B4GALT1和Wntless合作阻止LRP5/6从Golgi转移到细胞表面的转移
Xinyang Li1, Yue Hua2, Jiahui Wang1
1Department of Biochemistry and Molecular Biology, Key Laboratory of Metabolism and Molecular Medicine, Ministry of Education, School of Basic Medical Sciences, Fudan University, Shanghai, PR China.
The Journal of cell biology
|November 3, 2025
概括
戈尔吉酶B4GALT1保留了戈尔吉细胞中的LRP5/6共受体,减少了它们在细胞表面的存在. Wnt分泌活动抵消了这种保留,影响了LRP5/6细胞表面呈现.
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:
- 低密度脂蛋白受体相关蛋白5/6 (LRP5/6) 是Wnt蛋白的关键共受体,介导WNT/β-catenin信号传递.
- 翻译后,LRP5/6通过内质网膜和戈尔吉装置被运送到细胞表面.
研究的目的:
- 调查戈尔吉居民β-1,4-银酸转移酶 (B4GALT1) 在LRP5/6.6的贩运和细胞表面呈现中的作用.
- 阐明B4GALT1,LRP5/6和Wnt分泌在调节WNT/β-catenin信号传递中的相互作用.
主要方法:
- 同免疫沉测试以确定蛋白质相互作用.
- 细胞表面蛋白质生物化和西式涂抹以量化细胞表面LRP5/6水平.
- 用LGK974进行治疗以破坏Wnt/Wntless复合体.
主要成果:
- B4GALT1直接与LRP5 / 6相互作用,导致它们在戈尔吉装置中被保留并减少细胞表面表达.
- B4GALT1也结合Wntless,一个Wnt载体,但这种相互作用调节LRP5/6戈尔吉保留,而不是影响Wnt分泌.
- 通过占用Wntless,Wnt分泌对抗B4GALT1介导的LRP5/6戈尔吉保留.
- 使用LGK974抑制Wnt/Wntless复合物增强LRP5/6戈尔吉保留,减少它们转移到细胞表面.
结论:
- LRP5/6的细胞表面呈现是由戈尔吉定居酶B4GALT1.1动态调节的.
- Wnt分泌活动在抵消B4GALT1介导的LRP5/6保留方面发挥着重要作用,从而影响LRP5/6在细胞表面的可用性.
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