Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i>
<i>Bradyrhizobium elkanii</i> USDA61 possesses a functional type III secretion system (T3SS) that controls host-specific symbioses with legumes. Here, we demonstrated that <i>B. elkanii</i> T3SS is essential for the nodulation of several southern Asiatic <i>Vigna mungo&...
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MDPI AG
2020-04-01
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| Series: | Genes |
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| Online Access: | https://www.mdpi.com/2073-4425/11/5/474 |
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| author | Hien P. Nguyen Safirah T. N. Ratu Michiko Yasuda Neung Teaumroong Shin Okazaki |
| author_facet | Hien P. Nguyen Safirah T. N. Ratu Michiko Yasuda Neung Teaumroong Shin Okazaki |
| author_sort | Hien P. Nguyen |
| collection | DOAJ |
| description | <i>Bradyrhizobium elkanii</i> USDA61 possesses a functional type III secretion system (T3SS) that controls host-specific symbioses with legumes. Here, we demonstrated that <i>B. elkanii</i> T3SS is essential for the nodulation of several southern Asiatic <i>Vigna mungo</i> cultivars. Strikingly, inactivation of either Nod factor synthesis or T3SS in <i>B. elkanii</i> abolished nodulation of the <i>V. mungo</i> plants. Among the effectors, NopL was identified as a key determinant for T3SS-dependent symbiosis. Mutations of other effector genes, such as <i>innB</i>, <i>nopP2</i>, and <i>bel2-5</i>, also impacted symbiotic effectiveness, depending on host genotypes. The <i>nopL</i> deletion mutant formed no nodules on <i>V. mungo,</i> but infection thread formation was still maintained, thereby suggesting its pivotal role in nodule organogenesis. Phylogenetic analyses revealed that NopL was exclusively conserved among <i>Bradyrhizobium</i> and <i>Sinorhizobium</i> (<i>Ensifer</i>) species and showed a different phylogenetic lineage from T3SS. These findings suggest that <i>V. mungo</i> evolved a unique symbiotic signaling cascade that requires both NFs and T3Es (NopL). |
| first_indexed | 2024-03-10T20:12:49Z |
| format | Article |
| id | doaj.art-ca06d9e5f16941fbbda128288b90ec41 |
| institution | Directory Open Access Journal |
| issn | 2073-4425 |
| language | English |
| last_indexed | 2024-03-10T20:12:49Z |
| publishDate | 2020-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Genes |
| spelling | doaj.art-ca06d9e5f16941fbbda128288b90ec412023-11-19T22:51:22ZengMDPI AGGenes2073-44252020-04-0111547410.3390/genes11050474Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i>Hien P. Nguyen0Safirah T. N. Ratu1Michiko Yasuda2Neung Teaumroong3Shin Okazaki4Institute of Global Innovation Research (IGIR), Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo 183-8538, JapanUnited Graduate School of Agricultural Science, TUAT, Fuchu, Tokyo 183-8509, JapanGraduate School of Agriculture, TUAT, Fuchu, Tokyo 183-8509, JapanSchool of Biotechnology, Institute of Agricultural Technology, Suranaree University of Technology (SUT), Ratchasima 30000, ThailandUnited Graduate School of Agricultural Science, TUAT, Fuchu, Tokyo 183-8509, Japan<i>Bradyrhizobium elkanii</i> USDA61 possesses a functional type III secretion system (T3SS) that controls host-specific symbioses with legumes. Here, we demonstrated that <i>B. elkanii</i> T3SS is essential for the nodulation of several southern Asiatic <i>Vigna mungo</i> cultivars. Strikingly, inactivation of either Nod factor synthesis or T3SS in <i>B. elkanii</i> abolished nodulation of the <i>V. mungo</i> plants. Among the effectors, NopL was identified as a key determinant for T3SS-dependent symbiosis. Mutations of other effector genes, such as <i>innB</i>, <i>nopP2</i>, and <i>bel2-5</i>, also impacted symbiotic effectiveness, depending on host genotypes. The <i>nopL</i> deletion mutant formed no nodules on <i>V. mungo,</i> but infection thread formation was still maintained, thereby suggesting its pivotal role in nodule organogenesis. Phylogenetic analyses revealed that NopL was exclusively conserved among <i>Bradyrhizobium</i> and <i>Sinorhizobium</i> (<i>Ensifer</i>) species and showed a different phylogenetic lineage from T3SS. These findings suggest that <i>V. mungo</i> evolved a unique symbiotic signaling cascade that requires both NFs and T3Es (NopL).https://www.mdpi.com/2073-4425/11/5/474symbiosisT3SSeffectorsNopL<i>Vigna mungo</i><i>Bradyrhizobium elkanii</i> |
| spellingShingle | Hien P. Nguyen Safirah T. N. Ratu Michiko Yasuda Neung Teaumroong Shin Okazaki Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> Genes symbiosis T3SS effectors NopL <i>Vigna mungo</i> <i>Bradyrhizobium elkanii</i> |
| title | Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> |
| title_full | Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> |
| title_fullStr | Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> |
| title_full_unstemmed | Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> |
| title_short | Identification of <i>Bradyrhizobium elkanii</i> USDA61 Type III Effectors Determining Symbiosis with <i>Vigna mungo</i> |
| title_sort | identification of i bradyrhizobium elkanii i usda61 type iii effectors determining symbiosis with i vigna mungo i |
| topic | symbiosis T3SS effectors NopL <i>Vigna mungo</i> <i>Bradyrhizobium elkanii</i> |
| url | https://www.mdpi.com/2073-4425/11/5/474 |
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