Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085593 (chills)
 4,268 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Soybean (Glycine max Heihe No.23) seeds sensitive to imbibitional chilling injury were used to systematically investigate the effects of osmoregulation on the plasma membrane redox activity. Positive correlation was found between chilling tolerance and the plasma membrane redox activity. Osmoregulation pretreatment for 12 h significantly improved tolerance of seeds toward imbibitional chilling, the germination index, vigor index and TF content were increased, NADH and NADPH oxidation rates, Fe(CN)(3-)(6) and EDTA-Fe(3+) reduction rates were increased. Chilling tolerance of seeds increased as with duration of osmoregulation, and the rates of NADH oxidation, NADPH oxidation and Fe(CN)(3-)(6) reduction were improved, EDTA-Fe(3+) reduction rate was decreased after osmoregulation for 24 h, but higher than the control seed (seed not with osmoregulation).
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PMID:[Effect of osmoregulation on the plasma membrane redox activity in chilling injury sensitive soybean seeds]. 1562 15

Chilling injury is sustained by dry pollen of Typha latifolia L. upon hydration in germination medium at 0 degrees C. This injury is evidenced as poor germination, low vigor, and depressed respiration. Isolated mitochondria showed multiple sites of impaired electron transport. Besides losses of cytochrome (Cyt) c and NAD(+), the activities of membrane-bound enzyme complexes such as Cyt oxidase, NADH-duroquinone oxidoreductase, succinate-duroquinone oxidoreductase, and malate-duroquinone oxidoreductase were severely affected.Similarly, as in isolated mitochondria, in situ tests of mitochondrial activity showed that Cyt c was partially lost from its site of action. Re-addition of the lost Cyt c to the grains restored the N,N,N',N'-tetramethyl p-phenylenediamine dihydrochloride plus ascorbate-mediated electron transport from Cyt c to O(2), but did not significantly accelerate the overall O(2) uptake. Electron flow to duroquinone in the injured grains was low, indicating that lesions at the substrate side of ubiquinone determine the rate of O(2) consumption. Leakage of NAD(+), and also of adenylate phosphates and Krebs cycle substrates out of the injured grains, was considerable.Increasing the initial moisture content of the grains strongly enhanced their resistance to cold hydration. Below 17% moisture content (fresh weight basis), the decrease in vigor closely matched the loss of NAD(+) and adenosine phosphates. Vitality was irreversibly lost by cold hydration below 10 to 12% initial moisture content.Injury to dry pollen was prevented by imbibition at 27 degrees C. Decrease of vigor and increased leakage, however, started below 20 degrees C, and complete loss of vitality occurred below 10 degrees C.These results are interpreted as evidence that loss of membrane integrity is the primary cause of imbibitional chilling injury.
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PMID:Imbibitional chilling injury in pollen: involvement of the respiratory chain. 1666 16

The mosaic MSC16 cucumber (Cucumis sativus L.) mutant, which houses a rearranged mitochondrial genome, has altered respiratory chain activity, with a dysfunctional Complex I, increased external NADH dehydrogenases (ND(ex)) activity, and a higher alternative oxidase (AOX) capacity and AOX protein level. In the present study, changes in oxidative defense metabolism resulting from the respiratory chain dysfunction in the MSC16 mutant were compared with those induced by chilling. Chilling increased the enzymatic and non-enzymatic antioxidant defense systems in the wild-type (WT) but not in MSC16, which displays elevated antioxidant defenses as a result of the mitochondrial mutation. The high AOX capacity and protein level in MSC16 were unchanged as a result of chilling, whereas chilling increased these parameters in WT leaves. In mitochondria isolated from WT plants, superoxide was produced to a similar extent in the matrix and the intermembrane space, but in MSC16 mitochondria superoxide was produced largely within the intermembrane space. Mitochondria isolated from both genotypes after chilling showed increased superoxide production within the intermembrane space. Cytochemical detection revealed an increased abundance of H2O2 in the mitochondrial membrane in mesophyll cells of MSC16 leaves. The mitochondrial mutation also resulted in changes in the antioxidative defense system, including AOX, which were similar to those observed following chilling. The results presented here support the hypothesis that AOX is an effective marker of the cellular reprogramming resulting from stress. Moreover, we propose a role for reactive oxygen species (ROS) generated within the mitochondria in signal transduction.
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PMID:Chilling stress and mitochondrial genome rearrangement in the MSC16 cucumber mutant affect the alternative oxidase and antioxidant defense system to a similar extent. 1954 67