Populus trichocarpa encodes small, effector-like secreted proteins that are highly induced during mutualistic symbiosis.
During symbiosis, organisms use a range of metabolic and protein-based signals to communicate. Of these protein signals, one class is defined as 'effectors', i.e., small secreted proteins (SSPs) that cause phenotypical and physiological changes in another organism. To date, protein-based effectors have been described in aphids, nematodes, fungi and bacteria. Using RNA sequencing of Populus trichocarpa roots in mutualistic symbiosis with the ectomycorrhizal fungus Laccaria bicolor, we sought to determine if host plants also contain genes encoding effector-like proteins. We identified 417 plant-encoded putative SSPs that were significantly regulated during this interaction, including 161 SSPs specific to P. trichocarpa and 15 SSPs exhibiting expansion in Populus and closely related lineages. We demonstrate that a subset of these SSPs can enter L. bicolor hyphae, localize to the nucleus and affect hyphal growth and morphology. We conclude that plants encode proteins that appear to function as effector proteins that may regulate symbiotic associations.
INRA, UMR 1136 INRA-University of Lorraine, Interactions Arbres/Microorganismes, Laboratory of Excellence ARBRE, INRA-Nancy, 54280, Champenoux, France.|Hawkesbury Institute for the Environment, University of Western Sydney, Richmond, 2753, NSW, Australia.
Jonathan M
JM
Plett
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Hengfu
0000-0002-0720-5311
H
Yin
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Ritesh
0000-0002-0153-2434
R
Mewalal
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Rongbin
0000-0001-5921-6891
R
Hu
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Ting
T
Li
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Priya
P
Ranjan
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Sara
S
Jawdy
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Henrique C
0000-0001-8494-0603
HC
De Paoli
Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, 37996, USA.
George
G
Butler
Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, 37996, USA.
Tessa Maureen
TM
Burch-Smith
Department of Biochemistry & Cellular and Molecular Biology, University of Tennessee, Knoxville, TN, 37996, USA.
Hao-Bo
HB
Guo
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Chun
C
Ju Chen
INRA, UMR 1136 INRA-University of Lorraine, Interactions Arbres/Microorganismes, Laboratory of Excellence ARBRE, INRA-Nancy, 54280, Champenoux, France.
Annegret
A
Kohler
Hawkesbury Institute for the Environment, University of Western Sydney, Richmond, 2753, NSW, Australia.
Ian C
IC
Anderson
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Jessy L
0000-0003-0368-2054
JL
Labbé
INRA, UMR 1136 INRA-University of Lorraine, Interactions Arbres/Microorganismes, Laboratory of Excellence ARBRE, INRA-Nancy, 54280, Champenoux, France.
Francis
0000-0002-4737-3715
F
Martin
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
Gerald A
GA
Tuskan
Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA. yangx@ornl.gov.
Xiaohan
0000-0001-5207-4210
X
Yang
D002467:Cell Nucleus / Q000378:metabolism; D055399:Laccaria / Q000254:growth & development / Q000502:physiology*; D008954:Models, Biological; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D032107:Populus / Q000235:genetics / Q000382:microbiology / Q000502:physiology*; D013559:Symbiosis