CDNA Cloning And Tissue Expression Of TNNC1、TNNC2and TNNT3in Tianfu Goat

Troponins(TNs), belong to a member of multigene family of Ca2+binding proteins, plays a critical role in skeletal muscle contraction and improving meat quality traits of livestock and poultry. The troponins gene has been identified in many mammals, but very little known about goat. Here, we cloned TNNC1、TNNC2and TNNT3gene in Tianfu goat for the first time and analyzed its tissue expression. We submitted them to NCBI and three Genbank ID were obtained (TNNC1: HQ640744; TNNC2:HQ640745;TNNT3:JF816256), this was the first report of gene sequence of TNNC1、TNNC2and TNNT3in goat. Researches have indicated that troponins was associated with meat tenderness, therefore NNC1、TNNC2and TNNT3can be deemed to important candidate genes for meat quality traits.Results indicated that TNNC1contains483bp CDS and encodes161amino acids, and it was selectively expressed in the muscular tissues of goat. Its nucleotide sequence was high similar in various animal ranged from97.94%(cow) to83.33%(African clawed frog), and the identity of encoded amino acids varied from100%(cow) to92.55%(smelt). Fluorescence quantitative PCR analyses revealed that the TNNC1gene selectively expressed in the muscular tissues of goat, it expressed in cardiac tissue and slow skeletal muscle (soleus), which was significantly higher than that of fast skeletal muscle and other internal organs (P<0.01). In addition, the expression of TNNC1to reduce with increase gradually of age, moreover, the highest when the goat was at the age of three. The amino acid residue of Ca2+binding site II was identical in mammals、aves and fish.Results indicated that TNNC2contains483bp CDS and encodes160amino acids, and it was selectively expressed in the muscular tissues of goat. In summary, the expression of TNNC2in muscle tissues were higher than internal organs, when the goat was six-month-old, the highest expression was detected in longissimus, which was with eyes closed are longer than that of cardiac muscle and internal organs (P<0.01), and the expression of TNNC1reduce with the rise of the age.Its nucleotide sequence was high similar with93.38%(sheep) and90.48%(alpaca), and the identity of encoded amino acids which was varied from100%(Sheep) to70.81%(Atlantic salmon) in animal. We found that the Ala113and leu132was distributed very law in mammals. The amino acid residue of Ca2+binding sites Ⅱ was identical in mammals, Aves and amphibian.Results indicated that TNNT3contains801bp CDS and encodes267amino acids. Homological analysis indicated that the nucleotide sequence was similar with95.01%(cow) to81.20%(mus), and the identity of encoded amino acids which was varied from95.49%(cow) to87.13%(mus) in mammals.