@article{fdi:010084255,
  title = {{TAL} effectors with avirulence activity in {A}frican strains of {X}anthomonas oryzae pv. oryzae},
  author = {{L}achaux, {M}. and {T}homas, {E}. and {B}ogdanove, {A}. {J}. and {S}zurek, {B}oris and {H}utin, {M}athilde},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground {X}anthomonas oryzae pv. oryzae ({X}oo) causes bacterial leaf blight, a devastating disease of rice. {A}mong the type-3 effectors secreted by {X}oo to support pathogen virulence, the {T}ranscription {A}ctivator-{L}ike {E}ffector ({TALE}) family plays a critical role. {S}ome {TALE}s are major virulence factors that activate susceptibility ({S}) genes, overexpression of which contributes to disease development. {H}ost incompatibility can result from {TALE}-induced expression of so-called executor ({E}) genes leading to a strong and rapid resistance response that blocks disease development. {I}n that context, the {TALE} functions as an avirulence ({A}vr) factor. {T}o date no such avirulence factors have been identified in {A}frican strains of {X}oo. {R}esults {W}ith respect to the importance of {TALE}s in the {R}ice-{X}oo pathosystem, we aimed at identifying those that may act as {A}vr factor within {A}frican {X}oo. {W}e screened 86 rice accessions, and identified 12 that were resistant to two {A}frican strains while being susceptible to a well-studied {A}sian strain. {I}n a gain of function approach based on the introduction of each of the nine tal genes of the avirulent {A}frican strain {MAI}1 into the virulent {A}sian strain {PXO}99({A}), four were found to trigger resistance on specific rice accessions. {L}oss-of-function mutational analysis further demonstrated the avr activity of two of them, tal{D} and tal{I}, on the rice varieties {IR}64 and {CT}13432 respectively. {F}urther analysis of {T}al{I} demonstrated the requirement of its activation domain for triggering resistance in {CT}13432. {R}esistance in 9 of the 12 rice accessions that were resistant against {A}frican {X}oo specifically, including {CT}13432, could be suppressed or largely suppressed by trans-expression of the trunc{TALE} tal2h, similarly to resistance conferred by the {X}a1 gene which recognizes {TALE}s generally independently of their activation domain. {C}onclusion {W}e identified and characterized {T}al{D} and {T}al{I} as two {A}frican {X}oo {TALE}s with avirulence activity on {IR}64 and {CT}13432 respectively. {R}esistance of {CT}13432 against {A}frican {X}oo results from the combination of two mechanisms, one relying on the {T}al{I}-mediated induction of an unknown executor gene and the other on an {X}a1-like gene or allele.},
  keywords = {{R}ice ; {B}acterial leaf blight ; trunc{TALE} ; i{TALE} ; {G}ermplasm ; {E}xecutor gene ; {X}a1-like resistance},
  booktitle = {},
  journal = {{R}ice},
  volume = {15},
  numero = {1},
  pages = {9 [13 ]},
  ISSN = {1939-8425},
  year = {2022},
  DOI = {10.1186/s12284-022-00553-9},
  URL = {https://www.documentation.ird.fr/hor/fdi:010084255},
}