KH domain protein RCF3 is a tissue-biased regulator of the plant miRNA biogenesis cofactor HYL1

Proc Natl Acad Sci U S A. 2015 Nov 10;112(45):14096-101. doi: 10.1073/pnas.1512865112. Epub 2015 Oct 28.

Abstract

The biogenesis of microRNAs (miRNAs), which regulate mRNA abundance through posttranscriptional silencing, comprises multiple well-orchestrated processing steps. We have identified the Arabidopsis thaliana K homology (KH) domain protein REGULATOR OF CBF GENE EXPRESSION 3 (RCF3) as a cofactor affecting miRNA biogenesis in specific plant tissues. MiRNA and miRNA-target levels were reduced in apex-enriched samples of rcf3 mutants, but not in other tissues. Mechanistically, RCF3 affects miRNA biogenesis through nuclear interactions with the phosphatases C-TERMINAL DOMAIN PHOSPHATASE-LIKE1 and 2 (CPL1 and CPL2). These interactions are essential to regulate the phosphorylation status, and thus the activity, of the double-stranded RNA binding protein and DICER-LIKE1 (DCL1) cofactor HYPONASTIC LEAVES1 (HYL1).

Keywords: Arabidopsis thaliana; HYL1; gene silencing; micro RNA biogenesis; phosphorylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / metabolism*
  • Base Sequence
  • DNA Primers / genetics
  • Luciferases
  • MicroRNAs / biosynthesis*
  • Molecular Sequence Data
  • RNA-Binding Proteins / metabolism*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Transgenes / genetics

Substances

  • Arabidopsis Proteins
  • DNA Primers
  • HYL1 protein, Arabidopsis
  • MicroRNAs
  • RCF3 protein, Arabidopsis
  • RNA-Binding Proteins
  • Luciferases