Linked Life Data

16669081

Source:http://linkedlifedata.com/resource/pubmed/id/16669081

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-6-29
pubmed:abstractText
Biosynthesis of very long chain (>C(18)) fatty acids (VLCFAs) and the pathway for their incorporation into acyl lipids was studied in microspore-derived (MD) and zygotic embryos of Brassica napus L. cv Reston. In the presence of [1-(14)C]oleoyl-coenzyme A or [1-(14)C] eicosenoyl-coenzyme A, malonyl-coenzyme A, and reducing equivalents, maximal in vitro elongation activity was expressed in protein preparations from early-mid cotyledonary stage MD embryos (17-20 days in culture), when endogenous eicosenoic (20:1) and erucic (22:1) acids were just beginning to accumulate (approximately 1.5 milligrams per gram dry weight). The biosynthesis of VLCFAs and their incorporation into glycerolipids in vitro in the MD embryo system occurred at rates comparable to those measured in developing zygotic Reston embryos at about 20 days postanthesis. When glycerol-3-phosphate was supplied as acyl acceptor in time-course experiments using homogenates prepared from 18-day MD embryos, newly synthesized [(14)C]20:1 and [(14)C]22:1 were incorporated primarily into triacylglycerols (TAGs) and, to a lesser extent, into lyso-phosphatidic/phosphatidic acids, diacylglycerols, and phosphatidylcholines as well as the acyl-coenzyme A and free fatty acid pools. [(14)C]24:1 was not detected in any acyl lipid. Stereospecific analyses of the radiolabeled TAGs indicated that [(14)C]20:1 and [(14)C]22:1 moieties were esterified predominantly at the sn-3 position, but were also found at the sn-1 position. [(14)C]20:1, but not [(14)C]22:1, was detected at the sn-2 position. Similar patterns of (14)C-labeled VLCFA distribution were obtained in experiments conducted using a 15,000g pellet fraction from 18-day MD embryos. All trends observed in the formation of TAGs containing VLCFAs in the Reston MD embryo system were also confirmed in studies of zygotic embryos of the same cultivar. The data support the biosynthesis of 20:1 and then 22:1 via successive condensations of malonyl-coenzyme A with oleoyl-coenzyme A and, for the first time in B. napus, demonstrate the incorporation of newly synthesized VLCFAs into TAGs via the Kennedy pathway.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-13865278, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16661495, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16661496, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16663345, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16666279, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16666545, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16666885, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16667739, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-16668417, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-2327575, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-4155683, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-4950467, http://linkedlifedata.com/resource/pubmed/commentcorrection/16669081-942051
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Aug
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
99
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1609-18
pubmed:dateRevised
2010-9-15
pubmed:year
1992
pubmed:articleTitle
Biosynthesis of Acyl Lipids Containing Very-Long Chain Fatty Acids in Microspore-Derived and Zygotic Embryos of Brassica napus L. cv Reston.
pubmed:affiliation
Plant Biotechnology Institute, National Research Council of Canada, 110 Gymnasium Place, Saskatoon, Saskatchewan, S7N 0W9, Canada.
pubmed:publicationType
Journal Article