Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-2-7
pubmed:abstractText
Embryos of Cuphea lanceolata have more than 80 mol% of decanoic acid ('capric acid') in their triacylglycerols, while this fatty acid is virtually absent in phosphatidylcholine (PtdCho). Seed development was complete 25-27 days after pollination, with rapid triacylglycerol deposition occurring between 9 and 24 days. PtdCho amounts increased until day 15 after pollination. Analysis of embryo lipids showed that the diacylglycerol (DAG) pool consisted of mainly long-chain molecular species, with a very small amount of mixed medium-chain/long-chain glycerols. Almost 100% of the fatty acid at position sn-2 in triacylglycerols (TAG) was decanoic acid. When equimolar mixtures of [14C]decanoic and [14C]oleic acid were fed to whole detached embryos, over half of the radioactivity in the DAG resided in [14C]oleate, whereas [14C]decanoic acid accounted for 93% of the label in the TAG. Microsomal preparations from developing embryos at the mid-stage of TAG accumulation catalysed the acylation of [14C]glycerol 3-phosphate with either decanoyl-CoA or oleoyl-CoA, resulting in the formation of phosphatidic acid (PtdOH), DAG and TAG. Very little [14C]glycerol entered PtdCho. In combined incubations, with an equimolar supply of [14C]oleoyl-CoA and [14C]decanoyl-CoA in the presence of glycerol 3-phosphate, the synthesized PtdCho species consisted to 95% of didecanoic and dioleic species. The didecanoyl-glycerols were very selectively utilized over the dioleoylglycerols in the production of TAG. Substantial amounts of [14C]oleate, but not [14C]decanoate, entered PtdCho. The microsomal preparations of developing embryos were used to assess the acyl specificities of the acyl-CoA:sn-glycerol-3-phosphate acyltransferase (GPAT, EC 2.3.1.15) and the acyl-CoA:sn-1-acyl-glycerol-3-phosphate acyltransferase (LPAAT, EC 2.3.1.51) in Cuphea lanceolata embryos. The efficiency of acyl-CoA utilization by the GPAT was in the order decanoyl = dodecanoyl greater than linoleoyl greater than myristoyl = oleoyl greater than palmitoyl. Decanoyl-CoA was the only acyl donor to be utilized to any extent by the LPAAT when sn-decanoylglycerol 3-phosphate was the acyl acceptor. sn-1-Acylglycerol 3-phosphates with acyl groups shorter than 16 carbon atoms did not serve as acyl acceptors for long-chain (greater than or equal to 16 carbon atoms) acyl-CoA species. On the basis of the results obtained, we propose a schematic model for triacylglycerol assembly and PtdCho synthesis in a tissue specialized in the synthesis of high amounts of medium-chain fatty acids.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-13671378, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-14173322, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-14299609, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-14455159, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-16665518, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-16667178, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-286305, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-3622518, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-4084230, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-4397675, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-4721605, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-475773, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-6465892, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-6833216, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-710426, http://linkedlifedata.com/resource/pubmed/commentcorrection/2264835-7288294
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0264-6021
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
272
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31-8
pubmed:dateRevised
2010-9-9
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Regulation of triacylglycerol biosynthesis in embryos and microsomal preparations from the developing seeds of Cuphea lanceolata.
pubmed:affiliation
Department of Plant Physiology, Swedish University of Agricultural Sciences, Uppsala.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't