Journal Article

The Active Site of the Thioredoxin-Like Domain of Chloroplast Protein Disulfide Isomerase, RB60, Catalyzes the Redox-Regulated Binding of Chloroplast Poly(A)-Binding Protein, RB47, to the 5′ Untranslated Region of <i>psbA</i> mRNA

Jungmook Kim and Stephen P. Mayfield

in Plant and Cell Physiology

Published on behalf of Japanese Society of Plant Physiologists

Volume 43, issue 10, pages 1238-1243
Published in print October 2002 | ISSN: 0032-0781
Published online October 2002 | e-ISSN: 1471-9053 | DOI: http://dx.doi.org/10.1093/pcp/pcf129
The Active Site of the Thioredoxin-Like Domain of Chloroplast Protein Disulfide Isomerase, RB60, Catalyzes the Redox-Regulated Binding of Chloroplast Poly(A)-Binding Protein, RB47, to the 5′ Untranslated Region of psbA mRNA

More Like This

Show all results sharing these subjects:

  • Biochemistry
  • Molecular and Cell Biology
  • Plant Sciences and Forestry

GO

Show Summary Details

Preview

RB60, a chloroplast protein disulfide isomerase, modulates the binding of RB47, chloroplast poly(A)-binding protein, to the 5′-UTR of the psbA mRNA using redox potential, allowing for a reversible switch capable of regulating psbA mRNA translation in a light/dark dependent manner. RB60 contains two thioredoxin-like domains with putative catalytic sites of -Cys-Gly-His-Cys- that are presumed to function as active sites for the redox-regulated changes in RNA-binding activity of RB47. To investigate whether these motifs are required for redox-regulated RNA binding, RNA-gel-mobility shift assays were performed with RB47 and mutant RB60 proteins with single cysteines changed to serines in the -Cys-Gly-His-Cys- motif. The results showed that each thioredoxin-like domain has independent catalytic function in the reactivation of RB47 binding and that a double active site mutant completely lacks the ability to activate RB47 RNA binding activity.

Keywords: Keywords: psbA mRNA translation — Poly(A)-binding protein — Protein disulfide isomerase — Thioredoxin-like domain — Redox.; Abbreviations: cPABP, chloroplast poly(A)-binding protein; cPDI, chloroplast protein disulfide isomerase; DTNB, 5,5′-dithiobis(2-nitrobenzoic acid); DTT, dithiothreitol; ER, endoplasmic reticulum; RRM, RNA recognition motif; UTR, untranslated region.

Journal Article.  3210 words.  Illustrated.

Subjects: Biochemistry ; Molecular and Cell Biology ; Plant Sciences and Forestry

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.