Differential expression of SlmiR-168a and SlAGO1 in JZ18 and JZ34
JZ34 tomatoes (low-K+ tolerant) show better root
development and K+ absorption ability than JZ18
tomatoes (low-K+ sensitive) under K+deficiency (Zhao et al. 2018). According to our previous miRNA-seq
research, SlmiR-168a is differentially expressed between JZ18 and
JZ34 tomatoes under K+ deficiency stress. Therefore,
in this study, we first performed RT-PCR to show that the expression
levels of SlmiR-168a were increased with time in JZ18 tomatoes
under normal conditions. However, we found that SlmiR-168a levels
were decreased under K+ deficiency with time (Fig.
1a), suggesting that in low K+-sensitive JZ18,SlmiR-168a expression affected the tolerance of tomatoes to
K+ deficiency. Corresponding expression patterns were
observed for the SlmiR-168a target gene SlAGO1 after
treatment for 3 and 5 days (Fig. 1b). However, in JZ34 tomatoes, the
expression levels of SlmiR-168a were significantly increased by
K+ deficiency, particularly after treatment for 3, 5,
and 7 days (Fig. 1c). The target AGO1 expression levels were obviously
decreased under K+ deficiency compared with that under
normal conditions in JZ34 tomatoes (Fig. 1d). As a target ofmiR-168a , SlAGO1 showed a complementary expression
pattern, and the expression of SlmiR-168a actually responded to
the low K+ stress. The differential expression
patterns of SlmiR-168a between JZ18 and JZ34 tomatoes may be a
cause of the variations in tolerance of the two tomato genotypes under
low K+ stress.