SRP006214 PRJNA138567 GSE27517 Analysis of small RNA population in Arabidopsis drb2 and drb4 mutants We have compared populations of small (21 to 24-nt) RNAs from Arabidopsis immature flowers of WT, drb2 and drb4 mutants and found that DRB2 and DRB4 are needed for the proper biogenesis of polymerase IV-dependent siRNAs Overall design: Examination of small RNA populations from three backgournd: Col0 (WT), drb2 and drb4 mutants GSE27517 pubmed 21700726