TY - JOUR
T1 - Variation in bradyrhizobial NopP effector determines symbiotic incompatibility with Rj2-soybeans via effector-triggered immunity
AU - Sugawara, Masayuki
AU - Takahashi, Satoko
AU - Umehara, Yosuke
AU - Iwano, Hiroya
AU - Tsurumaru, Hirohito
AU - Odake, Haruka
AU - Suzuki, Yuta
AU - Kondo, Hitoshi
AU - Konno, Yuki
AU - Yamakawa, Takeo
AU - Sato, Shusei
AU - Mitsui, Hisayuki
AU - Minamisawa, Kiwamu
N1 - Funding Information:
We thank Professor Neung Teaumroong (Suranaree University of Technology) for providing mung bean seeds. We thank Dr. Cristina Sánchez and Mr. Shohei Kusakabe (Tohoku University) for advice on mutant construction and protein secretion assay, respectively. We are grateful to Ms. Kaori Kakizaki (Tohoku University) for technical supports in MiSeq sequencing of the spontaneous mutants, and to Mr. Tomoyuki Sakata (Kyushu University) for technical support in DNA sequencing of Is-1 mutants. We thank Dr. Michiko Yasuda (Tokyo University of Agriculture and Technology) and Dr. Yasuyuki Kawaharada (Iwate University) for advice on microscopic observation of soybean roots. This work was supported by JSPS KAKENHI Grant Numbers 26252065 (to K.M.) and 15K20868 (to M.S.) from the Ministry of Education, Culture, Sports, Science and Technology of Japan.
Publisher Copyright:
© 2018, The Author(s).
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Genotype-specific incompatibility in legume–rhizobium symbiosis has been suggested to be controlled by effector-triggered immunity underlying pathogenic host-bacteria interactions. However, the rhizobial determinant interacting with the host resistance protein (e.g., Rj2) and the molecular mechanism of symbiotic incompatibility remain unclear. Using natural mutants of Bradyrhizobium diazoefficiens USDA 122, we identified a type III-secretory protein NopP as the determinant of symbiotic incompatibility with Rj2-soybean. The analysis of nopP mutations and variants in a culture collection reveal that three amino acid residues (R60, R67, and H173) in NopP are required for Rj2-mediated incompatibility. Complementation of rj2-soybean by the Rj2 allele confers the incompatibility induced by USDA 122-type NopP. In response to incompatible strains, Rj2-soybean plants activate defense marker gene PR-2 and suppress infection thread number at 2 days after inoculation. These results suggest that Rj2-soybeans monitor the specific variants of NopP and reject bradyrhizobial infection via effector-triggered immunity mediated by Rj2 protein.
AB - Genotype-specific incompatibility in legume–rhizobium symbiosis has been suggested to be controlled by effector-triggered immunity underlying pathogenic host-bacteria interactions. However, the rhizobial determinant interacting with the host resistance protein (e.g., Rj2) and the molecular mechanism of symbiotic incompatibility remain unclear. Using natural mutants of Bradyrhizobium diazoefficiens USDA 122, we identified a type III-secretory protein NopP as the determinant of symbiotic incompatibility with Rj2-soybean. The analysis of nopP mutations and variants in a culture collection reveal that three amino acid residues (R60, R67, and H173) in NopP are required for Rj2-mediated incompatibility. Complementation of rj2-soybean by the Rj2 allele confers the incompatibility induced by USDA 122-type NopP. In response to incompatible strains, Rj2-soybean plants activate defense marker gene PR-2 and suppress infection thread number at 2 days after inoculation. These results suggest that Rj2-soybeans monitor the specific variants of NopP and reject bradyrhizobial infection via effector-triggered immunity mediated by Rj2 protein.
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U2 - 10.1038/s41467-018-05663-x
DO - 10.1038/s41467-018-05663-x
M3 - Article
C2 - 30087346
AN - SCOPUS:85051268411
SN - 2041-1723
VL - 9
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - 3139
ER -