Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-6-29
pubmed:abstractText
An important part in the understanding of the regulation of carbon partitioning within the leaf is to investigate the endogenous variations of parameters related to carbon metabolism. This study of diurnal changes in the activities of sucrose-synthesizing enzymes and levels of nonstructural carbohydrates in intact leaves of field-grown soybean plants (Glycine max [L.]) showed pronounced diurnal fluctuations in sucrose phosphate synthase (SPS) activity. However, there was no distinct diurnal change in the activity of fructose-1,6-bisphosphatase (F1,6BPase). SPS activity in leaves from plants grown in controlled environments presented two peaks during the light period. In contrast to field-grown plants, F1,6BPase activity in leaves from growth chamber-grown plants manifested one peak during the first half of the light period. In plants grown under both conditions, sucrose and starch accumulation rates were highest during early hours of the light period. By the end of the dark period, most of the starch was depleted. A pattern of diurnal fluctuations of abscisic acid (ABA) levels in leaves was also observed under all growing conditions. Either imposition of water stress or exogenous applications of ABA inhibited F1,6BPase activity. However, SPS-extractable activity increased following water deficit but did not change in response to ABA treatment. Gibberellin application to intact soybean leaves increased levels of both starch and sucrose. Both gibberellic acid (10(-6)m) and gibberellins 4 and 7 (10(-5)m) increased the activity of SPS but had an inconsistent effect on F1,6BPase. Correlation studies between the activities of SPS and F1,6BPase suggest that these two enzymes are coordinated in their function, but the factors that regulate them may be distinct because they respond differently to certain environmental and physiological changes.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16659857, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16660097, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16661469, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16661753, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16662277, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16662913, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16663233, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16663648, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16663664, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16663791, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16663836, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16665174, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-16665237, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-210163, http://linkedlifedata.com/resource/pubmed/commentcorrection/16653110-5781434
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Nov
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
100
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1230-7
pubmed:dateRevised
2010-9-14
pubmed:year
1992
pubmed:articleTitle
Regulation of key enzymes of sucrose biosynthesis in soybean leaves : effect of dark and light conditions and role of gibberellins and abscisic Acid.
pubmed:affiliation
Department of Horticultural Science, University of Minnesota, St. Paul, Minnesota 55108.
pubmed:publicationType
Journal Article