Regulation of small RNA accumulation in the maize shoot apex.

ABSTRACT: MicroRNAs (miRNAs) and trans-acting siRNAs (ta-siRNAs) are essential to the establishment of adaxial-abaxial (dorsoventral) leaf polarity. Tas3-derived ta-siRNAs define the adaxial side of the leaf by restricting the expression domain of miRNA miR166, which in turn demarcates the abaxial side of leaves by restricting the expression of adaxial determinants. To investigate the regulatory mechanisms that allow for the precise spatiotemporal accumulation of these polarizing small RNAs, we used laser-microdissection coupled to RT-PCR to determine the expression profiles of their precursor transcripts within the maize shoot apex. Our data reveal that the pattern of mature miR166 accumulation results, in part, from intricate transcriptional regulation of its precursor loci and that only a subset

SUBMITTER: Nogueira FT 

PROVIDER: S-EPMC2602737 | biostudies-literature | 2009 Jan

REPOSITORIES: biostudies-literature