As the representative strain of Xanthomonas oryzae pv. oryzae (Xoo) China race 6, OS198 displayed low virulence in 26 rice varieties. talR26.5 is a transcription activatorlike (tal) gene cloned from the genomic DNA of OS198. TALR26.5 had 26.5 tandemrepeats of 34 amino acid residues and shared over 99% homology with the TAL effectors AvrXa73M of Philippines strain PXO357 and YP_451895 of Japanese strain MAFF 311018. The repeat domains were identical for the three proteins. The introduction of talR26.5 into PXO99A decreased the virulence and suppressed the bacterial populations in three nearisogenic rice lines IRBB8,IRBB14 and IRBB214 compared with the wild type PXO99A. The transformant strains showed no difference of virulence with PXO99A in 22 other rice varieties including IRBB7. The induced resistance of IRBB8, IRBB14 and IRBB214 against the infection of PXO99A harboring talR26.5 was implemented by the suppression of disease susceptibility gene Os8N3. PXO99A/talR26.5 aroused enhanced hypersensitive response in tobacco leaves compared with PXO99A. The results indicated that the talR26.5 gene of OS198 might have dual functions of virulence and avirulence.
ZHU Yinyin, LIU Yongting, LI Shihe, SONG Congfeng*
. Cloning and Functional Characterization of talR26.5 Gene from Xanthomonas oryzae pv. oryzae OS198 Strain[J]. Chinese Journal OF Rice Science, 2014
, 28(4)
: 343
-350
.
DOI: 10.3969/j.issn.1001-7216.2014.04.002
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