Animal and plant mitochondria contain specific thioredoxins

Bodenstein-Lang, Johanna; Buch, Angela M; Follmann, Hartmut

doi:10.1016/0014-5793(89)81606-0

Cited by 73 publications

(23 citation statements)

References 32 publications

(21 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is consistent with AOX reduction being mediated by a thioredoxin-or glutaredoxin-based enzyme system, both of which use NADPH (Holmgren, 1989). Components of each of these systems have been identified in plant mitochondria, but, as yet, potential specific function(s) have not been identified (Bodenstein-Lang et al, 1989;Rasmusson and Maller, 1990). It is interesting that reduced thioredoxin from Esckerickiu coli can reduce soybean AOX in insideout submitochondrial particles (J.N.…”

Section: +Aamentioning

confidence: 57%

Alternative Oxidase Activity in Tobacco Leaf Mitochondria (Dependence on Tricarboxylic Acid Cycle-Mediated Redox Regulation and Pyruvate Activation)

et al. 1995

View full text Add to dashboard Cite

Transgenic Nicofiana tabacum (cv Petit Havana SR1) containing high levels of mitochondrial alternative oxidase (AOX) protein due t o the introduction of a sense transgene(s) of Aoxl, the nuclear gene encoding AOX, were used t o investigate mechanisms regulating AOX activity. After purification of leaf mitochondria, a large proportion of the AOX protein was present as the oxidized (covalently associated and less active) dimer. High AOX activity in these mitochondria was dependent on both reduction of the protein by DTT (to the noncovalently associated and more active dimer) and its subsequent activation by certain a-keto acids, particularly pyruvate. Reduction of AOX t o its more active form could also be mediated by intramitochondrial reducing power generated by the oxidation of certain tricarboxylic acid cycle substrates, most notably isocitrate and malate. Our evidence suggests that NADPH may be specifically required for AOX reduction. All of the above regulatory mechanisms applied to AOX in wild-type mitochondria as well. Transgenic leaves lacking AOX due t o the introduction of an Aoxl antisense transgene or multiple sense transgenes were used to investigate the potential physiological significance of the AOXregulatory mechanisms. Under conditions in which respiratory carbon metabolism is restricted by the capacity of mitochondrial electron transport, feed-forward activation of AOX by mitochondrial reducing power and pyruvate may act t o prevent redirection of carbon metabolism, such as to fermentative pathways.

show abstract

Section: +Aamentioning

confidence: 57%

Alternative Oxidase Activity in Tobacco Leaf Mitochondria (Dependence on Tricarboxylic Acid Cycle-Mediated Redox Regulation and Pyruvate Activation)

et al. 1995

View full text Add to dashboard Cite

show abstract

“…On the other hand, the reaction is of major interest in connection with the existence of specific mitochondrial thioredoxins [5,6]. We suggest that a-ketoaciddependent thioredoxin reduction is an integral part of the thioredoxin cycle in mitochondria.…”

Section: Discussionmentioning

confidence: 99%

“…It has been prompted by our earlier observation of specific mitochondrial thioredoxins [5,6], which are in search of a function.…”

Section: Introductionmentioning

confidence: 99%

Thioredoxin reduction dependent on α‐ketoacid oxidation by α‐ketoacid dehydrogenase complexes

Bunik¹,

Follmann²

1993

FEBS Letters

Self Cite

View full text Add to dashboard Cite

The pyruvate and a-ketoglutarate dehydrogenase complexes isolated from pig heart mitochondria promote the reduction of thioredoxin in the presence of their a-ketoacid substrates, coenzyme A, and free lipoate. Substrate-specific generation of reduced thioredoxin was established by two independent methods, viz. reduction of insulin and thioredoxin reductase-catalyzed NADPH formation. Dihydrolipoate accumulating in the absence of NAD' is the likely intermediate. A redox function in a-ketoacid oxidation provides a potential role for the specific thioredoxins previously identified by us in mitochondria.

show abstract

“…Early reports indicated that plant mitochondria also contain at least one thioredoxin (12,92), but no cDNA sequence has been unambiguously shown to code for a transit peptide that targets the mitochondrial compartment. Similarly, no plant mitochondrial NTR sequence has yet been isolated.…”

Section: Thioredoxin Systems In Mitochondriamentioning

confidence: 99%

Plant Thioredoxin Systems Revisited

Schürmann

Jacquot

2000

Annu. Rev. Plant. Physiol. Plant. Mol. Biol.

376

267

View full text Add to dashboard Cite

s Abstract Thioredoxins, the ubiquitous small proteins with a redox active disulfide bridge, are important regulatory elements in plant metabolism. Initially recognized as regulatory proteins in the reversible light activation of key photosynthetic enzymes, they have subsequently been found in the cytoplasm and in mitochondria. The various plant thioredoxins are different in structure and function. Depending on their intracellular location they are reduced enzymatically by an NADP-dependent or by a ferredoxin (light)-dependent reductase and transmit the regulatory signal to selected target enzymes through disulfide/dithiol interchange reactions. In this review we summarize recent developments that have provided new insights into the structures of several components and into the mechanism of action of the thioredoxin systems in plants.

show abstract

Animal and plant mitochondria contain specific thioredoxins

Cited by 73 publications

References 32 publications

Alternative Oxidase Activity in Tobacco Leaf Mitochondria (Dependence on Tricarboxylic Acid Cycle-Mediated Redox Regulation and Pyruvate Activation)

Alternative Oxidase Activity in Tobacco Leaf Mitochondria (Dependence on Tricarboxylic Acid Cycle-Mediated Redox Regulation and Pyruvate Activation)

Thioredoxin reduction dependent on α‐ketoacid oxidation by α‐ketoacid dehydrogenase complexes

Plant Thioredoxin Systems Revisited

Contact Info

Product

Resources

About