伊波梅素F与Sec61α结合以抑制蛋白转位
Guanghui Zong1, Zhijian Hu, Sarah O'Keefe2
1Department of Chemistry and Biochemistry , University of Maryland , College Park , Maryland 20742 , United States.
Journal of the American Chemical Society
|May 7, 2019
概括
植物性细胞毒素ipomoeassin F直接与Sec61α (蛋白质运输蛋白Sec61亚单元α异型1) 结合,从而抑制蛋白质转位和分泌. 这一发现为针对Sec61α的癌症药物发现开辟了新的途径.
科学领域:
- 生物化学
- 分子生物学
- 药理学
背景情况:
- 伊波梅素F是一种强大的天然细胞毒素,具有尚未探索的生物特性.
- 之前的工作确定了ipomoeassin F的总合成和药用化学成分.
研究的目的:
- 在活细胞中识别ipomoeassin F的直接分子标.
- 为了研究ipomoeassin F对其目标的功能后果.
- 作为一种潜在的治疗药物.
主要方法:
- 化学蛋白质组使用生物化伊波梅素F类似物.
- 关联拉下测试和西方抹去.
- 在体外蛋白转位测试.
- 在体内蛋白质分泌量测试.
- 在Sec61α的位点定向突变.
主要成果:
- 鉴定出Sec61转位素的孔形成子单元Sec61α (蛋白质运输蛋白Sec61亚单元α异型1),是ipomoeassin F的直接结合伙伴.
- 伊波梅素F与Sec61α之间的相互作用是特定的,强烈的和可逆的.
- 结合ipomoeassin F可以选择性地抑制活细胞中的蛋白质转位和蛋白质分泌.
- 在Sec61α中的特定突变赋予了对ipomoeassin F的耐药性,确认它是主要的分子标.
结论:
- 伊波梅素F是第一个被发现能够向Sec61α的植物性碳水化合物分子.
- 这种天然产品为研究Sec61α功能提供了一个新的化学探针.
- 伊波梅素F代表着针对癌症和其他涉及蛋白质转位缺陷的疾病的药物发现的潜在治疗头.
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