TY - JOUR
T1 - The TIR-NBS but not LRR domains of two novel N-like proteins are functionally competent to induce the elicitor p50-dependent hypersensitive response
AU - Gao, Jun Shan
AU - Sasaki, Nobumitsu
AU - Kanegae, Hiromi
AU - Konagaya, Ken ichi
AU - Takizawa, Kaori
AU - Hayashi, Naomi
AU - Okano, Yosuke
AU - Kasahara, Masahiro
AU - Matsushita, Yasuhiko
AU - Nyunoya, Hiroshi
N1 - Funding Information:
We thank Yuko Takahashi for technical assistance. This work was supported by the grant-in-aid for Young Scientists (start-up) (to N. S.; no. 18880010), grant-in-aid for Scientific Research on Priority Areas (to H. N.; no. 15028206) and grant-in-aid for Scientific Research (C) (to H. N.; no. 17580038) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. It was also supported by a grant-in-aid from the Research for the Future program of the Japan Society for the Promotion of Science.
PY - 2007/7
Y1 - 2007/7
N2 - The tobacco N protein recognizes the helicase domain (p50) of the Tobacco mosaic virus (TMV) replicase as an elicitor and mediates hypersensitive response (HR). We obtained two cDNA clones encoding novel N-like (NL) proteins NL-C26 and NL-B69 from Nicotiana tabacum cv. Samsun NN. NL-C26 and NL-B69 had a Toll-interleukin-1 receptor/nucleotide-binding site/leucine-rich repeat (TIR-NBS-LRR) structure and showed 78% and 73% identities to N, respectively. The NL-C26 and NL-B69 genes were also expressed in N. tabacum cv. Samsun nn, which lacks the N gene. Unlike N, NL-C26 and NL-B69, when coexpressed with p50, failed to induce HR on the sites of agroinfiltration in Samsun nn leaves. However, the elicitor-dependent HR in Samsun nn was induced efficiently by chimeric N proteins with the continuous TIR-NBS domains of NL-C26 and NL-B69. On the other hand, the efficiency of HR induction varied significantly among chimeric N proteins with either of the TIR and NBS domains of the NL proteins. In contrast, chimeras carrying the LRR domains of the NL proteins did not induce HR. Thus, the TIR-NBS domains of NL-C26 and NL-B69 could functionally adapt to the LRR domain of N, which may determine the specificity for the elicitor. We speculate that the NL genes are potential HR-inducing resistance genes for undetermined pathogens other than TMV.
AB - The tobacco N protein recognizes the helicase domain (p50) of the Tobacco mosaic virus (TMV) replicase as an elicitor and mediates hypersensitive response (HR). We obtained two cDNA clones encoding novel N-like (NL) proteins NL-C26 and NL-B69 from Nicotiana tabacum cv. Samsun NN. NL-C26 and NL-B69 had a Toll-interleukin-1 receptor/nucleotide-binding site/leucine-rich repeat (TIR-NBS-LRR) structure and showed 78% and 73% identities to N, respectively. The NL-C26 and NL-B69 genes were also expressed in N. tabacum cv. Samsun nn, which lacks the N gene. Unlike N, NL-C26 and NL-B69, when coexpressed with p50, failed to induce HR on the sites of agroinfiltration in Samsun nn leaves. However, the elicitor-dependent HR in Samsun nn was induced efficiently by chimeric N proteins with the continuous TIR-NBS domains of NL-C26 and NL-B69. On the other hand, the efficiency of HR induction varied significantly among chimeric N proteins with either of the TIR and NBS domains of the NL proteins. In contrast, chimeras carrying the LRR domains of the NL proteins did not induce HR. Thus, the TIR-NBS domains of NL-C26 and NL-B69 could functionally adapt to the LRR domain of N, which may determine the specificity for the elicitor. We speculate that the NL genes are potential HR-inducing resistance genes for undetermined pathogens other than TMV.
KW - Elicitor
KW - HR
KW - Hypersensitive response
KW - N gene
KW - N homolog
KW - Nicotiana tabacum
KW - Samsun
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U2 - 10.1016/j.pmpp.2007.11.002
DO - 10.1016/j.pmpp.2007.11.002
M3 - Article
AN - SCOPUS:40849083513
SN - 0885-5765
VL - 71
SP - 78
EP - 87
JO - Physiological and Molecular Plant Pathology
JF - Physiological and Molecular Plant Pathology
IS - 1-3
ER -