Quilbé Johan, Montiel Jesús, Arrighi Jean-François, Stougaard Jens
Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark.
Centre for Genomic Sciences, National Autonomous University of Mexico (UNAM), Cuernavaca, Mexico.
Front Plant Sci. 2022 Jun 23;13:922982. doi: 10.3389/fpls.2022.922982. eCollection 2022.
Establishment of the root-nodule symbiosis in legumes involves rhizobial infection of nodule primordia in the root cortex that is dependent on rhizobia crossing the root epidermal barrier. Two mechanisms have been described: either through root hair infection threads or through the intercellular passage of bacteria. Among the legume genera investigated, around 75% use root hair entry and around 25% the intercellular entry mode. Root-hair infection thread-mediated infection has been extensively studied in the model legumes and . In contrast, the molecular circuit recruited during intercellular infection, which is presumably an ancient and simpler pathway, remains poorly known. In recent years, important discoveries have been made to better understand the transcriptome response and the genetic components involved in legumes with obligate ( and spp.) and conditional ( and spp.) intercellular rhizobial infections. This review addresses these novel findings and briefly considers possible future research to shed light on the molecular players that orchestrate intercellular infection in legumes.
豆科植物根瘤共生关系的建立涉及根皮层中根瘤原基的根瘤菌感染，这依赖于根瘤菌穿过根表皮屏障。已描述了两种机制：要么通过根毛感染丝，要么通过细菌的细胞间通道。在所研究的豆科植物属中，约75%采用根毛侵入方式，约25%采用细胞间侵入方式。根毛感染丝介导的感染已在模式豆科植物和中得到广泛研究。相比之下，细胞间感染过程中所招募的分子回路，大概是一条古老且更简单的途径，仍然鲜为人知。近年来，为了更好地理解专性（和属物种）和条件性（和属物种）细胞间根瘤菌感染的豆科植物中的转录组反应和相关遗传成分，已取得了重要发现。本综述阐述了这些新发现，并简要考虑了未来可能的研究，以揭示协调豆科植物细胞间感染的分子参与者。
