Sigman Meredith J, Slotkin R Keith
Department of Molecular Genetics and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210.
Department of Molecular Genetics and Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210
Plant Cell. 2016 Feb;28(2):304-13. doi: 10.1105/tpc.15.00869. Epub 2016 Feb 11.
Transposable elements (TEs) are mobile units of DNA that comprise large portions of plant genomes. Besides creating mutations via transposition and contributing to genome size, TEs play key roles in chromosome architecture and gene regulation. TE activity is repressed by overlapping mechanisms of chromatin condensation, epigenetic transcriptional silencing, and targeting by small interfering RNAs. The specific regulation of different TEs, as well as their different roles in chromosome architecture and gene regulation, is specified by where on the chromosome the TE is located: near a gene, within a gene, in a pericentromere/TE island, or at the centromere core. In this Review, we investigate the silencing mechanisms responsible for inhibiting TE activity for each of these chromosomal contexts, emphasizing that chromosomal location is the first rule dictating the specific regulation of each TE.
转座元件（TEs）是DNA的可移动单位，构成了植物基因组的大部分。除了通过转座产生突变并影响基因组大小外，TEs在染色体结构和基因调控中也发挥着关键作用。TE活性通过染色质凝聚、表观遗传转录沉默和小干扰RNA靶向等重叠机制受到抑制。不同TEs的具体调控，以及它们在染色体结构和基因调控中的不同作用，由TE在染色体上的位置决定：靠近基因、在基因内、在着丝粒周围/TE岛或着丝粒核心。在本综述中，我们研究了负责抑制这些染色体背景中每个TE活性的沉默机制，强调染色体位置是决定每个TE具体调控的首要规则。
