Activity of cholinephosphotransferase, lysolecithin: lysolecithin acyltransferase and lysolecithin acyltransferase in the developing mouse lung.
1. The present study presents the activity profiles of cholinephosphotransferase, lysolecithin:lysolecithin acyltransferase and lysolecithin acyltransferase at different stages of development of the mouse lung. 2. The specific activity of cholinephosphotransferase, a key enzyme in the de novo synthesis of phosphatidylcholine, increases during the later stages of fetal development until it reaches a maximal value at a gestational age of 17 days, i.e. 2 days before term. Thereafter, the activity of the enzyme declines again until around term. 2. The specific activity of lysolecithin:lysolecithin acyltransferase which catalyzes the transesterification between two molecules of 1-acyl-sn-glycero-3-phosphocholine, appears to be much lower than that of cholinephosphotransferase at gestational ages below 18 days. However, around day 18, the specific activity of lysolecithin:lysolecithin acyltransferase increases dramatically until it almost equals the maximal activity of cholinephosphotransferase measured on day 17. 4. The specific activity of lysolecithin acyltransferase, which catalyzes the direct acylation of 1-acyl-sn-glycero-3-phosphocholine, does not change significantly during the prenatal development and is lower than that of either lysolecithin:lysolecithin acyltransferase or cholinephosphotransferase at all stages of development. 5. These results are discussed in view of the possible role of these enzymes in the biosynthesis of pulmonary 1,2-dipalmitoyl-sn-glycero-3-phosphocholine.
D008243:1-Acylglycerophosphocholine O-Acyltransferase / Q000378:metabolism*; D000217:Acyltransferases / Q000378:metabolism*; D000375:Aging; D000818:Animals; D002798:Diacylglycerol Cholinephosphotransferase / Q000378:metabolism*; D005333:Fetus; D008168:Lung / Q000201:enzymology* / Q000254:growth & development; D008244:Lysophosphatidylcholines / Q000378:metabolism*; D051379:Mice; D010770:Phosphotransferases / Q000378:metabolism*
D008244:Lysophosphatidylcholines; D000217:Acyltransferases; D008243:1-Acylglycerophosphocholine O-Acyltransferase; D010770:Phosphotransferases; D002798:Diacylglycerol Cholinephosphotransferase