Two splice variants of the IDD14 transcription factor competitively form nonfunctional heterodimers which may regulate starch metabolism

Nat Commun. 2011;2:303. doi: 10.1038/ncomms1303.

Abstract

Alternative splicing of primary gene transcripts provides eukaryotic cells, with a critical scheme for enriching transcriptome and proteome diversity. Here we report that alternative splicing of the Arabidopsis INDERMINATE DOMAIN 14 (IDD14) transcription factor gene generates a competitive inhibitor in regulating starch metabolism. An alternatively spliced IDD14 form (IDD14β), which is produced predominantly under cold conditions, lacks functional DNA-binding domain but is able to form heterodimers with the functional IDD14 form (IDD14α). IDD14α-IDD14β heterodimers have reduced binding activity to the promoter of Qua-Quine Starch (QQS) gene that regulates starch accumulation. Transgenic Arabidopsis plants overproducing IDD14α (35S:IDD14α) exhibited retarded growth with pale green leaves as appeared on QQS-overexpressing plants. Notably, IDD14β overproduction rescued the 35S:IDD14α phenotypes. We propose that alternative splicing of the IDD14 gene generates a self-controlled regulatory loop that may modulate starch accumulation in response to cold.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alternative Splicing / genetics*
  • Arabidopsis / genetics
  • Arabidopsis / growth & development
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Cold Temperature
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Plant
  • Genetic Variation
  • Plant Leaves / genetics
  • Plant Leaves / growth & development
  • Plant Leaves / metabolism
  • Plants, Genetically Modified / genetics
  • Plants, Genetically Modified / metabolism
  • Protein Multimerization*
  • Proteome / genetics
  • Proteome / metabolism
  • Starch / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Arabidopsis Proteins
  • DNA-Binding Proteins
  • Proteome
  • Transcription Factors
  • indeterminate(ID)-domain 14 protein, Arabidopsis
  • Starch