Fig. 2.

PINP1 plays a role in small RNA accumulation in Arabidopsis. (A) Silencing of PINP1 leads to developmental defects. Photos of wild-type (Col-0) and three independent PINP1-silenced lines (PINP1i-7, PINP1i-10, and PINP1i-28) were taken after 4 wk (Left) and 8 wk (Right) of growth. (B) Transcript abundances of PINP1 in the silenced lines compared with wild-type (Col-0) were determined by qRT-PCR. AtUBQ10 was used as the internal standard. Values are means ± SDs (as error bars) from three independent replicates. Letters represent differences with statistical significance (P < 0.01) as determined by Duncan’s multiple test. (C) Northern blots showing endogenous small RNA abundances in PINP1-silenced plants and the PSR1 transgenic line PSR1-19. Results from four representative miRNAs, two ta-siRNAs (ASRP255 and ASRP1151), and two heterochromatic siRNAs (Si1003 and AtSN1) are presented. U6 serves as the loading control. Numbers below each blot indicate relative abundances of the small RNA. Data from additional miRNAs and siRNAs are shown in Fig. S2A. These experiments were repeated twice with similar results.