Liu J, Qian L D, Huo J L, Bi B L, Li D L, Wang S F, Chen T, Li L J, Mao H M, Miao Y W
Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming, Yunnan, China.
Department of Husbandry and Veterinary, Yunnan Vocational and Technical College of Agriculture, Kunming, Yunnan, China.
Genet Mol Res. 2015 Mar 27;14(1):2290-301. doi: 10.4238/2015.March.27.14.
Parathyroid hormone-related protein (PTHrP) is involved in the deposition of milk calcium in mammal lactation, but its role in buffalo is unclear. In this study, the full-length coding sequence of the water buffalo PTHrP gene was first isolated using reverse transcription-polymerase chain reaction. The protein was then subjected to molecular characterization using bioinformatic methods, and the tissue expression pattern was further assayed by semi-quantitative reverse-transcription polymerase chain reaction. The water buffalo PTHrP gene contains an open reading frame of 534 base pairs encoding a polypeptide of 177 amino acid residues, a theoretical molecular weight of 20.32 kDa, and an isoelectric point of 10.00. In addition, water buffalo PTHrP was predicted to contain a signal peptide, a typical hydrophobic region with no hydrophobic transmembrane regions, and to exert its function in the cell nucleus. A conserved domain of parathyroid superfamily from amino acids 34-114 was observed in the polypeptide. Sequence comparison and the phylogenetic analysis showed that the sequence of the water buffalo PTHrP protein shared high homology with that of other mammals, particularly cattle and goat. Among the 16 tissues examined, the PTHrP gene was only expressed in adipose tissue, placenta, uterine wall, hypophysis, and mammary gland tissue, but gene expression levels were higher in the uterus wall and adipose tissue. The results of this study suggest that the PTHrP gene plays an important role in the deposition of milk calcium of water buffalo.
甲状旁腺激素相关蛋白（PTHrP）参与哺乳动物泌乳过程中乳钙的沉积，但其在水牛中的作用尚不清楚。在本研究中，首先利用逆转录-聚合酶链反应分离出了水牛PTHrP基因的全长编码序列。然后采用生物信息学方法对该蛋白进行分子特征分析，并通过半定量逆转录-聚合酶链反应进一步检测其组织表达模式。水牛PTHrP基因包含一个534个碱基对的开放阅读框，编码一个由177个氨基酸残基组成的多肽，理论分子量为20.32 kDa，等电点为10.00。此外，预测水牛PTHrP含有一个信号肽，一个典型的疏水区域且无疏水跨膜区域，并在细胞核中发挥功能。在该多肽中观察到了甲状旁腺超家族从第34至114位氨基酸的保守结构域。序列比较和系统发育分析表明，水牛PTHrP蛋白的序列与其他哺乳动物，特别是牛和山羊的序列具有高度同源性。在所检测的16种组织中，PTHrP基因仅在脂肪组织、胎盘、子宫壁、垂体和乳腺组织中表达，但在子宫壁和脂肪组织中的基因表达水平较高。本研究结果表明，PTHrP基因在水牛乳钙沉积中起重要作用。
