在Bacillus thuringiensis哭泣基因中的调控多样性揭示了活体中毒素表达的灵活进化策略
Isabel Gómez1, Blanca I Garcia-Gómez1, Nathaly A do Nascimento1
1Departamento de Microbiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, Mexico.
PLoS pathogens
|March 4, 2026
概括
昆虫杀伤性Bacillus thuringiensis (Bt) 杀虫剂Cry蛋白显示出多种不同的上游调节序列. 保存的动机与宿主范围相关,表明监管进化推动了Bt多样化和生态成功.
科学领域:
- 微生物学 微生物学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 硫杆菌 (Bt) 产生各种杀虫剂Cry蛋白,对其作为病原体的有效性至关重要.
- 三域Cry蛋白家族虽然很可能是从共同的祖先进化而来的,但在上游调节区域表现出显著的变异性.
研究的目的:
- 为了研究Bacillus thuringiensis (Bt) Cry蛋白家族内上游调节序列的分歧.
- 确定保存的调节元素及其与昆虫特异性和宿主范围的相关性.
主要方法:
- 利用多重期望最大化用于动机诱导 (MEME) 和寻找个体动机事件 (FIMO) 进行动机发现.
- 分析了正规的 -10 和 -35 促销器动机和Shine-Dalgarno (SD) 序列.
- 在异质上游区域下克隆了cry1Ab和cry4Ba基因,并在不同的Bt菌株中表达它们,用于体外和体内生物评估.
主要成果:
- 上游调节序列在整个Cry家族中并不普遍保留.
- 具有类似昆虫特异性的基因子集共享保存的模式架构,表明调节进化和宿主范围之间的联系.
- 不同的上游序列可以导致类似的表达模式,表明Bt.中的多个调节策略.
结论:
- 蛋白表达受促进体身份和Bt菌株背景的影响.
- 上游调节序列在Bacillus thuringiensis的多样化和生态适应中发挥着重要作用.
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