Dosage effect of the TBSV-encoded P19 RNA silencing suppressor on transient expression of the GUS reporter gene in sugarcane protoplasts.

DNA (5 µg) from pUbi:GUS:Tnos (Figure S3) was co-transfected into a protoplast suspension (100 µL; 1×105 protoplasts) with three concentrations of P19 DNA (pUbi:P19:Tnos) (Figure S3), respectively, and GUS activity of protoplasts was measured at 24 h post-transfection. Vector with no P19 suppressor (pUbi:Tnos; Figure S3) and sterile water were used as controls. Values represent three biological samples and six technical repeats, and are reported with the standard error. Means with the same letter are not significantly different (p>0.05).