Open AccessCross‐protection in Arabidopsis against crucifer tobamovirus Cg by an attenuated strain of the virus
Author(s) -
Kurihara Yukio,
Watanabe Yuichiro
Publication year - 2003
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1046/j.1364-3703.2003.00174.x
Subject(s) - tobamovirus , biology , arabidopsis , virology , mutant , rna silencing , rna , arabidopsis thaliana , crucifer , tobacco mosaic virus , virus , rna dependent rna polymerase , gene , genetics , rna interference , botany
SUMMARY Cross‐protection is a procedure that has been utilized to protect crops against virulent strains of viruses by pre‐treatment with closely related attenuated strains of the virus. We constructed a mutant of crucifer tobamovirus Cg, which is analogous to L 11 A, an attenuated strain of Tomato mosaic virus ‐L (ToMV‐L). This mutant, named CgYD, caused few disease symptoms and could spread throughout Arabidopsis thaliana Col‐0 plants. Initial infection with CgYD was shown to efficiently cross‐protect against a challenge with wild‐type Cg. Thus, we have established in Arabidopsis a powerful system for investigating mechanisms of cross‐protection. Using this system, we showed that cross‐protection was not overcome, even if a higher concentration of the virion, or purified virion RNA, were used in the challenge. We also demonstrated that cross‐protection requires that the second virus be very similar in sequence to Cg, which is a characteristic of RNA silencing. However the RNA dependent RNA polymerase SDE1/SGS2 associated with post‐transcriptional gene silencing was not required for cross‐protection.