经过处理的伪基因的进化动态的重建表明,在裸鼠中",逆生态组"的深度沉默
Valeria Kogan1, Ivan Molodtsov2, Daria I Fleyshman2
1Institute for Personalized and Translational Medicine, Adelson School of Medicine, Ariel University, Ariel 4070000, Israel.
概括
哺乳动物的基因组含有逆转移子,这些基因元素可以放大. 分析加工伪基因 (PPG) 揭示了近期在小鼠和老鼠中的高逆转移素活性,但在裸鼠中沉默的活性.
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:
- 哺乳动物的基因组在很大程度上是由反转移体,重复的遗传元素形成的.
- 逆转移体活性,称为"逆生体组",以放大和沉默相为特征.
- 处理伪基因 (PPG) 是mRNA的非功能性DNA副本,作为逆转移素活性标记物.
研究的目的:
- 通过对哺乳动物物种的加工伪基因 (PPG) 进行分析,研究逆转移子的进化动态.
- 用PPG突变率来评估逆转移体活性的强度和时间.
- 探索复原体活动与裸鼠 (NMR) 独特特征之间的潜在联系,例如寿命和抗癌能力.
主要方法:
- 从小鼠,老鼠和裸鼠 (NMR) 的DNA中分析加工伪基因 (PPG) 比例和突变水平.
- 将PPG与其祖先的信使RNA (mRNA) 序列进行比较,以确定遗传偏差的程度.
- 在一系列哺乳动物物种中进行比较基因组分析,以确定PPG进化的模式.
主要成果:
- 小鼠和老鼠表现出高比例的年轻PPG,表明最近和显著的逆转移素活性.
- 裸鼠 (NMR) 基因组显示了高度分歧的PPG,最近的插入很少,这表明其最近的进化过去有一个沉默的逆生态组.
- 单一小鼠菌株 (C57BL/6) 中PPG含量的多样性证实了生殖系中持续存在的逆转移素活性.
结论:
- 这项研究揭示了哺乳动物进化中逆转移素活性的独特模式,最近在动物中出现了突发事件,并且在NMR中出现了显著的沉默.
- 核磁共振中的独特复原体动力学可能与其特殊的寿命和抗癌能力有关.
- 需要进一步研究逆转移体,衰老和癌症之间的相互作用.
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