Cis到trans:通过进化出现的小ORF功能
Casimiro Baena-Angulo1, Ana Isabel Platero1, Juan Pablo Couso1
1Centro Andaluz de Biología del Desarrollo, CSIC, Universidad Pablo de Olavide, Carretera de Utrera Km1, Sevilla 41013, Spain.
Trends in genetics : TIG
|November 27, 2024
概括
数以千计的小型开放式阅读框架 (smORF) 已被翻译,并具有功能,而不是被丢弃为非功能. 这些smORF可以是调节性或编码性,其中一些从非编码序列进化为新基因.
科学领域:
- 基因组学就是基因组学.
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 小开放的读取 (smORF),通常在100个代码以下,在基因组中很丰富,特别是在长非编码RNA (lncRNA) 和mRNA 5'领导者中.
- 从历史上看,smORFs经常被忽视,并被认为是非功能性的.
- 新出现的证据表明,大量的smORF被积极翻译并具有生物学作用.
研究的目的:
- 调查翻译smORFs的功能意义和进化起源.
- 描述smORFs的不同作用,从cis-regulatory功能到代码能力.
- 提出一种机制,通过smORFs.通过非编码序列新基因的de novo进化.
主要方法:
- 利用核糖体分析 (RiboSeq) 在各种基因组环境中识别活跃翻译的smORF.
- 分析了smORF的功能特征,区分了调控和编码的作用.
- 研究了smORF的进化轨迹,以了解它们从非编码区域的出现.
主要成果:
- 核糖体分析证实,成千上万的smORFs被翻译,挑战他们以前被解雇为非功能性.
- 确定了smORF的两个主要功能类别:cis-noncoding调节作用和完整编码功能.
- 证明强烈翻译的smORF通常调解细胞和生理功能,包括作为膜相关调节者的角色.
- 进化分析表明,许多smORFs源自de novo的非编码序列.
结论:
- smORFs是功能性遗传元素的重要,以前被低估的来源.
- smORFs的双重功能 (调节和编码) 为新基因的进化提供了一条途径.
- smORFs的cis-noncoding功能可能作为进化前体,为随后的代码能力的发展创造了利基.
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