%0 Journal Article
%T Variations in the Regulatory Region of Alpha S1-Casein Milk Protein Gene among Tropically Adapted Indian Native (Bos Indicus) Cattle
%A Amit Kishore
%A Manishi Mukesh
%A Ranbir C. Sobti
%A Bishnu P. Mishra
%A Monika Sodhi
%J ISRN Biotechnology
%D 2013
%R 10.5402/2013/926025
%X Regulatory region of milk protein alpha S1-casein (¦ÁS1-CN) gene was sequenced, characterized, and analyzed to detect variations among 13 Indian cattle (Bos indicus) breeds. Comparative analysis of 1,587£¿bp region comprising promoter (1,418£¿bp), exon-I (53£¿bp), and partial intron-I (116£¿bp) revealed 35 nucleotide substitutions (32 within promoter region, 1 in exon-I, and 2 in partial intron-I region) and 4 Indels. Within promoter, 15 variations at positions £¿1399 (A£¿>£¿G), £¿1288 (G£¿>£¿A), £¿1259 (T£¿>£¿C), £¿1158 (T£¿>£¿C), £¿1016 (A£¿>£¿T), £¿941 (T£¿>£¿G), £¿778 (C£¿>£¿T), £¿610 (G£¿>£¿A), £¿536 (A£¿>£¿G), £¿521 (A£¿>£¿G), £¿330 (A£¿>£¿C), £¿214 (A£¿>£¿G), £¿205 (A£¿>£¿T), £¿206 (C£¿>£¿A), and £¿175 (A£¿>£¿G) were located within the potential transcription factor binding sites (TFBSs), namely, NF-¦ÊE1/c-Myc, GATA-1, GATA-1/NF-E, Oct-1/POU3F2, MEF-2/YY1, GATA-1, AP-1, POU1F1a/GR, TMF, GAL4, YY1/Oct-1, HNF-1, GRalpha/AR, GRalpha/AR, and AP-1, respectively. Seventy-four percent (26/35) of the observed SNPs were novel to Indian cattle and 11 of these novel SNPs were located within one or more TFBSs. Collectively, these might influence the binding affinity towards their respective nuclear TFs thus modulating the level of transcripts in milk and affecting overall protein composition. The study provides information on several distinct variations across indicine and taurine ¦ÁS1-CN regulatory domains. 1. Introduction Bovine caseins are distinguished into four protein fractions, namely, alpha S1-casein, alpha S2-casein, beta-casein, and kappa-casein encoded by genes: ¦ÁS1-CN, ¦ÁS2-CN, ¦Â-CN, and ¦Ê-CN, respectively [1]. Alpha S1-casein represents the major protein fraction (31%) among the bovine milk proteins (caseins and whey) and constitutes up to 40% of total casein [1]. It is a calcium sensitive and highly phosphorylated protein. It has an important role in the capacity of milk to transport calcium phosphate and is organized at 5¡ä-terminus of casein cluster located on bovine chromosome 6 (BTA6). Till now, 9 variants (A-I) have been reported in the coding region of ¦ÁS1-CN. Amongst these, B and C, differing in amino acid substitution (Glu/Gly) at position 192 of the mature protein, are the most common. The variant C has been reported to be common in zebu breeds, while other rare variants like A, D, and F have only been reported in European cattle [2]. These variants are well characterized and their associations with quantitative effects on milk performance/production parameters have been widely reported [3, 4]. The results on association studies involving only coding region variants are not always
%U http://www.hindawi.com/journals/isrn.biotechnology/2013/926025/