蛋白质编码异构体的诞生是由LINE-1逆转移素的古代化产生的
Koichi Kitao1, Kenji Ichiyanagi2, So Nakagawa3,4,5
1Laboratory of Genome and Epigenome Dynamics, Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan; kitao.z7deb13@gmail.com so@tokai.ac.jp.
Genome research
|May 9, 2025
概括
LINE-1逆转移子已经被化到宿主基因中,产生了像Lyosin这样的新型蛋白质异型. 这项研究揭示了L1 ORF1pp.
科学领域:
- 基因组学和分子进化
- 基因调控和基因表达的调节和表达
背景情况:
- 转位子,特别是LINE-1 (L1) 元素,是脊椎动物中谱系特异性基因创新的重要驱动因素.
- 虽然L1元素丰富,但很少通过替代拼接报告它们被化为宿主蛋白质编码基因.
研究的目的:
- 识别和表征由L1逆转移子集成到宿主基因而产生的新型蛋白质异型.
- 研究这些转子子-宿主融合蛋白的进化史和潜在的适应性功能.
主要方法:
- 识别将L1逆转移素序列,特别是L1ORF1纳入宿主基因的剪接变异.
- 分子进化分析以确定已识别的异构体的起源和保存情况.
- 对不同组织和物种中新型转录的表达分析.
主要成果:
- 发现了一种新型的myosin光链4 (MYL4) 拼接变体,其中包含一个L1ORF1衍生的外子,称为"Lyosin".
- 氨酸起源于Sauropsida的分歧之前,并且一直在进行净化选择,尽管一些血统中的损失.
- 氨酸转录表达在爬行动物丸中,这表明与正规的MYL4.4区别的组织特异性功能.
- 在其他三种脊椎动物基因中确定了额外的L1ORF1融合拼接异型.
结论:
- 通过替代拼接,LINE-1逆转移素有助于通过替代拼接产生谱系特异性蛋白质.
- 在L1ORF1蛋白 (ORF1p) 之外,它在逆转换中的作用可能具有以前未知的适应功能.
- 转子子-宿主基因融合是脊椎动物进化中蛋白质新奇性的重要,但被低估的来源.
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