一种新型的维特龙菌素受体整合素 (alpha v beta x) 是致癌细胞独特的粘合性质的原因
D A Cheresh1, J W Smith, H M Cooper
1Department of Immunology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Cell
|April 7, 1989
概括
癌细胞利用一种独特的整体因子受体来进行维特龙菌素和纤维龙菌素的粘附,与黑色素瘤和内皮细胞中发现的维特龙菌素受体不同. 这种新型的整合蛋白包括一个alpha v子单元和一个新的β x子单元,突出了细胞矩阵相互作用中的多种整合蛋白功能.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 整合素是关键的细胞表面受体,调解细胞矩阵相互作用.
- 不同的细胞类型表现出不同的整合素表达特征,影响粘附.
- 已知维特罗涅丁受体 (alpha v beta 3) 可以结合多个矩阵蛋白.
研究的目的:
- 描述涉及癌细胞粘附的新型整合素.
- 为了确定癌细胞整体的子单元组成.
- 阐明这个整合素在矩阵识别中的功能作用.
主要方法:
- 细胞粘附测试使用维特罗涅丁,纤维素和·维勒布兰德因子.
- 针对整合素子单元的抗体阻断实验.
- 北方斑分析检测特定的整合素亚单元mRNAs.
主要成果:
- 癌细胞通过一种新型的整体蛋白粘附于维特龙菌素,与表达alpha v beta 3的黑色素瘤和内皮细胞不同.
- 癌瘤整合蛋白与αv子单元共享,但具有不同的βx子单元.
- 这种新型的整合素调节了对维特龙菌素和纤维龙菌素的粘附.
结论:
- 癌细胞使用一种独特的整合素 (alpha v beta x) 进行特定的矩阵粘附.
- 同类的α子单元可以与不同的β子单元配对,以创建功能多样化的整体.
- 集成蛋白结构决定了细胞外矩阵组件的差异识别.
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