Polymorphisms of the kappa casein (CSN3) gene and inference of its variants in water buffalo (Bubalus bubalis)
Polymorphisms of the kappa casein (CSN3) gene and inference of its variants in water buffalo (Bubalus bubalis)
复制标题
水牛 (Bubalus bubalis) 中 kappa 酪蛋白 (CSN3) 基因的多态性及其变异的推断。
DOI：
10.5194/aab-62-585-2019
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发表时间：
2019-12-05
影响因子：
1.8
通讯作者：
Miao, Yongwang
中科院分区：
文献类型：
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作者：
Fan, Xinyang;Zhang, Zifang;Miao, Yongwang
Kappa酪蛋白在形成稳定的酪蛋白胶束中起着关键作用，并对凝乳性能有关键影响。然而，目前对水牛CSN3基因多态性的了解还不够充分。本研究采用聚合酶链式反应产物直接测序法检测了水牛CSN3基因全编码序列(CDS)的多态性。河水牛和沼泽水牛CSN3的CDS序列长度相同，含有573个核苷酸的开放阅读框，编码190个氨基酸残基的多肽。在两种类型的水牛中共检测到8个单核苷酸多态(SNPs)。其中c.86C>；T、c.252G>；C、c.445G>；A、c.467C>；T和c.516A>；C互不同义，导致kappa酪蛋白(kappa-CN)中分别存在p.Pro8Leu、p.Lys63Asn、p.Va1128Ile、p.Thr135Ile和p.Glu151Asp替换。P.Thr135Ile的替换可能对水牛kappa-CN的功能产生重要影响。根据在水牛中发现的SNPs，定义了11个单倍型，据此推断出水牛kappa-CN的7个蛋白变种和4个同义变种，分别称为变种A、B、B-1、C、C-1、C-2、D、E、F、F-1和G。此外，还鉴定了水牛和牛属Kappa-CN的14个氨基酸差异位点，其中3个位于糖基化位点(80S、96T、141S)，4个位于磷酸化位点(19S、80S、96T、141S)。据推测，它们可能导致了水牛和牛属之间kappa-CN的理化性质的差异。本研究为探索CSN3基因变异与水牛哺乳性状的相关性奠定了基础。
Kappa casein plays a crucial role in the formation of stable casein micelles and has a key influence on milk-clotting properties. However, current understanding of buffalo CSN3 gene polymorphisms is not sufficient. In this study, the polymorphisms in the complete coding sequence (CDS) of the buffalo CSN3 were detected using PCR product direct sequencing. The CDS of CSN3 for river and swamp buffalo was the same in length, which contained an open reading frame of 573 nucleotides encoding a peptide containing 190 amino acid residues. A total of eight single nucleotide polymorphisms (SNPs) was identified in two types of buffalo. Among them, c.86C>T, c.252G>C, c.445G>A, c.467C>T and c.516A>C were non-synonymous, which leads to p.Pro8Leu, p.Lys63Asn, p.Va1128Ile, p.Thr135Ile and p.Glu151Asp substitutions in buffalo kappa casein (kappa-CN), respectively. The substitution of p.Thr135Ile may exert a vital effect on the function of buffalo kappa-CN. Eleven haplotypes were defined based on the SNPs found in buffalo, and accordingly, seven protein variants and four synonymous variants of buffalo kappa-CN were inferred, called variants A, B, B-1, C, C-1, C-2, D, E, F, F-1 and G. The variants observed in water buffalo did not exist in the Bos genus. In addition, 14 amino acid differential sites of kappa-CN between buffalo and the Bos genus were identified, of which 3 were located at glycosylation sites (80S, 96T, 141S) and 4 at phosphorylation sites (19S, 80S, 96T, 141S). It is speculated that they may lead to differences in the physicochemical properties of kappa-CN between buffalo and the Bos genus. This study will lay a foundation for exploring the association between the variation in the CSN3 gene and the lactation traits of buffalo.