Majumder S, Brown K, Qiu F H, Besmer P
Laboratory of Molecular Oncology, Memorial Sloan-Kettering Cancer Center, New York, New York.
Mol Cell Biol. 1988 Nov;8(11):4896-903. doi: 10.1128/mcb.8.11.4896-4903.1988.
The proto-oncogene c-kit encodes a transmembrane kinase which is related to the receptors for colony-stimulating factor type 1 and platelet-derived growth factor, as well as to the immunoglobulin superfamily. Antibodies specific for the kinase domain of the P80 gag-kit protein of the Hardy-Zuckerman 4 feline sarcoma virus were prepared. These kit-specific antibodies were used to identify and characterize the c-kit protein in cat brain tissue. The c-kit protein product displays an autophosphorylating activity in immune complex kinase assays, and, in turn, this activity was used to identify the c-kit protein in different tissues. In cat brain, a single 145-kilodalton (kDa) glycoprotein was detected. Its N-linked carbohydrates were found to be sensitive to digestion with the endoglycosidases (neuraminidase, endoglycosidase F, and endoglycosidase H), indicating hybrid and/or complex and high-mannose structures. A partial purification of the c-kit protein was achieved by wheat germ agglutinin affinity chromatography, and the autophosphorylating activity of the partially purified c-kit protein was characterized and found to be specific for tyrosine. The kit antibodies cross-react with the murine c-kit protein product, and variant c-kit proteins in different mouse tissues were identified, with sizes of about 145 kDa (brain), 160 kDa (spleen), and 150 kDa (testis).
原癌基因c-kit编码一种跨膜激酶，它与1型集落刺激因子和血小板衍生生长因子的受体相关，也与免疫球蛋白超家族相关。制备了针对哈代-祖克曼4型猫肉瘤病毒P80 gag-kit蛋白激酶结构域的特异性抗体。这些kit特异性抗体用于鉴定和表征猫脑组织中的c-kit蛋白。在免疫复合物激酶分析中，c-kit蛋白产物表现出自身磷酸化活性，反过来，这种活性被用于鉴定不同组织中的c-kit蛋白。在猫脑中，检测到一种单一的145千道尔顿（kDa）糖蛋白。发现其N-连接碳水化合物对内切糖苷酶（神经氨酸酶、内切糖苷酶F和内切糖苷酶H）的消化敏感，表明具有杂合和/或复杂及高甘露糖结构。通过麦胚凝集素亲和层析实现了c-kit蛋白的部分纯化，并对部分纯化的c-kit蛋白的自身磷酸化活性进行了表征，发现其对酪氨酸具有特异性。kit抗体与小鼠c-kit蛋白产物发生交叉反应，并鉴定了不同小鼠组织中的变异c-kit蛋白，其大小约为145 kDa（脑）、160 kDa（脾）和150 kDa（睾丸）。
