古代鱼类血统揭示了脊椎动物早期进化过程中的类似收费的受体多样化
Kara B Carlson1,2, Cameron Nguyen3, Dustin J Wcisel1
1Department of Molecular Biomedical Sciences, North Carolina State University, Raleigh, NC, USA.
Immunogenetics
|August 9, 2023
概括
脊椎动物收费类受体 (TLR) 的进化揭示了在白纪灭绝事件期间具有适应性免疫力的基因增益和显著损失. 这项研究澄清了主要脊椎动物系的TLR多样性和命名法.
科学领域:
- 进化生物学是进化的生物学.
- 免疫学 免疫学 免疫学
- 基因组学就是基因组学.
背景情况:
- 通过RAG酶介导的适应性免疫反应在脊椎动物中得到了广泛的研究.
- 适应性免疫的进化对先天性免疫受体多样性的影响,特别是收费类受体 (TLRs),理解程度较低.
- TLRs是古老的,保存的先天免疫受体,在生命之树中至关重要.
研究的目的:
- 在适应性免疫系统进化的背景下,研究脊椎动物收费类受体 (TLR) 的多样化.
- 整合来自多种脊椎动物血统的基因组和转录组数据,包括早期的光鱼.
- 分析TLR基因增加和损失的进化模式,并解决命名规范上的差异.
主要方法:
- 跨主要脊椎动物血统的比较基因组学.
- 对多体 (早期的射线鱼) 的转录基因分析.
- 遗传学分析以确定TLR子家族和类.
- 对基因增加/损失事件的分析以及与地质事件的相关性.
主要成果:
- 识别了属于主要子家族 (TLR1,3,4,5,7,11) 和新型类的TLR序列.
- 观察到TLR基因增益的脉冲与脊椎动物适应性免疫 (RAG介导) 的出现相吻合.
- 在白纪期间,在海洋teleosts中记录了显著的TLR基因损失,与白纪中期的无氧事件有关.
- 在几个脊椎动物群体中,多达50%的TLR发现了名称不匹配.
结论:
- 脊椎动物TLR的进化是由适应性免疫和主要的环境事件所塑造的.
- 该研究提供了TLR多样性的全面观点,并强调了需要准确的基因注释和命名的必要性.
- 为未来研究非模型生物中的TLR功能和进化提供了一个框架.
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