Alternative respiratory pathway in ripening fruits

2015 ◽  
pp. 201-219 ◽  
Author(s):  
Bhagyalakshmi Neelwarne
Keyword(s):  
Respiratory Pathway ◽  
Alternative Respiratory Pathway

Cloning and Analysis of the Alternative Oxidase Gene of Neurospora crassa

Genetics ◽  
1996 ◽  
Vol 142 (1) ◽  
pp. 129-140 ◽  
Author(s):  
Qiuhong Li ◽  
R Gary Ritzel ◽  
Lesley L T McLean ◽  
Lee McIntosh ◽  
Tak Ko ◽  
...  
Keyword(s):  
Neurospora Crassa ◽  
Alternative Oxidase ◽  
Electron Flow ◽  
Mitochondrial Protein ◽  
Transcriptional Level ◽  
Wild Type ◽  
Respiratory Pathway ◽  
Oxidase Gene ◽  
Alternative Respiratory Pathway ◽  
Cytochrome Pathway

Mitochondria of Neurospora crassa contain a cyanide-resistant alternative respiratory pathway in addition to the cytochrome pathway. The alternative oxidase is present only when electron flow through the cytochrome chain is restricted. Both genomic and cDNA copies for the alternative oxidase gene have been isolated and analyzed. The sequence of the predicted protein is homologous to that of other species. The mRNA for the alternative oxidase is scarce in wild-type cultures grown under normal conditions, but it is abundant in cultures grown in the presence of chloramphenicol, an inhibitor of mitochondrial protein synthesis, or in mutants deficient in mitochondrial cytochromes. Thus, induction of alternative oxidase appears to be at the transcriptional level. Restriction fragment length polymorphism mapping of the isolated gene demonstrated that it is located in a position corresponding to the aod-1 locus. Sequence analysis of mutant aod-1 alleles reveals mutations affecting the coding sequence of the alternative oxidase. The level of aod-1 mRNA in an aod-2 mutant strain that had been grown in the presence of chloramphenicol was reduced several fold relative to wild-type, supporting the hypothesis that the product of aod-2 is required for optimal expression of aod-1.

Arabidopsis mtHSC70-1 plays important roles in the establishment of COX-dependent respiration and redox homeostasis

2019 ◽  
Vol 70 (20) ◽  
pp. 5575-5590 ◽  
Author(s):  
Shan-Shan Wei ◽  
Wei-Tao Niu ◽  
Xiao-Ting Zhai ◽  
Wei-Qian Liang ◽  
Meng Xu ◽  
...  
Keyword(s):  
Alternative Oxidase ◽  
Redox Homeostasis ◽  
Superoxide Dismutase 1 ◽  
Respiratory Pathway ◽  
Cellular Processes ◽  
Growth Defects ◽  
Alternative Respiratory Pathway ◽  
Abnormal Mitochondria ◽  
Shock Proteins ◽  
Severe Growth

Abstract The 70 kDa heat shock proteins function as molecular chaperones and are involved in diverse cellular processes. However, the functions of the plant mitochondrial HSP70s (mtHSC70s) remain unclear. Severe growth defects were observed in the Arabidopsis thaliana mtHSC70-1 knockout lines, mthsc70-1a and mthsc70-1b. Conversely, the introduction of the mtHSC70-1 gene into the mthsc70-1a background fully reversed the phenotypes, indicating that mtHSC70-1 is essential for plant growth. The loss of mtHSC70-1 functions resulted in abnormal mitochondria and alterations to respiration because of an inhibition of the cytochrome c oxidase (COX) pathway and the activation of the alternative respiratory pathway. Defects in COX assembly were observed in the mtHSC70-1 knockout lines, leading to decreased COX activity. The mtHSC70-1 knockout plants have increased levels of reactive oxygen species (ROS). The introduction of the Mn-superoxide dismutase 1 (MSD1) or the catalase 1 (CAT1) gene into the mthsc70-1a plants decreased ROS levels, reduced the expression of alternative oxidase, and partially rescued growth. Taken together, our data suggest that mtHSC70-1 plays important roles in the establishment of COX-dependent respiration.

The Role of Cu in Respiration of Pea Plants and Heterotrophically Growing Scenedesmus Cells

1988 ◽  
Vol 43 (5-6) ◽  
pp. 438-442 ◽  
Author(s):  
Matilde Barón Ayala ◽  
Gerhard Sandmann
Keyword(s):  
Cytochrome Oxidase ◽  
Respiratory Activity ◽  
The Other ◽  
Nadh Oxidation ◽  
Alternative Respiration ◽  
Respiratory Pathway ◽  
Cu Deficiency ◽  
Alternative Respiratory Pathway

In Scenedesmus about half of NADH oxidation proceeds via a cyanide-sensitive and the other half via a cyanide-insensitive respiratory pathway. In contrast, respiration is completely cyanide sensitive in pea indicating that the alternative respiratory pathway is absent. Cu deficiency in pea plants and in heterotrophically grown Scenedesmus cells interferes with respiratory activity of mitochondria. In both organisms, the cyanide-sensitive NADH oxidation was strongly decreased during cultivation in low Cu media. Cu sensitivity was also observed for the alternative respiratory pathway in Scenedesmus. These results suggest that a Cu-containing component is involved in the alternative respiratory pathway. This is the main reason why alternative respiration cannot be regarded as a compensation for low cytochrome-oxidase activities during Cu starvation. The Cu dependency of the cyanide-sensitive respiration was located at the site of cytochrome oxidase. A strong coordination of the biosynthesis of the Cu-containing cytochrome-oxidase complex was evident. When the endogenous Cu pool was low, formation of cytochrome aa3, another component of cytochrome oxidase, was also decreased.

scholarly journals Alternative Respiratory Pathway

1980 ◽  
Vol 65 (4) ◽  
pp. 669-674 ◽  
Author(s):  
James N. Siedow ◽  
Mark E. Girvin
Keyword(s):  
Respiratory Pathway ◽  
Alternative Respiratory Pathway

Effect of 24-epibrassinolide on Arabidopsis thaliana alternative respiratory pathway under salt stress

2015 ◽  
Vol 37 (10) ◽  
Author(s):  
Michael Derevyanchuk ◽  
Raisa Litvinovskaya ◽  
Vladimir Khripach ◽  
Jan Martinec ◽  
Volodymyr Kravets
Keyword(s):  
Arabidopsis Thaliana ◽  
Salt Stress ◽  
Respiratory Pathway ◽  
Alternative Respiratory Pathway

Functional analysis reveals effects of tobacco alternative oxidase gene (NtAOX1a) on regulation of defence responses against abiotic and biotic stresses

2009 ◽  
Vol 29 (6) ◽  
pp. 375-383 ◽  
Author(s):  
Yi Zhang ◽  
Dongmei Xi ◽  
Jian Wang ◽  
Dongfang Zhu ◽  
Xingqi Guo
Keyword(s):  
Oxidative Stress ◽  
Low Temperature ◽  
Alternative Oxidase ◽  
Alternative Pathway ◽  
Respiratory Pathway ◽  
Oxidase Gene ◽  
Biotic Stresses ◽  
Alternative Respiratory Pathway ◽  
Cytochrome Pathway ◽  
Defence Responses

Mitochondrial AOX (alternative oxidase) is the terminal oxidase of the CN (cyanide)-resistant alternative respiratory pathway in plants. To investigate the role of the tobacco AOX gene (NtAOX1a) (where Nt is Nicotiana tabacum) under deleterious conditions which could induce ROS (reactive oxygen species) accumulation, we generated and characterized a number of independent transgenic tobacco (N. tabacum) lines with altered NtAOX1a gene expression and AP (alternative pathway) capacity. AOX efficiently inhibited the production of low-temperature-induced H2O2 and might be a major enzyme for scavenging H2O2 at low temperature. Furthermore, NtAOX1a may act as a regulator of KCN-induced resistance to TMV (tobacco mosaic virus) through the regulation of H2O2. Notably, a moderate accumulation of H2O2 under the control of NtAOX1a was crucial in viral resistance. Analysis of seed germination indicated an important role for NtAOX1a in germination under H2O2-induced oxidative stress when the CP (cytochrome pathway) was inhibited. These results demonstrate that NtAOX1a is necessary for plants to survive low temperature, pathogen attack and oxidative stress by scavenging ROS under these adverse conditions when the CP is restricted.

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