Is AKR2A an essential molecular chaperone for a class of membrane-bound proteins in plants?

Hong Zhang, Xiao Li, Yizheng Zhang, Sundaram Kuppu, Guoxin Shen

Research output: Contribution to journalArticle

9 Scopus citations


The Arabidopsis ankyrin-repeat containing protein 2A (AKR2A) was shown to be an essential molecular chaperone for the peroxisomal membranebound ascorbate peroxidase 3 (APX3), because the biogenesis of APX3 depends on the function of AKR2A in plant cells. AKR2A binds specifically to a sequence in APX3 that is made up of a transmembrane domain followed by a few positively charged amino acid residues; this sequence is named as AKR2Abinding sequence or ABS. Interestingly, a sequence in the chloroplast outer envelope protein 7 (OEP7) shares similar features to ABS and is able to bind specifically to AKR2A, suggesting a possibility that proteins with a sequence similar to ABS could bind to AKR2A and they are all likely ligand proteins of AKR2A. This hypothesis was supported by analyzing 5 additional proteins that contain sequences similar to ABS using the yeast two-hybrid technique. A preliminary survey in the Arabidopsis genome indicates that there are at least 500 genes encoding proteins that contain sequences similar to ABS, which raises interesting questions: Are these proteins AKR2A's ligand proteins and does AKR2A play a critical role in the biogenesis of these proteins in plants?

Original languageEnglish
JournalPlant Signaling and Behavior
Issue number11
StatePublished - Nov 2010



  • Arabidopsis
  • Membrane protein
  • Molecular chaperone
  • Protein targeting
  • Transmembrane domain

Cite this