Study On Bmp4 Expression In The Skin And Feather Bud During Embryonic Stage Of Goose

The goose feathers are very useful,especially the downy feathers.The downy feathers have fine warmth retention property and well bulkiness,so they have higher economic value.But for many years,only the effects of some nutrient components to the growth of goose feathers were studied,there was a lack of researches to reveal the molecular mechanism of feather development.Chickens were taken as model animal by foreign scientists,they found that Bmp4 gene had important regulatory effects to the feather development. So a partial cDNA of Bmp4 gene was cloned,and in situ hybridization technique was used to study the expression changes of Bmp4 gene in the skin and feather bud during embryonic stage of goose,and finally, the effects of Bmp4 gene to the goose skin and feather developments were preliminary identified.There were two successive stages in this experiment,and the first one was the analysis of alignment.The total RNA isolated from dorsal skin of goose at E11 was taken as template,and RT-PCR technique was used to amplify a partial cDNA of Bmp4.The cDNA was cloned into pGEM-T easy vector,and then digested by restriction enzyme,and finally sequenced.There were many mutations in the sequence compared to those of Gallus gallus,Rattus norvegicus,Mus musculus,Homo sapiens,and Pan troglodytes.DNAMAN soft was used to make homologic comparison,and the results showed that the homologies were 94.36%,79.69%, 77.85%,78.35%,and 78.35%,respectively.When the nucleotide sequences were translated into amino acid sequences,there were also some difference.The results showed that the homologies were 95.28%,87.04%, 87.96%,87.16%,and 86.24%,respectively.It was guessed that the differences in the sequences caused the morphologic differences between the feathers of poultry and hairs of mammal,and it was also one of the main factors to influence the downy feather formation.The second part was ISH.The linear pGEM-T easy vector linked cDNA of Bmp4 gene was taken as template,and in vitro transcription technique was used to synthesize the digoxigenin-labelled cRNA probe. The dorsal,ventral,and thoracic skins were sampled to make frozen sections when the geese were at E12,E13, and E14.Through pre-hybridization,hybridization,post-hybridization elution,and coloration,the positive parts showed that the expression law were the same among the three body regions,and located just in the epithelial cells.It was guessed that Bmp4 was related to the feather placode formation,feather bud formation and elongation,and further it could influence the branching of feather.It was the first time that a partial cDNA of goose Bmp4 gene was obtained,and it was proposed that Bmp4 gene might be one of the factors which influence the morphologies of feathers and hairs according to the alignment results.In addition,ISH technique was used for the first time to localize the Bmp4 gene expression in the skin and feather bud of goose,and Bmp4 gene might influence the skin and feather formations.