TY - JOUR
T1 - An effector from the Huanglongbing-associated pathogen targets citrus proteases
AU - Clark, Kelley
AU - Franco, Jessica Yvette
AU - Schwizer, Simon
AU - Pang, Zhiqian
AU - Hawara, Eva
AU - Liebrand, Thomas W. H.
AU - Pagliaccia, Deborah
AU - Zeng, Liping
AU - Gurung, Fatta B.
AU - Wang, Pengcheng
AU - Shi, Jinxia
AU - Wang, Yinsheng
AU - Ancona, Veronica
AU - Van Der Hoorn, Renier A. L.
AU - Wang, Nian
AU - Coaker, Gitta
AU - Ma, Wenbo
PY - 2018/12/1
Y1 - 2018/12/1
N2 - The citrus industry is facing an unprecedented challenge from Huanglongbing (HLB). All cultivars can be affected by the HLB-associated bacterium ‘Candidatus Liberibacter asiaticus’ (CLas) and there is no known resistance. Insight into HLB pathogenesis is urgently needed in order to develop effective management strategies. Here, we use Sec-delivered effector 1 (SDE1), which is conserved in all CLas isolates, as a molecular probe to understand CLas virulence. We show that SDE1 directly interacts with citrus papain-like cysteine proteases (PLCPs) and inhibits protease activity. PLCPs are defense-inducible and exhibit increased protein accumulation in CLas-infected trees, suggesting a role in citrus defense responses. We analyzed PLCP activity in field samples, revealing specific members that increase in abundance but remain unchanged in activity during infection. SDE1-expressing transgenic citrus also exhibit reduced PLCP activity. These data demonstrate that SDE1 inhibits citrus PLCPs, which are immune-related proteases that enhance defense responses in plants.
AB - The citrus industry is facing an unprecedented challenge from Huanglongbing (HLB). All cultivars can be affected by the HLB-associated bacterium ‘Candidatus Liberibacter asiaticus’ (CLas) and there is no known resistance. Insight into HLB pathogenesis is urgently needed in order to develop effective management strategies. Here, we use Sec-delivered effector 1 (SDE1), which is conserved in all CLas isolates, as a molecular probe to understand CLas virulence. We show that SDE1 directly interacts with citrus papain-like cysteine proteases (PLCPs) and inhibits protease activity. PLCPs are defense-inducible and exhibit increased protein accumulation in CLas-infected trees, suggesting a role in citrus defense responses. We analyzed PLCP activity in field samples, revealing specific members that increase in abundance but remain unchanged in activity during infection. SDE1-expressing transgenic citrus also exhibit reduced PLCP activity. These data demonstrate that SDE1 inhibits citrus PLCPs, which are immune-related proteases that enhance defense responses in plants.
U2 - 10.1038/s41467-018-04140-9
DO - 10.1038/s41467-018-04140-9
M3 - Article
VL - 9
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
IS - 1
M1 - 1718
ER -
