Source:http://linkedlifedata.com/resource/pubmed/id/16666428
Switch to
| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
4
|
| pubmed:dateCreated |
2010-6-29
|
| pubmed:abstractText |
Calcium transport into tomato (Lycopersicon esculentum Mill, cv Castlemart) fruit tonoplast vesicles was studied. Calcium uptake was stimulated approximately 10-fold by MgATP. Two ATP-dependent Ca(2+) transport activities could be resolved on the basis of sensitivity to nitrate and affinity for Ca(2+). A low affinity Ca(2+) uptake system (K(m) > 200 micromolar) was inhibited by nitrate and ionophores and is thought to represent a tonoplast localized H(+)/Ca(2+) antiport. A high affinity Ca(2+) uptake system (K(m) = 6 micromolar) was not inhibited by nitrate, had reduced sensitivity to ionophores, and appeared to be associated with a population of low density endoplasmic reticulum vesicles that contaminated the tonoplast-enriched membrane fraction. Arrhenius plots of the temperature dependence of Ca(2+) transport in tomato membrane vesicles showed a sharp increase in activation energy at temperatures below 10 to 12 degrees C that was not observed in red beet membrane vesicles. This low temperature effect on tonoplast Ca(2+)/H(+) antiport activity could only by partially ascribed to an effect of low temperature on H(+)-ATPase activity, ATP-dependent H(+) transport, passive H(+) fluxes, or passive Ca(2+) fluxes. These results suggest that low temperature directly affects Ca(2+)/H(+) exchange across the tomato fruit tonoplast, resulting in an apparent change in activation energy for the transport reaction. This could result from a direct effect of temperature on the Ca(2+)/H(+) exchange protein or by an indirect effect of temperature on lipid interactions with the Ca(2+)/H(+) exchange protein.
|
| pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-11538657,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16592937,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16662471,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16663457,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16663981,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16664154,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16664272,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16664540,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16664660,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16664693,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-16665635,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-17733807,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-2417316,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-4128882,
http://linkedlifedata.com/resource/pubmed/commentcorrection/16666428-4155469
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:status |
PubMed-not-MEDLINE
|
| pubmed:month |
Dec
|
| pubmed:issn |
0032-0889
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
88
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
1097-103
|
| pubmed:dateRevised |
2010-9-15
|
| pubmed:year |
1988
|
| pubmed:articleTitle |
Transport Properties of the Tomato Fruit Tonoplast : III. Temperature Dependence of Calcium Transport.
|
| pubmed:affiliation |
Department of Environmental Horticulture, University of California, Davis, California 95616.
|
| pubmed:publicationType |
Journal Article
|