Zhu A X, Zhao Y, Flier J S
Department of Medicine, Beth Israel Hospital/Harvard Medical School, Boston, MA 02215.
Biochem Biophys Res Commun. 1994 Dec 30;205(3):1875-82. doi: 10.1006/bbrc.1994.2889.
Two distinct cDNAs encoding small GTP-binding proteins were isolated from a human fetal skeletal muscle cDNA library. Nucleotide sequence analysis revealed that one clone encodes a protein of 218 amino acids, which shares highest amino acid identities (over 90%) with the members of YPT3 GTP-binding proteins subfamily and was termed H-YPT3; and the second clone encodes a protein of 201 amino acids, which exhibits strongest homology to rab1A, rab1B, and YPT1 at its N-terminus but diverges notably from these rab family members at the C-terminus. The second cDNA may represents a novel member of the small GTP-binding protein family and was designated H-ray. Northern blot analysis shows that both genes are ubiquitously expressed. Using a bacterial expression vector, each clone was overexpressed in Escherichia coli. The two bacterially produced proteins possess GTP-binding activity.
从人胎儿骨骼肌cDNA文库中分离出两个编码小GTP结合蛋白的不同cDNA。核苷酸序列分析显示，一个克隆编码一个由218个氨基酸组成的蛋白质，该蛋白质与YPT3 GTP结合蛋白亚家族成员具有最高的氨基酸同一性（超过90%），被命名为H-YPT3；第二个克隆编码一个由201个氨基酸组成的蛋白质，其N端与rab1A、rab1B和YPT1具有最强的同源性，但在C端与这些rab家族成员有明显差异。第二个cDNA可能代表小GTP结合蛋白家族的一个新成员，被命名为H-ray。Northern印迹分析表明这两个基因均普遍表达。使用细菌表达载体，每个克隆在大肠杆菌中过表达。两种细菌产生的蛋白质都具有GTP结合活性。
