Center for Viticulture and Small Fruit Research, College of Agriculture and Food Sciences, Florida A&M University, Tallahassee, FL 32308, USA.
Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA.
Int J Mol Sci. 2021 Sep 28;22(19):10446. doi: 10.3390/ijms221910446.
While horizontally transferred transposable elements (TEs) have been reported in several groups of plants, their importance for genome evolution remains poorly understood. To understand how horizontally transferred TEs contribute to plant genome evolution, we investigated the composition and activity of horizontally transferred TEs in the genomes of four species. A total of 35 horizontal transfer (HT) events were identified between the four species and 21 other plant species belonging to 14 different families. We determined the donor and recipient species for 28 of these HTs, with the species being recipients of 15 of them. As a result of HTs, 8-10 LTR retrotransposon clusters were newly formed in the genomes of the four species. The activities of the horizontally acquired LTR retrotransposons differed among species, showing that the consequences of HTs vary during the diversification of the recipient lineage. Our study provides the first evidence that the HT of TEs contributes to the diversification of plant genomes by generating additional TE subfamilies and causing their differential proliferation in host genomes.
虽然已经在几个植物群中报道了水平转移的转座元件（TEs），但其对基因组进化的重要性仍知之甚少。为了了解水平转移的 TEs 如何促进植物基因组进化，我们研究了四个 物种的基因组中水平转移的 TEs 的组成和活性。在这四个 物种和 21 个属于 14 个不同科的其他植物物种之间共鉴定出 35 个水平转移（HT）事件。我们确定了其中 28 个 HT 的供体和受体物种，其中 15 个是 物种的受体。由于 HTs 的发生，四个 物种的基因组中新形成了 8-10 个 LTR 反转录转座子簇。水平获得的 LTR 反转录转座子的活性在 物种之间存在差异，表明 HTs 的后果在受体谱系的多样化过程中有所不同。我们的研究首次提供了证据，表明 TEs 的 HT 通过产生额外的 TE 亚家族并导致它们在宿主基因组中的差异增殖，从而促进了植物基因组的多样化。
