Positive Gene Regulation by a Natural Protective miRNA Enables Arbuscular Mycorrhizal Symbiosis
Positive Gene Regulation by a Natural Protective miRNA Enables Arbuscular Mycorrhizal Symbiosis
复制标题
DOI：
10.1016/j.chom.2016.12.001
复制
发表时间：
2017-01-11
影响因子：
30.3
通讯作者：
Combier, Jean-Philippe
中科院分区：
文献类型：
--
作者：
Couzigou, Jean-Malo;Lauressergues, Dominique;Combier, Jean-Philippe
丛枝菌根（AM）共生关系将大多数植物与球囊菌门的真菌联系在一起。真菌会渗透到根部，并在皮层细胞内形成称为丛枝的分支结构，用于营养交换。我们发现miR171b具有错配的切割位点，并且不能下调miR171家族靶基因LOM1（LOST MERISTEMS 1）。这种不匹配的切割位点在建立AM共生的植物中是保守的，但在非真菌营养型植物中不是。与miR171家族的其他成员不同，miR171b刺激AM共生，并在含有丛枝的根细胞中特异性表达。MiR171b保护LOM 1免受其他miR171家族成员的负调控。这些发现揭示了一个独特的机制，积极的转录后调节基因表达的miRNA，并证明其相关的AM共生的建立。
Arbuscular mycorrhizal (AM) symbiosis associates most plants with fungi of the phylum Glomeromycota. The fungus penetrates into roots and forms within cortical cell branched structures called arbuscules for nutrient exchange. We discovered that miR171b has a mismatched cleavage site and is unable to downregulate the miR171 family target gene, LOM1 (LOST MERISTEMS 1). This mismatched cleavage site is conserved among plants that establish AM symbiosis, but not in non-mycotrophic plants. Unlike other members of the miR171 family, miR171b stimulates AM symbiosis and is expressed specifically in root cells that contain arbuscules. MiR171b protects LOM1 from negative regulation by other miR171 family members. These findings uncover a unique mechanism of positive post-transcriptional regulation of gene expression by miRNAs and demonstrate its relevance for the establishment of AM symbiosis.