Shao H, Lou L, Pandey A, Pasquale E B, Dixit V M
Department of Pathology, University of Michigan Medical School, Ann Arbor 48109.
J Biol Chem. 1994 Oct 28;269(43):26606-9.
We have isolated a murine cDNA encoding a ligand for the Cek5 receptor protein-tyrosine kinase (RPTK), a member of the Eph/Eck RPTK subfamily. Sequence analysis predicts an open reading frame of 345 amino acids with a predicted molecular mass of 38 kDa. Metabolic labeling and immunoprecipitation of cells transfected with a cDNA encoding the Cek5 ligand revealed the mature protein to have an apparent molecular mass of 45 kDa. The extracellular domain of the Cek5 ligand shows a 27% sequence identity at the protein level to B61, a ligand for the related Eck RPTK (Bartley, T. D., et al. (1994) Nature 368, 558-560). Consistent with the presence of a transmembrane domain, flow cytometry analysis revealed the Cek5 ligand to be expressed on the cell surface. The expressed Cek5 ligand is functionally active as it induces autophosphorylation of the Cek5 RPTK.
我们分离出了一种小鼠cDNA，它编码Cek5受体蛋白酪氨酸激酶（RPTK）的配体，Cek5属于Eph/Eck RPTK亚家族。序列分析预测其开放阅读框有345个氨基酸，预测分子量为38 kDa。用编码Cek5配体的cDNA转染细胞后进行代谢标记和免疫沉淀，结果显示成熟蛋白的表观分子量为45 kDa。Cek5配体的胞外结构域在蛋白质水平上与B61有27%的序列同一性，B61是相关的Eck RPTK的配体（Bartley, T. D.,等人（1994年）《自然》368, 558 - 560）。与存在跨膜结构域一致，流式细胞术分析显示Cek5配体在细胞表面表达。所表达的Cek5配体具有功能活性，因为它能诱导Cek5 RPTK的自身磷酸化。
