昆虫Mnemiopsis leidyi的基因组及其对细胞类型进化的影响
Joseph F Ryan1, Kevin Pang, Christine E Schnitzler
1Genome Technology Branch, Division of Intramural Research, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Science (New York, N.Y.)
|December 17, 2013
概括
(果) 基因组测序显示,它们可能是最早的动物血统,早于海绵. 这挑战了以前的进化模型,并表明神经和肌肉等复杂细胞类型的独立进化.
科学领域:
- * 进化的生物学
- * 基因组学 是一个学科.
- * * 海洋生物学 海洋生物学
背景情况:
- * 了解早期动物进化需要洞察基底血统.
- * 藻 (藻) 是解决家族遗传关系的关键.
- *以前的假设将海绵作为所有其他动物的姐妹群.
研究的目的:
- * 测序,组装,并注释的基因组的天虫 Mnemiopsis leidyi.
- * 进行基因组分析以确定所有其他动物的姐妹血统.
- * 研究细胞类型的进化起源,包括神经和肌肉细胞.
主要方法:
- * 全基因组测序和Mnemiopsis leidyi的组装.
- * 基因组学分析使用氨基酸位置和基因含量.
- *比较基因组学以确定基因家族和细胞类型特定的基因.
主要成果:
- * 遗传学分析支持花虫是所有其他动物的姐妹血统,挑战了传统的海绵-姐妹假设.
- * Mnemiopsis leidyi 基因组缺少双边中皮细胞类型的许多特征基因,这表明独立的进化.
- * Mnemiopsis 中的神经基因的集合与海绵相似,表明海绵中神经系统的潜在损失.
结论:
- * ,而不是海绵,可能代表了最早的分离的动物血统.
- *神经和肌肉等复杂细胞类型的进化在不同的血统中独立发生.
- *这项研究为了解早期动物进化提供了一个新的框架,包括细胞类型的显著损失和/或增长.
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