TY - JOUR

T1 - Analysis of oligomeric protein complexes in the chloroplast sub-proteome of nucleic acid-binding proteins from mustard reveals potential redox regulators of plastid gene expression

AU - Schröter, Yvonne

AU - Steiner, Sebastian

AU - Matthäi, Kevin

AU - Pfannschmidt, Thomas

PY - 2010/6

Y1 - 2010/6

N2 - Photosynthetic light quality acclimation in plants involves redox-controlled changes in plastid gene expression. To study proteins potentially involved in this regulation, we isolated low-abundant chloroplast nucleic acid-binding proteins from the crucifere mustard (Sinapis alba) and investigated if photosynthetic redox signals affect their composition and/or oligomeric structure. We purified chloroplasts from plants subjected to light quality shifts and applied organelle lysates to heparin-Sepharose chromatography followed by 2-D blue native PAGE. We studied accumulation and structure of oligomeric protein complexes and applied MS/MS to identify them. We found ten oligomeric protein complexes of higher order and eleven smaller protein complexes or spots including plastid-encoded RNA polymerase (PEP), plastid transcriptionally active chromosome proteins, RNA-binding proteins, ribosomal subunits and chaperones. A translation elongation factor was found to be the only protein displaying major differences in its amounts in response to the growth lights. Furthermore, we found a novel thioredoxin as a subunit of the PEP, a 2-Cys-peroxiredoxin complex and a (soluble) ferredoxin:NADP-oxido-reductase, which represent potential redox regulator of plastid gene expression. A T-DNA knock-out line of the thioredoxin from Arabidopsis exhibits a yellowish-pale phenotype, demonstrating that this novel PEP subunit is essential for proper plastid development.

AB - Photosynthetic light quality acclimation in plants involves redox-controlled changes in plastid gene expression. To study proteins potentially involved in this regulation, we isolated low-abundant chloroplast nucleic acid-binding proteins from the crucifere mustard (Sinapis alba) and investigated if photosynthetic redox signals affect their composition and/or oligomeric structure. We purified chloroplasts from plants subjected to light quality shifts and applied organelle lysates to heparin-Sepharose chromatography followed by 2-D blue native PAGE. We studied accumulation and structure of oligomeric protein complexes and applied MS/MS to identify them. We found ten oligomeric protein complexes of higher order and eleven smaller protein complexes or spots including plastid-encoded RNA polymerase (PEP), plastid transcriptionally active chromosome proteins, RNA-binding proteins, ribosomal subunits and chaperones. A translation elongation factor was found to be the only protein displaying major differences in its amounts in response to the growth lights. Furthermore, we found a novel thioredoxin as a subunit of the PEP, a 2-Cys-peroxiredoxin complex and a (soluble) ferredoxin:NADP-oxido-reductase, which represent potential redox regulator of plastid gene expression. A T-DNA knock-out line of the thioredoxin from Arabidopsis exhibits a yellowish-pale phenotype, demonstrating that this novel PEP subunit is essential for proper plastid development.

KW - Blotting, Western

KW - DNA-Binding Proteins/metabolism

KW - Mustard Plant/metabolism

KW - Oxidation-Reduction

KW - Plant Proteins/metabolism

KW - Plastids/metabolism

KW - Tandem Mass Spectrometry

U2 - 10.1002/pmic.200900678

DO - 10.1002/pmic.200900678

M3 - Article

C2 - 20340159

VL - 10

SP - 2191

EP - 2204

JO - PROTEOMICS

JF - PROTEOMICS

SN - 1615-9853

IS - 11

ER -