Analysis of RDR6-dependent endogenous ta-siRNAs content in dcl mutants. RNA gel blots analysis of 10 μg total RNA prepared from inflorescence of wild-type Col, and dcl1, dcl3 dcl4, dcl2 dcl3 dcl4, dcl1 dcl2 dcl3 dcl4 mutants. The blots were probed with DNAs complementary to ta-siRNAs, miRNAs and U6, which served as a loading control.