菌体编码了在共生互生中保护所需的因素
Kerry M Oliver1, Patrick H Degnan, Martha S Hunter
1Department of Entomology, University of Georgia, Athens, GA 30602, USA. kmoliver@uga.edu
Science (New York, N.Y.)
|August 22, 2009
概括
菌体,感染细菌的病毒,对于保护性共生体Hamiltonella defensa来说至关重要,以捍卫虫对抗寄生虫. 这些细菌的菌体损失损害了虫的防御.
科学领域:
- 微生物学 微生物学
- 昆虫与微生物的相互作用
- 细菌生物学的细菌生物.
背景情况:
- 菌体经常携带致病性细菌的毒性因子.
- 菌体在共生细菌中的作用,特别是在赋予宿主益处方面,人们对其理解较少.
- 汉密尔托尼拉防御是一种可遗传的细菌共生体,可以保护虫 (Acyrthosiphon pisum) 免受寄生虫黄蜂 (Aphidius ervi) 的伤害.
研究的目的:
- 研究菌体在Hamiltonella defensa赋予其虫宿主的保护性表型中的作用.
- 为了确定细菌是否对虫对寄生虫攻击的防御至关重要.
主要方法:
- 控制的基因背景实验,使用感染了Hamiltonella defensa的虫克隆线.
- 监测实验室中共生动物种群中的菌体损失.
- 评估虫在菌体损失后对寄生虫攻击的易感性.
主要成果:
- 在Hamiltonella defensa中,需要一种编码毒素的菌体来保护对寄生虫的保护性表型.
- 在实验室维护的虫线中,反复观察到菌体损失.
- 菌体的丧失导致了虫对寄生虫攻击的易感性增加.
结论:
- 菌体可以作为生态重要特征的载体,例如对寄生虫的防御.
- 像细菌菌体这样的移动遗传元素可以为细菌共生体提供好处,这些共生体可以延伸到它们的动物宿主.
- 菌体在昆虫宿主中调解共生体介导的防御中发挥着关键作用.
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