Overexpression of thioredoxin m in tobacco chloroplasts inhibits the protein kinase STN7 and alters photosynthetic performance

Ancín, María; Millán, Alicia Fernández‐San; Larraya, Luis; Morales, Fermı́n; Veramendi, Jon; Aranjuelo, Íker; Farrán, Inmaculada

doi:10.1093/jxb/ery415

Cited by 25 publications

(15 citation statements)

References 86 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Plants of this genotype showed slower growth than the Wt and pale-green colored leaves ( Fig. 1A ), a phenotype similar to that previously reported ( Rey et al , 2013 ; Sanz-Barrio et al , 2013 ; Ancín et al , 2019 ). In the described growing conditions, o/exTrxm plants accumulated Trx m protein at levels around 12-fold higher than that of Wt plants ( Fig.…”

Section: Resultssupporting

confidence: 88%

Overexpression of thioredoxin m in chloroplasts alters carbon and nitrogen partitioning in tobacco

Ancín

Larraya

Florez‐Sarasa

et al. 2021

Journal of Experimental Botany

Self Cite

View full text Add to dashboard Cite

In plants, there is a complex interaction between carbon (C) and nitrogen (N) metabolism and its coordination is fundamental for plant growth and development. In the present work, the influence of thioredoxin (Trx) m on C and N partitioning was studied using tobacco plants overexpressing Trx m from the chloroplast genome. The transgenic plants showed altered metabolism of C (lower leaf starch and soluble sugar accumulation) and N (with higher amounts of amino acids and soluble protein), which pointed to an activation of N metabolism at the expense of carbohydrates. To further delineate the effect of Trx m overexpression, metabolomic and enzymatic analyses were performed on these plants, indicating an up-regulation of the GS-GOGAT pathway. Trx m-overexpressing plants specifically displayed increased activity and stability of glutamine synthetase in tobacco plants. Moreover, higher photorespiration and nitrate accumulation were determined in these plants relative to the untransformed control, indicating that overexpression of Trx m favors the photorespiratory N cycle rather than primary nitrate assimilation. Taken together, the combined results reveal the importance of Trx m as a molecular mediator of N metabolism in plant chloroplasts.

show abstract

Section: Resultssupporting

confidence: 88%

Overexpression of thioredoxin m in chloroplasts alters carbon and nitrogen partitioning in tobacco

Ancín

Larraya

Florez‐Sarasa

et al. 2021

Journal of Experimental Botany

Self Cite

View full text Add to dashboard Cite

show abstract

“…Proteomic and genetic approaches have revealed that chloroplast TRXs, particularly NTRC, TRXf and TRXm have several overlapping targets in photosynthetic reactions (Balmer et al ., 2003; Lindahl and Kieselbach, 2009; Okegawa and Motohashi, 2015; Thormählen et al ., 2015; Nikkanen et al ., 2018). OE‐NTRC in Arabidopsis enhanced biomass production (Toivola et al ., 2013) and OE‐TRXf in tobacco increased specific leaf weight and starch content (Sanz‐Barrio et al ., 2013), whereas OE‐TRXm impaired growth and decreased chlorophyll content in tobacco leaves (Rey et al ., 2013; Sanz‐Barrio et al ., 2013; Ancin et al ., 2018). Thus, overexpressed NTRC and TRXf have a parallel and positive role, and overexpressed TRXm an antagonist role in the regulation of photosynthesis and its productivity.…”

Section: Discussionmentioning

confidence: 99%

Two chloroplast thioredoxin systems differentially modulate photosynthesis in Arabidopsis depending on light intensity and leaf age

et al. 2020

View full text Add to dashboard Cite

Various regulatory mechanisms have evolved in plants to optimize photosynthetic activity under fluctuating light. Thioredoxins (TRX) are members of the regulatory network balancing activities of light and carbon fixation reactions in chloroplasts. We have studied the impact of two chloroplast TRX systems, the ferredoxindependent TRX reductase (FTR) and the NADPH-dependent TRX reductase C (NTRC) on regulation of photosynthesis by mutants lacking or overexpressing a component of either system. Plants were subjected to image-based phenotyping and chlorophyll fluorescence measurements that allow long-term monitoring of the development and photosynthetic activity of the rosettes, respectively. Our experiments demonstrate that NTRC and FTR systems respond differently to variation of light intensity. NTRC was an indispensable regulator of photosynthesis in young leaves, at light-intensity transitions and under low light intensities limiting photosynthesis, whereas steady-state exposure of plants to growth or higher light intensities diminished the need of NTRC in regulation of photosynthesis. In fluctuating light, overexpression of NTRC increased the quantum yield of Photosystem II (YII) at low light and stimulated the relaxation of non-photochemical quenching (NPQ) after high light exposure, indicating that overexpression of NTRC improves leaf capacity to convert light energy to chemical energy under these conditions. Overexpression of chimeric protein (NTR-TRXf) containing both the thioredoxin reductase and TRXf activity on an ntrc mutant background, did not completely recover either growth or steady-state photosynthetic activity, whereas OE-NTR-TRXf plants exposed to fluctuating light regained the wild-type level of Y(II) and NPQ.

show abstract

“…Furthermore, NTRC overexpression results in dark phosphorylation of light harvesting complex II (LHCII) proteins by the STN7 kinase and, consequently, to an increase in the relative size of the PSI antenna cross-section in dark-adapted leaves, as well as enhanced efficiency of ST [70]. In contrast, overexpression of TRXm in tobacco inhibited STN7-dependent phosphorylation of LHCII proteins and ST, while overexpression of TRXf had no effect on these processes [71]. The specific targets (single or multiple proteins) of this antagonist regulation by NTRC and TRXm remain to be elucidated in the further studies.…”

Section: Thioredoxin-dependent Regulation Of Photosynthesis and Oxidamentioning

confidence: 99%

Chloroplast thioredoxin systems dynamically regulate photosynthesis in plants

Nikkanen

Rintamäki

2019

Biochemical Journal

View full text Add to dashboard Cite

Photosynthesis is a highly regulated process in photoautotrophic cells. The main goal of the regulation is to keep the basic photosynthetic reactions, i.e. capturing light energy, conversion into chemical energy and production of carbohydrates, in balance. The rationale behind the evolution of strong regulation mechanisms is to keep photosynthesis functional under all conditions encountered by sessile plants during their lifetimes. The regulatory mechanisms may, however, also impair photosynthetic efficiency by overriding the photosynthetic reactions in controlled environments like crop fields or bioreactors, where light energy could be used for production of sugars instead of dissipation as heat and down-regulation of carbon fixation. The plant chloroplast has a high number of regulatory proteins called thioredoxins (TRX), which control the function of chloroplasts from biogenesis and assembly of chloroplast machinery to light and carbon fixation reactions as well as photoprotective mechanisms. Here, we review the current knowledge of regulation of photosynthesis by chloroplast TRXs and assess the prospect of improving plant photosynthetic efficiency by modification of chloroplast thioredoxin systems.

show abstract

Overexpression of thioredoxin m in tobacco chloroplasts inhibits the protein kinase STN7 and alters photosynthetic performance

Abstract: Plants overexpressing chloroplast Trx m, but not f, inhibited STN7 activity in a redox-dependent way, which contributes to elucidation of the specificity of chloroplast Trxs for STN7 down-regulation.

Cited by 25 publications

References 86 publications

Overexpression of thioredoxin m in chloroplasts alters carbon and nitrogen partitioning in tobacco

Overexpression of thioredoxin m in chloroplasts alters carbon and nitrogen partitioning in tobacco

Two chloroplast thioredoxin systems differentially modulate photosynthesis in Arabidopsis depending on light intensity and leaf age

Chloroplast thioredoxin systems dynamically regulate photosynthesis in plants

Contact Info

Product

Resources

About