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Interfering TAL effectors of Xanthomonas oryzae neutralize R-gene-mediated plant disease resistance.pdf

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Interfering TAL effectors of Xanthomonas oryzae neutralize R-gene-mediated plant disease resistance

Plant pathogenic bacteria of the genus Xanthomonas possess transcription activator-like effectors (TALEs) that activate transcription of disease susceptibility genes in the host, inducing a state of disease. Here we report that some isolates of the rice pathogen Xanthomonas oryzae use truncated versions of TALEs (which we term interfering TALEs, or iTALEs) to overcome disease resistance. In comparison with typical TALEs, iTALEs lack a transcription activation domain but retain nuclear localization motifs and are expressed from genes that were previously considered pseudogenes. We show that the rice gene Xa1, encoding a nucleotide-binding leucine-rich repeat protein, confers resistance against X. oryzae isolates by recognizing multiple TALEs. However, the iTALEs present in many isolates interfere with the otherwise broad-spectrum resistance conferred by Xa1. Our findings illustrate how bacterial effectors that trigger disease resistance in the host can evolve to interfere with the resistance process and, thus, promote disease.

Xanthomonas속 식물 병원성 박테리아는 숙주의 질병 감수성 유전자의 전사를 활성화시키는 transcription activator-like effectors(TAIL)를 가지고 있어 질병을 일으킨다.  Rice pathogen인 Xantomonasoryzae의 일부 isolate는 식물의 질병 내성을 억제하기 위해 TALE(interfering TALE 또는 iTALL이라고 함)의 잘린 버전을 사용한다. 일반적인 TAIL과 비교하여 iTALL은 transcription activation domain이 없지만 nuclear localization motifs를 유지하며, pseudogenes으로 간주되었던 유전자에서 발현된다. 이 논문은 nucleotide-binding leucine-rich repeat protein을 인코딩하는 쌀 유전자 Xa1이 여러 TAIL을 인식하여 X.oryzae isolate에 저항성을 부여하는 것을 보여준다. 이 논문의 연구결과는 숙주의 질병저항성을 유발하는 박테리아 effector들이 어떻게 진화하여 식물이 질병에 저항하는 과정을 방해해 질병을 촉진할 수 있는지 보여주고 있다.