在两种Gerbillinae物种中,构成染色体位点特异异染色体的高度重复性DNA序列的多样性和进化
Yoshinobu Uno1, Kazumi Matsubara2, Jun Inoue3,4
1Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan.
Cytogenetic and genome research
|September 14, 2023
概括
在Gerbillinae动物中研究重复性DNA揭示了异种染色素的快速演变. 特定的序列显示在Gerbillinae中保存,而其他,如逆转移子,在更广泛的哺乳动物群体中保存.
科学领域:
- 基因组学就是基因组学.
- 进化生物学 进化生物学
- 分子遗传学 分子遗传学
背景情况:
- 构成性的异染色质,富含重复性DNA,迅速进化,甚至在密切相关的物种之间也存在显著差异.
- 在Gerbillinae物种,Meriones unguiculatus和Gerbillus perpallidus中,染色体C带模式表现出很大的差异.
研究的目的:
- 为了阐明C阳性异染色素在Gerbillinae物种中的进化动态.
- 识别和描述高度重复的DNA序列及其在M. unguiculatus和G. perpallidus中的染色体分布.
主要方法:
- 从M. unguiculatus和G. perpallidus中分离和核酸测序高度重复的DNA序列.
- 染色体映射和过混合技术用于序列表征.
- 生物信息分析以确定序列同源性和进化起源.
主要成果:
- 确定了特定物种的重复 (M. unguiculatus中的MUN-HaeIII,MUN-EcoRI) 和中心/周中心重复 (G. perpallidus中的GPE-MBD).
- 在GPE-MBD中发现了一种对结合CENP-B至关重要的基因,这表明它在中间体功能中的作用.
- 发现大多数孤立序列 (除了GPE-EcoRI) 在Gerbillinae中保存,而GPE-EcoRI,LINE-1逆转移素衍生物,在Muridae和Cricetidae中显示同质性.
结论:
- 这项研究提供了对异色染色体的快速分歧和动物不同重复性DNA家族的独特进化轨迹的见解.
- 这些发现突出了某些逆转移素衍生的序列的古代起源,早于主要动物家族的分歧.
- 这项研究为了解哺乳动物中重复序列的演变提供了有价值的数据,特别是考虑到整个基因组组合中这种数据的稀缺性.
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