毒素基因的序列分歧在山地 (Viperidae:Crotalinae:Cerrophidion) 内部和之间物种是由突变漂移平衡驱动的
Ramses Alejandro Rosales-García1, Rhett M Rautsaw2, Erich P Hofmann2,3
1Department of Biological Sciences, Clemson University, 190 Collings St., Clemson, SC, 29634, USA. ramsesr@g.clemson.edu.
Journal of molecular evolution
|June 3, 2023
概括
蒙坦蛇的毒液成分在C. godmani和C. tzotzilorum等物种内有很大差异,这是由基因表达而不是选择驱动的. 这项研究强调了孤立群体中独特的毒素进化.
科学领域:
- 类学和进化生物学 进化生物学
- 分子生物学和基因组学
- 毒素的生物化学 毒素的生物化学
背景情况:
- 新世界的毒液成分多样化,但中美洲的山地 (Cerrophidion) 仍未得到充分研究.
- 与广泛传播的蛇相比,Cerrophidion的孤立种群可能表现出独特的毒液进化轨迹.
- 了解毒液变异对于生态和医学应用至关重要.
研究的目的:
- 描述了几个Cerrophidion物种的毒腺转录组,包括C. petlalcalensis,C. tzotzilorum,C. godmani和C. sasai.
- 研究Cerrophidion中的基因表达变异和毒素序列演变,重点关注C.godmani.
- 为了确定毒液的关键成分,并探索毒液内特定变化的驱动因素.
主要方法:
- 对C. petlalcalensis,C. tzotzilorum,C. godmani和C. sasai的种群进行了毒腺转录组测序.
- 对毒毒素的基因表达水平进行了量化,并在不同种群和物种中进行了比较.
- 进行了序列分析,以评估毒素的进化模式,特别是C. godmani.
主要成果:
- 蛇的毒腺主要由蛇毒金属蛋白酶,脂酶A2s (PLA2s) 和蛇毒血清蛋白酶组成.
- 在C. godmani和C. tzotzilorum中观察到毒素组成的显著内属变异,主要是由于基因表达的差异,而不是选择.
- 在大多数物种中发现了类似PLA2的髓毒素,在南方C.godmani种群中发现了类似毒素的PLA2,这表明潜在的神经毒性活性.
结论:
- 在某些Cerrophidion物种中,物种内毒的变异是相当大的,这是由基因表达的调节性变化所驱动的.
- 在C. godmani中,毒素的演变似乎遵循一种突变漂移平衡模型,对方向选择的证据有限.
- 在南方C. godmani中发现的类似毒素的PLA2s,需要进一步研究潜在的神经毒性毒素的特性.
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