SVP-like MADS-box protein from Carya cathayensis forms higher-order complexes

Plant Physiol Biochem. 2015 Mar:88:9-16. doi: 10.1016/j.plaphy.2015.01.002. Epub 2015 Jan 7.

Abstract

To properly regulate plant flowering time and construct floral pattern, MADS-domain containing transcription factors must form multimers including homo- and hetero-dimers. They are also active in forming hetero-higher-order complexes with three to five different molecules. However, it is not well known if a MADS-box protein can also form homo-higher-order complex. In this study a biochemical approach is utilized to provide insight into the complex formation for an SVP-like MADS-box protein cloned from hickory. The results indicated that the protein is a heterogeneous higher-order complex with the peak population containing over 20 monomers. Y2H verified the protein to form homo-complex in yeast cells. Western blot of the hickory floral bud sample revealed that the protein exists in higher-order polymers in native. Deletion assays indicated that the flexible C-terminal residues are mainly responsible for the higher-order polymer formation and the heterogeneity. Current results provide direct biochemical evidences for an active MADS-box protein to be a high order complex, much higher than a quartermeric polymer. Analysis suggests that a MADS-box subset may be able to self-assemble into large complexes, and thereby differentiate one subfamily from the other in a higher-order structural manner. Present result is a valuable supplement to the action of mechanism for MADS-box proteins in plant development.

Keywords: MADS-box transcription factor; Multimer; Plant flowering; Protein interaction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Carya / genetics*
  • Carya / growth & development
  • Carya / metabolism
  • Flowers / growth & development*
  • Flowers / metabolism
  • Gene Expression Regulation, Plant*
  • MADS Domain Proteins / metabolism*
  • Molecular Sequence Data
  • Phylogeny
  • Plant Development
  • Plant Proteins / metabolism*
  • Sequence Alignment
  • Transcription Factors / metabolism*
  • Two-Hybrid System Techniques
  • Yeasts

Substances

  • MADS Domain Proteins
  • Plant Proteins
  • Transcription Factors