Molecular characterization and expression profiling of BMP 3 gene in broiler and layer chicken.

A study was carried out to characterize and explore the expression profile of BMP 3 gene in control broiler and control layer chicken. The total open reading frame of BMP 3 (1389 bp) was cloned and sequenced. The control broiler and control layer chicken showed variation at nucleotide and amino acid level with reference gene (Gallus gallus, NCBI Acc. No. NM_001034819). When compared to reference gene, the control broiler showed four nucleotide differences (c.192A>G, c.519C>T, 903G>A and 960C>G), while, control layer showed variation at c.33G>C, 192A>G, 858G>A, 904G>A, 960C>G and 1257C>T making six differences in total. However, between control broiler and control layer lines, nucleotide differences was observed at c.33G>C, 519T>C, 858G>A, 903A>G, 904G>A and 1257C>T. The change at amino acid level between reference and control broiler was p.D320N and with control layer chicken, it was p.D302N and p.D320N. On the other hand, a single amino acid difference (p.D302N) was observed between the control broiler and control layer chicken lines. The phylogenetic study displayed a close relationship between broiler and layer lines and reference gene and also with other avian species resulting in a cluster formation. These cluster in turn displayed a distant link with the mammalian species. The expression profile of BMP 3 gene exhibited a variation at different stages of embryonic development and also at post embryonic period among the lines with control layer showing higher expression than that of broiler chicken. The protein was also detected in bone marrow tissue of broiler and layer lines by western blotting. It is concluded that the BMP 3 gene sequence differed at nucleotide and amino acid level among the lines and the gene expressed differentially at different periods of embryonic development and also at post hatch period.