The chloroplastic thiol reducing systems: dual functions in the regulation of carbohydrate metabolism and regeneration of antioxidant enzymes, emphasis on the poplar redoxin equipment.
The post-translational modification consisting in the formation/reduction of disulfide bonds has been the subject of intense research in plants since the discovery in the 1970s that many chloroplastic enzymes are regulated by light through dithiol-disulfide exchange reactions catalyzed by oxidoreductases called thioredoxins (Trxs). Further biochemical and proteomic studies have considerably increased the number of target enzymes and processes regulated by these mechanisms in many sub-cellular compartments. Recently, glutathionylation, a modification consisting in the reversible formation of a glutathione adduct on cysteine residues, was proposed as an alternative redox regulation mechanism. Glutaredoxins (Grxs), proteins related to Trxs, are efficient catalysts for deglutathionylation, the opposite reaction. Hence, the Trxs- and Grxs-dependent pathways might constitute complementary and not only redundant regulatory processes. This article focuses on these two multigenic families and associated protein partners in poplar and on their involvement in the regulation of some major chloroplastic processes such as stress response, carbohydrate and heme/chlorophyll metabolism.
Chibani
Kamel
K
Unité Mixte de Recherches 1136 INRA-Nancy Université, Interactions Arbre-Microorganismes IFR 110 EFABA, Vandoeuvre-lès-Nancy Cedex, France.
Couturier
Jérémy
J
Selles
Benjamin
B
Jacquot
Jean-Pierre
JP
Rouhier
Nicolas
N
D000975:Antioxidants / Q000378:metabolism / Q000502:physiology*; D050260:Carbohydrate Metabolism / Q000502:physiology; D002736:Chloroplasts / Q000201:enzymology / Q000378:metabolism* / Q000502:physiology; D005288:Ferredoxins / Q000378:metabolism; D017343:Genes, Plant / Q000235:genetics / Q000502:physiology; D054477:Glutaredoxins / Q000378:metabolism / Q000502:physiology; D010788:Photosynthesis / Q000502:physiology; D032107:Populus / Q000201:enzymology / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D040901:Proteomics; D013312:Stress, Physiological / Q000502:physiology; D013879:Thioredoxins / Q000378:metabolism
D000975:Antioxidants; D005288:Ferredoxins; D054477:Glutaredoxins; D013879:Thioredoxins