Department of Plant Sciences, University of Cambridge, Cambridge CB2 3EA, United Kingdom; email:
Annu Rev Phytopathol. 2018 Aug 25;56:135-160. doi: 10.1146/annurev-phyto-080516-035521. Epub 2018 Jun 1.
Most land plants engage in mutually beneficial interactions with arbuscular mycorrhizal (AM) fungi, the fungus providing phosphate and nitrogen in exchange for fixed carbon. During presymbiosis, both organisms communicate via oligosaccharides and butenolides. The requirement for a rice chitin receptor in symbiosis-induced lateral root development suggests that cell division programs operate in inner root tissues during both AM and nodule symbioses. Furthermore, the identification of transcription factors underpinning arbuscule development and degeneration reemphasized the plant's regulatory dominance in AM symbiosis. Finally, the finding that AM fungi, as lipid auxotrophs, depend on plant fatty acids (FAs) to complete their asexual life cycle revealed the basis for fungal biotrophy. Intriguingly, lipid metabolism is also central for asexual reproduction and interaction of the fungal sister clade, the Mucoromycotina, with endobacteria, indicative of an evolutionarily ancient role for lipids in fungal mutualism.
大多数陆地植物与丛枝菌根（AM）真菌进行互利共生，真菌提供磷酸盐和氮，以换取固定碳。在共生前期，两种生物通过寡糖和丁烯内酯进行交流。水稻几丁质受体在共生诱导侧根发育中的作用表明，细胞分裂程序在 AM 和根瘤共生过程中都在根内组织中起作用。此外，鉴定出支持丛枝发育和退化的转录因子，再次强调了植物在 AM 共生中的调控主导地位。最后，发现 AM 真菌作为脂质营养缺陷型，依赖植物脂肪酸（FA）完成其无性生命周期，揭示了真菌生物营养的基础。有趣的是，脂质代谢对于无性繁殖和真菌姐妹类群（毛霉门）与内细菌的相互作用也很重要，表明脂质在真菌共生中的作用具有古老的进化意义。
