Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA, 94720, USA,
Chromosome Res. 2013 Dec;21(6-7):587-600. doi: 10.1007/s10577-013-9394-4.
Transposons are mobile genetic elements that are a major constituent of most genomes. Organisms regulate transposable element expression, transposition, and insertion site preference, mitigating the genome instability caused by uncontrolled transposition. A recent burst of research has demonstrated the critical role of small non-coding RNAs in regulating transposition in fungi, plants, and animals. While mechanistically distinct, these pathways work through a conserved paradigm. The presence of a transposon is communicated by the presence of its RNA or by its integration into specific genomic loci. These signals are then translated into small non-coding RNAs that guide epigenetic modifications and gene silencing back to the transposon. In addition to being regulated by the host, transposable elements are themselves capable of influencing host gene expression. Transposon expression is responsive to environmental signals, and many transposons are activated by various cellular stresses. TEs can confer local gene regulation by acting as enhancers and can also confer global gene regulation through their non-coding RNAs. Thus, transposable elements can act as stress-responsive regulators that control host gene expression in cis and trans.
转座子是移动的遗传元件，是大多数基因组的主要组成部分。生物调节转座子的表达、转座和插入位点偏好，减轻了由不受控制的转座引起的基因组不稳定性。最近的大量研究表明，小非编码 RNA 在调控真菌、植物和动物中的转座起着关键作用。虽然在机制上有所不同，但这些途径通过一个保守的范例发挥作用。转座子的存在通过其 RNA 的存在或其整合到特定的基因组位置来传达。然后，这些信号被翻译成小非编码 RNA，指导表观遗传修饰和基因沉默回到转座子。除了受到宿主的调控外，转座元件本身也能够影响宿主基因的表达。转座子的表达对环境信号有反应，许多转座子被各种细胞应激激活。转座子可以通过作为增强子来进行局部基因调控，也可以通过它们的非编码 RNA 来进行全局基因调控。因此，转座元件可以作为应激反应调节剂，在顺式和反式调节宿主基因的表达。
