Linked Life Data

9414564

Source:http://linkedlifedata.com/resource/pubmed/id/9414564

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1998-2-23
pubmed:abstractText
Transgenic tobacco (Nicotiana tabacum L. cv W38) plants with an antisense gene directed against the mRNA of ribulose-1,5-biphosphate carboxylase/oxygenase (Rubisco) activase grew more slowly than wild-type plants in a CO2-enriched atmosphere, but eventually attained the same height and number of leaves. Compared with the wild type, the anti-activase plants had reduced CO2 assimilation rates, normal contents of chlorophyll and soluble leaf protein, and much higher Rubisco contents, particularly in older leaves. Activase deficiency greatly delayed the usual developmental decline in Rubisco content seen in wild-type leaves. This effect was much less obvious in another transgenic tobacco with an antisense gene directed against chloroplast-located glyceraldehyde-3-phosphate dehydrogenase, which also had reduced photosynthetic rates and delayed development. Although Rubisco carbamylation was reduced in the anti-activase plants, the reduction was not sufficient to explain the reduced photosynthetic rate of older anti-activase leaves. Instead, up to a 10-fold reduction in the catalytic turnover rate of carbamylated Rubisco in vivo appeared to be the main cause. Slower catalytic turnover by carbamylated Rubisco was particularly obvious in high-CO2-grown leaves but was also detectable in air-grown leaves. Rubisco activity measured immediately after rapid extraction of anti-activase leaves was not much less than that predicted from its degree of carbamylation, ruling out slow release of an inhibitor from carbamylated sites as a major cause of the phenomenon. Nor could substrate scarcity or product inhibition account for the impairment. We conclude that activase must have a role in vivo, direct or indirect, in promoting the activity of carbamylated Rubisco in addition to its role in promoting carbamylation.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-11536940, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16662500, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16663937, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16666614, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16666642, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16667398, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-16668555, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-7766043, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-7893695, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-7979237, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-8098529, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-8278543, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-8548451, http://linkedlifedata.com/resource/pubmed/commentcorrection/9414564-9046598
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
115
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1569-80
pubmed:dateRevised
2010-9-13
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Ribulose-1,5-bisphosphate carboxylase/oxygenase activase deficiency delays senescence of ribulose-1,5-bisphosphate carboxylase/oxygenase but progressively impairs its catalysis during tobacco leaf development.
pubmed:affiliation
Molecular Plant Physiology, Research School of Biological Sciences, Australian National University, Canberra, ACT, Australia.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't