Cloning, characterization and identification of polymorphism in TCR Zeta Gene in Deoni cattle

The cDNA encoding, T-cell receptor zeta (TCR Ć CD247) molecule of Deoni cattle (Bos indicus), was isolated, cloned and sequenced in the present study. The CD247 cDNA comprised 1078 nucleotides including a 30 nucleotide 5¹-untranslated region (UTR), 495 nucleotide single open reading frame (ORF) and 553 nucleotide 3¹-UTR. Deduced amino acid of cattle CD247 sequence was two residues shorter than the corresponding sheep sequences. However, ruminant-specific insertions and substitutions in transmembrane (TM) and intra-cytoplasmic (IC) domain were present in cattle. Immunoreceptor tyrosinebased activation motifs (ITAMs), the important motifs for TCR signalling, were totally conserved among ruminants including cattle. The 3’-UTR region of the cattle CD247 was highly homologous to the corresponding region in the buffalo sequence and showed lack of polymorphism after polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis using Hae III and Mse I restriction enzymes in cattle population. Phylogenetically, cattle sequence was closer to buffalo sequence under theruminant's lineage. The conserved nature of this gene ensures TCR integrity whichis vital for induction of optimal and efficient immune response.