Expression analysis of miRNAs in different tissues and different development stages of tuberization in potato by qRT-PCR. A) The expression profile of 15 conserved miRNA identified in this study in potato (miR164_1, miR172_1, miR394_1, miR396_1, miR399_1, miR171_2, miR159_1, miR157_1, miR172_5, miR171_9, miR6149_1, miR482_1, miR171_10, miR398_1, miR8044_1). B) The expression profile of 6 potato-specific miRNAs identified in this study (miRNA72, miRNA111, miRNA53, miRNA193, miRNA34, miRNA152). The expression level of each miRNA in PT0 was set as control and taken as 1, and expression level in all other tissues was quantified relative to it. 18S rRNA was taken as an endogenous control. L - Leaf, S - Stem, R - Root, PT0 - 0 stage of tuberization, PT1 - 1st stage of tuberization, PT2 - 2nd stage of tuberization, PT3 - 3rd stage of tuberization (for details of the tuberization stages see Figure 1).