Glomeromycotina is a lineage of early diverging fungi that establish arbuscular mycorrhizal ( We compared the genomes of Glomerales ( Genomic features in Glomeromycotina appear to be very similar with a very high content in transposons and protein‐coding genes, extensive duplications of protein kinase genes, and loss of genes coding for lignocellulose degradation, thiamin biosynthesis and cytosolic fatty acid synthase. Most symbiosis‐related genes in The high interspecific diversity of Glomeromycotina gene repertoires, affecting all known protein domains, as well as symbiosis‐related orphan genes, may explain the known adaptation of Glomeromycotina to a wide range of environmental settings. Our findings contribute to an increasingly detailed portrait of genomic features defining the biology of
Arbuscular mycorrhizal (AM) symbiosis is accompanied by alterations to root cell metabolism and physiology, and to the pathways of orthophosphate (Pi) entry into the root, which increase with Pi delivery to cortical cells via arbuscules. How AM symbiosis influences the Pi content and Pi response dynamics of cells in the root cortex and epidermis is unknown. Using fluorescence resonance energy transfer (FRET)‐based Pi biosensors, we mapped the relative cytosolic and plastidic Pi content of Colonized cortical cells had a higher cytosolic Pi content relative to noncolonized cortical and epidermal cells, while plastidic Pi content was highest in cells at the infection front. Pi application to the entire mycorrhizal root resulted in transient changes in cytosolic Pi that differed in direction and magnitude depending on cell type and arbuscule status; cells with mature arbuscules showed a substantial transient increase in cytosolic Pi while those with collapsed arbuscules showed a decrease. Directed Pi application to extraradical hyphae resulted in measurable changes in cytosolic Pi of colonized cells 18 h after application. Our experiments reveal that cells within a mycorrhizal root vary in Pi content and Pi response dynamics.
- NSF-PAR ID:
- 10366728
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 234
- Issue:
- 5
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 1817-1831
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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