Vestri R, Crema C, Marinucci M, Giordano P C, Bernini L F
Biochim Biophys Acta. 1980 Oct 21;625(2):328-36. doi: 10.1016/0005-2795(80)90297-4.
Only one type of alpha chain has been described so far in the hemoglobins of adult domestic sheep. A variant (Hb D) of the alpha chain, characterized by a substitution glycine leads to aspartic acid at position 15, has been described in Yugoslavian sheep. In this paper we report the identification of a second alpha chain (alpha 2), observed in several sheep when the globin was analyzed by CM-cellulose chromatography or the total hemolysate submitted to isoelectric focusing. The ratio of this chain to the usual one (alpha 1) in the globin of different animals is equal to either 1 : 2 or 1 : 4. The structural difference between alpha 1 and alpha 2 chains consists in the replacement of a leucine residue by an histidine in the position 113 or 114 of the polypeptide chain. Preliminary data on the frequency of the alpha 2 chain in eight domestic breeds indicate that this chain is fairly common, being present in 15 out of 40 animals examined. The results of breeding experiments between sheep of an appropriate alpha chain phenotype suggest the possibility of a duplication of the hemoglobin alpha locus in the Ovinae.
到目前为止，在成年家养绵羊的血红蛋白中仅发现了一种α链。在南斯拉夫绵羊中发现了α链的一种变体（Hb D），其特征是在第15位由甘氨酸替换为天冬氨酸。在本文中，我们报告了通过CM - 纤维素色谱分析球蛋白或对总溶血产物进行等电聚焦时，在几只绵羊中观察到的第二条α链（α2）的鉴定。不同动物球蛋白中该链与常见的α1链的比例为1 : 2或1 : 4。α1链和α2链的结构差异在于多肽链第113或114位的一个亮氨酸残基被组氨酸取代。对八个家养品种中α2链频率的初步数据表明，该链相当常见，在所检测的40只动物中有15只存在。对具有合适α链表型的绵羊进行育种实验的结果表明，在羊亚科中存在血红蛋白α基因座重复的可能性。
