Premium
Local endoreduplication as a feature of intracellular fungal accommodation in arbuscular mycorrhizas
Author(s) -
Carotenuto Gennaro,
Volpe Veronica,
Russo Giulia,
Politi Mara,
Sciascia Ivan,
AlmeidaEngler Janice,
Genre Andrea
Publication year - 2019
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.15763
Subject(s) - endoreduplication , biology , medicago truncatula , microbiology and biotechnology , colonization , intracellular , symbiosis , botany , genetics , gene , cell cycle , bacteria
Summary The intracellular accommodation of arbuscular mycorrhizal ( AM ) fungi is a paradigmatic feature of this plant symbiosis that depends on the activation of a dedicated signaling pathway and the extensive reprogramming of host cells, including striking changes in nuclear size and transcriptional activity. By combining targeted sampling of early root colonization sites, detailed confocal imaging, flow cytometry and gene expression analyses, we demonstrate that local, recursive events of endoreduplication are triggered in the Medicago truncatula root cortex during AM colonization. AM colonization induces an increase in ploidy levels and the activation of endocycle specific markers. This response anticipates the progression of fungal colonization and is limited to arbusculated and neighboring cells in the cortical tissue. Furthermore, endoreduplication is not induced in M. truncatula mutants for symbiotic signaling pathway genes. On this basis, we propose endoreduplication as part of the host cell prepenetration responses that anticipate AM fungal accommodation in the root cortex.