左向右逆转反复演变,不管与透光相关的Formin基因重复或牛中的损失
Takeshi Noda1,2, Noriyuki Satoh3, Edmund Gittenberger4,5
1Department of Biology, Faculty of Science, Shinshu University, Matsumoto, Japan. takeshi.noda@oist.jp.
Journal of molecular evolution
|September 25, 2023
概括
胃类动物的卷轴手性,与其他动物不同,显示反转. 发现以前假设驱动 dextrallity 的 formin (diaph) 基因重复,已经独立地发生了多次,并且对于逆向进化来说并不重要.
科学领域:
- 发展生物学 发展生物学
- 进化遗传学 进化遗传学
- 胃类动物生物学 胃类动物生物学
背景情况:
- 双胞胎通常表现出保守的左右身体不对称性.
- 胃足动物 (牛) 是一个值得注意的例外,表现出不同的卷轴手性 (右侧/左侧).
- 以前的研究表明,与隔膜相关的formin (diaph) 基因重复可能与右侧线圈进化有关.
研究的目的:
- 为了研究脚动物手性中介质基因复制的进化作用.
- 确定隔膜重复是否是右侧或左侧反转演变的关键驱动因素.
主要方法:
- 在类动物谱系中对隔膜基因重复和损失事件的遗传学分析.
- 在左侧和右侧的胃类动物群体中对隔膜基因存在的比较分析.
- 在Lymnaea和Bradybaena中检查胚胎发育和基因表达.
主要成果:
- 隔膜基因复制至少独立发生了四次,在胃类动物中丢失了两次.
- 布雷迪贝纳的右撇子似乎是祖先的,而林尼亚的右撇子是衍生的.
- 左侧血统不断地进化,而不管隔膜基因复制状态如何.
- 隔膜重复物在细胞骨动力学中起着至关重要的作用,缺少表达会导致胚胎死亡.
- 腹膜重复或损失在胃类动物手性逆转的进化中没有起到主要作用.
结论:
- 将隔膜基因重复与右手的进化联系在一起的假设被驳斥了.
- 胃足类手性进化更复杂,涉及独立于隔膜重复的反复逆转.
- 隔膜复制品在胚胎发育中保留了基本的作用,不仅仅是控制身体的手性.
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