Send to

Choose Destination
Plant Cell. 2019 Oct;31(10):2386-2410. doi: 10.1105/tpc.18.00676. Epub 2019 Aug 15.

The Ectomycorrhizal Fungus Laccaria bicolor Produces Lipochitooligosaccharides and Uses the Common Symbiosis Pathway to Colonize Populus Roots.

Author information

Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706.
Department of Agronomy, University of Wisconsin, Madison, Wisconsin 53706.
Laboratoire de Recherche en Sciences Végétales, Université de Toulouse, CNRS, UPS, 31326, Castanet-Tolosan, France.
Department of Forest Ecosystems and Society, Oregon State University, Corvallis, Oregon 97331.
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831.
Department of Biology and Microbiology, South Dakota State University, Brookings, South Dakota 57007.
Laboratoire des Interactions Plantes-Microorganismes, Université de Toulouse, INRA, CNRS, 31326, Castanet-Tolosan, France.
Laboratoire Evolution et Diversité Biologique, Université de Toulouse, UPS, CNRS, IRD, 31077 Toulouse, France.
Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706


Mycorrhizal fungi form mutualistic associations with the roots of most land plants and provide them with mineral nutrients from the soil in exchange for fixed carbon derived from photosynthesis. The common symbiosis pathway (CSP) is a conserved molecular signaling pathway in all plants capable of associating with arbuscular mycorrhizal fungi. It is required not only for arbuscular mycorrhizal symbiosis but also for rhizobia-legume and actinorhizal symbioses. Given its role in such diverse symbiotic associations, we hypothesized that the CSP also plays a role in ectomycorrhizal associations. We showed that the ectomycorrhizal fungus Laccaria bicolor produces an array of lipochitooligosaccharides (LCOs) that can trigger both root hair branching in legumes and, most importantly, calcium spiking in the host plant Populus in a CASTOR/POLLUX-dependent manner. Nonsulfated LCOs enhanced lateral root development in Populus in a calcium/calmodulin-dependent protein kinase (CCaMK)-dependent manner, and sulfated LCOs enhanced the colonization of Populus by L. bicolor Compared with the wild-type Populus, the colonization of CASTOR/POLLUX and CCaMK RNA interference lines by L. bicolor was reduced. Our work demonstrates that similar to other root symbioses, L. bicolor uses the CSP for the full establishment of its mutualistic association with Populus.

Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center