STA1, an Arabidopsis pre-mRNA processing factor 6 homolog, is a new player involved in miRNA biogenesis

Nucleic Acids Res. 2013 Feb 1;41(3):1984-97. doi: 10.1093/nar/gks1309. Epub 2012 Dec 24.


MicroRNAs (miRNAs) are small regulatory RNAs that have important regulatory roles in numerous developmental and metabolic processes in most eukaryotes. In Arabidopsis, DICER-LIKE1 (DCL1), HYPONASTIC LEAVES 1, SERRATE, HUA ENHANCER1 and HASTY are involved in processing of primary miRNAs (pri-miRNAs) to yield precursor miRNAs (pre-miRNAs) and eventually miRNAs. In addition to these components, mRNA cap-binding proteins, CBP80/ABA HYPERSENSITIVE1 and CBP20, also participate in miRNA biogenesis. Here, we show that STABILIZED1 (STA1), an Arabidopsis pre-mRNA processing factor 6 homolog, is also involved in the biogenesis of miRNAs. Similar to other miRNA biogenesis-defective mutants, sta1-1 accumulated significantly lower levels of mature miRNAs and concurrently higher levels of pri-miRNAs than wild type. The dramatic reductions of mature miRNAs were associated with the accumulation of their target gene transcripts and developmental defects. Furthermore, sta1-1 impaired splicing of intron containing pri-miRNAs and decreased transcript levels of DCL1. These results suggest that STA1 is involved in miRNA biogenesis directly by functioning in pri-miRNA splicing and indirectly by modulating the DCL1 transcript level.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / anatomy & histology
  • Arabidopsis / genetics
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism
  • Arabidopsis Proteins / physiology*
  • Cell Cycle Proteins / genetics
  • Cell Cycle Proteins / metabolism
  • Gene Expression Regulation, Plant*
  • Genome, Plant
  • MicroRNAs / metabolism*
  • Mutation
  • Nuclear Proteins / genetics
  • Nuclear Proteins / physiology*
  • Phenotype
  • RNA Precursors / metabolism
  • RNA Splicing*
  • RNA, Messenger / metabolism
  • Ribonuclease III / genetics
  • Ribonuclease III / metabolism


  • Arabidopsis Proteins
  • Cell Cycle Proteins
  • MicroRNAs
  • Nuclear Proteins
  • RNA Precursors
  • RNA, Messenger
  • STA1 protein, Arabidopsis
  • DCL1 protein, Arabidopsis
  • Ribonuclease III