在B淋巴细胞中,ras蛋白与表面免疫球蛋白的共同封闭
L Graziadei1, K Riabowol, D Bar-Sagi
1Cold Spring Harbor Laboratory, New York 11724.
Nature
|September 27, 1990
概括
p21ras蛋白与B淋巴细胞中的表面免疫球蛋白受体共同结,表明它们在B细胞激活信号传递中的作用. 这种定向的膜迁移被代谢和细胞骨破坏者抑制.
科学领域:
- 细胞和分子生物学 细胞和分子生物学
- 免疫学 免疫学 免疫学
- 信号传输 信号传输
背景情况:
- 细胞ras基因对参与生长信号的p21ras蛋白进行编码.
- 体诱导的受体运动是细胞生长和分化信号转导的关键.
- B 淋巴细胞的激活涉及表面免疫球蛋白受体封闭.
研究的目的:
- 研究p21ras蛋白在B淋巴细胞激活中的作用和局部化.
- 为了确定p21ras蛋白是否参与由表面免疫球蛋白限制启动的信号传导途径.
主要方法:
- 免疫光显微镜可视化p21ras和表面免疫球蛋白的分布.
- 在免疫球蛋白和康卡纳瓦林A受体上限期间对p21ras再分配的分析.
- 使用代谢抑制剂和细胞骨破坏剂 (胆素,细胞素D) 来评估p21ras运动.
主要成果:
- 在小鼠骨B淋巴细胞中,p21ras配合表面免疫球蛋白分子.
- 在免疫球蛋白上限的早期补丁阶段,p21ras重新分配发生.
- 代谢抑制剂和细胞骨破坏剂可以抑制p21ras封闭.
- 在康卡纳瓦林A受体封闭期间,没有观察到p21ras分布的变化.
- 基α子单元的分布不受表面免疫球蛋白上限的影响.
结论:
- p21ras蛋白在血上呈现有针对性的迁移.
- p21ras蛋白可能是B淋巴细胞表面免疫球蛋白封闭启动的信号通路的组成部分.
- 这些发现为B细胞激活和生长信号的机制提供了洞察力.
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