TY  - JOUR
A1  - Wimmelbacher, Matthias
A1  - Börnke, Frederik
T1  - Redox activity of thioredoxin z and fructokinase-like protein 1 is dispensable for autotrophic growth of Arabidopsis thaliana
T2  - Journal of experimental botany
N2  - Redox modulation of protein activity by thioredoxins (TRXs) plays a key role in cellular regulation. Thioredoxin z (TRX z) and its interaction partner fructokinase-like protein 1 (FLN1) represent subunits of the plastid-encoded RNA polymerase (PEP), suggesting a role of both proteins in redox regulation of chloroplast gene expression. Loss of TRX z or FLN1 expression generates a PEP-deficient phenotype and renders the plants incapable to grow autotrophically. This study shows that PEP function in trx z and fln1 plants can be restored by complementation with redox-inactive TRX z C106S and FLN1 C(105/106)A protein variants, respectively. The complemented plants showed wild-type levels of chloroplast gene expression and were restored in photosynthetic capacity, indicating that redox regulation of PEP through TRX z/FLN1 per se is not essential for autotrophic growth. Promoter-reporter gene studies indicate that TRX z and FLN1 are expressed during early phases of leaf development while expression ceases at maturation. Taken together, our data support a model in which TRX z and FLN1 are essential structural components of the PEP complex and their redox activity might only play a role in the fine tuning of PEP function.
KW  - Chloroplast transcription
KW  - FLN1
KW  - plastid-encoded RNA polymerase
KW  - redox regulation
KW  - thioredoxins
KW  - TRX z
Y1  - 2014
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/37801
SN  - 0022-0957
SN  - 1460-2431
VL  - 65
IS  - 9
SP  - 2405
EP  - 2413
PB  - Oxford Univ. Press
CY  - Oxford
ER  -