类精子的进化修饰与发育模式相关: (直接发育/发育进化/海/精子形态/基因组大小)
Rudolf A Raff1, Louis Herlands1, Valerie B Morris2
1Institute for Molecular and Cellular Biology, and Department of Biology, Indiana University, Bloomington, Indiana 47405, USA.
Development, growth & differentiation
|June 7, 2023
概括
直接发育的海进化出更大的卵子和长长的精子. 这项研究揭示了海体内雌激素的共同进化,将卵子大小与直接发育中的精子头形态联系起来.
科学领域:
- 海洋生物学 海洋生物学
- 发展生物学 发展生物学
- 进化生物学 进化生物学
背景情况:
- 许多海刺物种绕过了虫幼虫阶段,直接从胚胎发展到成年.
- 直接发育的海起源于大型漂浮的蛋,这是一个显著的进化转变.
- 这种直接的发展往往与改变的雌同体形态学有关.
研究的目的:
- 为了研究直接发育的海蛋蛋大小和精子形态之间的关系.
- 为了比较直接发育和飞阶段发育的同源物种之间的性质特征.
- 探索在类动物中直接发育的进化过程中,性子的潜在共同进化.
主要方法:
- 在两种Heliocidaris物种中,对精子头形态的比较分析 (直接开发者与浮动开发者).
- 精子基因组的电泳分析,以确定相关的蛋白质.
- 流式细胞测量以确定和比较平分体基因组大小.
主要成果:
- 直接发育的物种Heliocidaris erythrogramma,与状物种Heliocidaris tuberculata (5.6微米) 相比,具有延长的精子头 (11微米).
- 在直接开发者中没有发现不寻常的精子基因组或原蛋白.
- 红的单体基因组大小 (1.3 pg) 比结核 (0.95 pg) 更大.
- 其他直接发育的 echinoids 也表现出延长的精子头,支持一个共同的进化模式.
结论:
- 在直接发育的海中,大卵的进化伴随着长长的精子头的进化.
- 雌性体的共同进化似乎是类动物直接发育进化的共同特征.
- 这项研究强调了一种保存的进化策略,涉及海直接发育过程中的配体修饰.
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