摇蛇毒中与年龄相关的变化的遗传调节架构和表观基因组基础
Michael P Hogan1, Matthew L Holding1,2, Gunnar S Nystrom1
1Department of Biological Science, Florida State University, Tallahassee, FL 32306.
概括
蛇发育过程中的基因表达变化是由表观基因组转变驱动的. 这些转录因子的变化调节了毒素的组成,为适应性生命史进化提供了洞察力.
科学领域:
- 进化生物学是进化的生物学.
- 基因组学就是基因组学.
- 分子生物学分子生物学
背景情况:
- 生物体的发育变化可以由与年龄和大小相关的生态压力形成.
- 基因表达的编程变化驱动了许多适应性表型变化,但根本的分子机制尚未完全理解.
- 毒蛇,如东方钻石背蛇 (Crotalus adamanteus),在饮食和毒液成分上表现出年龄相关的变化,使它们成为研究定时基因表达的有价值模型.
研究的目的:
- 确定控制C. adamanteus.中毒本体发生的分子机制和基因调节网络.
- 研究蛇发育过程中表观基因组变化和基因表达之间的关系.
- 了解转录因子在适应性生命史特征进化中的作用.
主要方法:
- 为C. adamanteus.生成了染色体水平的基因组组合.
- 综合基因组,转录基因 (基因表达) 和表观基因组 (染色质可访问性,基因组修饰) 数据来自毒液腺.
- 确定了影响毒腺基因表达的 cis 调节元素和 trans 调节因素.
主要成果:
- 发现了本体遗传基因表达变化和毒素基因内及周围的表观基因修饰之间的显著相关性.
- 确定了37个候选转录因子 (TFs) 参与毒素本体发生,其中大多数在成年人中被上调调节.
- 发现与成长,转录激活和生物学定时相关的TFs的表达增加在成年人中驱动毒素组成的变化,伴随着表观基因组的改变.
- 观察到基因表达的激活和抑制,这有助于幼蛇和成年蛇之间的毒液变化.
结论:
- 毒素基因附近的表观基因变化与毒素成分的发育转变密切相关.
- 调节生长,激活和时间的转录因子在毒素发育过程中起着关键作用.
- 基因激活和抑制的复杂相互作用凸显了基因调节在适应性特征中的可变性.
- 这项研究为了解不同物种中依赖年龄的生命史特征的基因调节网络演变提供了一个框架.
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