Centre for AgriBioscience, Agriculture Victoria, AgriBio, Bundoora, VIC, 3086, Australia.
School of Applied Systems Biology, La Trobe University, Bundoora, VIC, 3086, Australia.
Sci Rep. 2020 Nov 16;10(1):19883. doi: 10.1038/s41598-020-76478-4.
Evidence for ancestral gene transfer between Epichloë fungal endophyte ancestors and their host grass species is described. From genomes of cool-season grasses (the Poeae tribe), two Epichloë-originated genes were identified through DNA sequence similarity analysis. The two genes showed 96% and 85% DNA sequence identities between the corresponding Epichloë genes. One of the genes was specific to the Loliinae sub-tribe. The other gene was more widely conserved in the Poeae and Triticeae tribes, including wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). The genes were independently transferred during the last 39 million years. The transferred genes were expressed in plant tissues, presumably retaining molecular functions. Multiple gene transfer events between the specific plant and fungal lineages are unique. A range of cereal crops is included in the Poeae and Triticeae tribes, and the Loliinae sub-tribe is consisted of economically important pasture and forage crops. Identification and characterisation of the 'natural' adaptation transgenes in the genomes of cereals, and pasture and forage grasses, that worldwide underpin the production of major foods, such as bread, meat, and milk, may change the 'unnatural' perception status of transgenic and gene-edited plants.
描述了内生真菌祖先与其宿主草本植物之间祖先基因转移的证据。通过 DNA 序列相似性分析，从冷季草（Poaceae 族）基因组中鉴定出两个源自 Epichloë 的基因。这两个基因在相应的 Epichloë 基因之间具有 96%和 85%的 DNA 序列同一性。其中一个基因是 Loliinae 亚族特有的。另一个基因在 Poaceae 和 Triticeae 族中更为保守，包括小麦（Triticum aestivum L.）和大麦（Hordeum vulgare L.）。这些基因是在过去 3900 万年内独立转移的。转移的基因在植物组织中表达，推测保留了分子功能。在特定植物和真菌谱系之间发生的多次基因转移事件是独特的。Poaceae 和 Triticeae 族包括多种谷类作物，而 Loliinae 亚族则由具有经济重要性的牧场和饲料作物组成。鉴定和表征谷类作物、牧场和饲料草基因组中的“自然”适应转基因，这些基因在全球范围内为面包、肉类和牛奶等主要食品的生产提供了基础，这可能会改变对转基因和基因编辑植物的“非自然”看法。
