The Arabidopsis homologue of Pha13, AtSAP5, is induced by SA and involved in virus resistance.

(A) The expression of AtSAP5 were analyzed by qRT-PCR in the WT, AtSAP5 overexpression lines (AtSAP5-oe-4 and AtSAP5-oe-11), and RNAi lines (AtSAP5-RNAi-3 and AtSAP5-RNAi-7). Data represent mean ± SD; n = 3 biological replicates *, p<0.05, Student’s t-test compared to WT (B) The accumulation levels of Cucumber mosaic virus (CMV) were analyzed by qRT-PCR from leaves of WT inoculated with buffer (Mock), CMV-inoculated WT, or CMV-inoculated transgenic Arabidopsis. Data represent mean ± SD; n = 5 biological replicates *, p<0.05, Student’s t-test compared to WT (C) Disease symptoms of CMV inoculated WT or transgenic Arabidopsis. The experiments were repeated twice with similar results, and 5 plants were used in each inoculation. Photo of one representative plant from each inoculation taken at 9 days post inoculation are shown here; Scale bar, 1 cm. (D) Time-course expression of AtSAP5 in SA-treated wild-type (WT, Col-0) Arabidopsis. Expression level of AtSAP5 was analyzed by qRT-PCR from leaves at 1 and 6 h post-treatment. Water treatment was used as a mock control. Data represent mean ± SD; n = 3 biological replicates *, p<0.05, Student’s t-test compared to mock. Actin was used as an internal control for normalization.