Palmer D G, Dorling P R, Howell J M
School of Veterinary Studies, Murdoch University, Perth, Western Australia.
Neuromuscul Disord. 1994 Jan;4(1):39-48. doi: 10.1016/0960-8966(94)90046-9.
The molecular defect in Shorthorn cattle affected with glycogenosis type II was studied. Polyclonal and monoclonal antibodies specific for bovine skeletal muscle acid alpha-glucosidase were raised and used to study the molecular and biochemical defect in seven affected animals. Cultured normal bovine fibroblasts pulsed and chased with [3H] leucine produced a 130 kDa precursor form of acid alpha-glucosidase which was processed via several 100 kDa intermediate forms to the 65 kDa mature form within 26 h. Fibroblasts from affected animals were labelled in vitro and were shown to produce a cross-reactive protein which was identified as the precursor form of the enzyme. The mature form of the enzyme was not found. The precursor form of the enzyme was demonstrated in Western blots of muscle tissue extracts from affected animals. Glycogenosis type II in Shorthorn and Brahman cattle must be caused by a different, independent maturation, since Brahman cattle lack the cross-reactive protein for acid alpha-glucosidase.
对患II型糖原贮积病的短角牛的分子缺陷进行了研究。制备了针对牛骨骼肌酸性α-葡萄糖苷酶的多克隆和单克隆抗体，并用于研究7只患病动物的分子和生化缺陷。用[3H]亮氨酸脉冲追踪培养的正常牛成纤维细胞，产生了一种130 kDa的酸性α-葡萄糖苷酶前体形式，该前体在26小时内通过几种100 kDa的中间形式加工成65 kDa的成熟形式。患病动物的成纤维细胞在体外进行标记，结果显示产生了一种交叉反应蛋白，该蛋白被鉴定为该酶的前体形式。未发现该酶的成熟形式。在患病动物肌肉组织提取物的Western印迹中证实了该酶的前体形式。短角牛和婆罗门牛的II型糖原贮积病一定是由不同的、独立的成熟过程引起的，因为婆罗门牛缺乏酸性α-葡萄糖苷酶的交叉反应蛋白。
