly responsible for regulation of feather development.The Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis using the 7 highly expressed mi RNAs suggested that 12 signaling pathways including Notch signaling pathway,Glycerolipid metabolism,etc,participating in the formation of feather.These suggested that in addition to the wide accepted signaling pathway that control feather growth,another group of signaling pathways that regulate lipid synthesis and metabolism should be paid much attention for their responsibility of feather quality.To verify the expression data,two miRNAs in known database and one from novel miRNAs with varying expression levels were selected for qRT-PCR expressio n analysis,indicating high consistency with previous expression profiles.The Pearso n's correlation coefficients(r-values)of the 3 selected mi RNAs and related genes(Fzd3,Wnt8 a,Lrp6,and Birc6)were calculated.The higher expression of miR-30a-5p was associated with lower expression of Fzd3(r=-0.663,P=0.0004).Higher expr ession of miR-203 a was associated with lower expression of Fzd3(r=-0.640,P=0.0008).In addition,higher expression of gga-miR-new-20 was associated with lower ex pression of Wnt8a(r=-0.421,P=0.040)and Birc6(r=-0.778,P <0.0001).It is clear that the Wnt signaling pathway participated in regulation of feather follicle development during the early embryonic period.