MicroRNAs and other small RNAs enriched in the Arabidopsis RNA-dependent RNA polymerase-2 mutant.

摘要: The Arabidopsis genome contains a highly complex and abundant population of small RNAs, many the endogenous siRNAs are dependent on RNA-Dependent RNA Polymerase 2 (RDR2) for their biogenesis. By analyzing an rdr2 loss-of-function mutant using two different parallel sequencing technologies, MPSS 454, we characterized complement miRNAs expressed in inflorescence to considerable depth. Nearly all known were enriched this identified 13 new miRNAs, which relatively low abundance constitute families. Trans-acting (ta-siRNAs) even more enriched. Computational gel blot analyses suggested that minimal number is approximately 155. size profile RNAs reflected enrichment 21-nt other classes like ta-siRNAs, significant reduction 24-nt heterochromatic siRNAs. Other found be RDR2-independent, particularly those derived from long inverted repeats subset tandem repeats. populations biogenesis mutants also examined; dcl2/3/4 triple showed similar pattern rdr2, whereas dcl1-7 rdr6 reductions ta-siRNAs consistent with activities these types RNAs. Deep provides genetic approach dissection characterization diverse identification miRNAs.