Functional analysis of the bovine beta- and kappa casein gene promoters using homologous mammary gland derived cell line

Abstract. Bovine casein gene cluster belongs to the best studied regions of the bovine genome. However, molecular basis of the regulation of casein gene expression is still of great interest for the advancement of milk production. Identification of crucial regulatory regions governing casein gene expression would provide valuable information for marker assisted selection in dairy cattle. In our study we performed comparative analysis of the bovine beta- and kappa casein gene promoter sequences with the regulatory sequences from some other species. In addition, we used homologous mammary gland derived cell culture and luciferase reporter gene system to confirm the functionality of the proximal beta and kappa casein promoters. The longer kappa casein promoter (2064 bp) showed the highest expression level, followed by the short kappa casein promoter (925 bp) and beta casein promoter (1692 bp). Here we demonstrate the suitability of the bovine mammary gland derived cell line BME UV1 for transient gene expression under transcriptional control of the bovine casein gene promoters and compare functionality of different fragments of bovine beta- and kappa casein gene promoters using homologous in vitro system.