Friday, 13 November 2015

.Chapter 4 – Lipid Metabolism in Plants


Abstract

Plants produce an immensely broad array of lipids, including components of membrane bilayers, storage oils, protective coatings, the photosynthetic machinery and signal transduction systems. Moreover, plant lipid metabolism involves complex interactions between prokaryote-derived plastids and a eukaryotic endomembrane network. Plastids, whose membranes are dominated by galactolipids assembled in situ, are the primary site of fatty acid synthesis and the 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway of isoprenoid synthesis. The endoplasmic reticulum dominates pathways requiring fatty acid elongation or oxygenation, most phospholipid assembly and the mevalonate pathway of isoprenoid synthesis. Some factors, such as fatty acid desaturation, involve an elaborate network of enzymes housed in both compartments.

Keywords

  • Cuticle;
  • Fatty acids;
  • Isoprenoids;
  • Plant lipid metabolism;
  • Seed oils

Abbreviations

ACCase
Acetyl-CoA carboxylase
ACP
Acyl carrier protein
DAG
Diacylglycerol
DGAT
Diacylglycerol acyltransferase
ER
Endoplasmic reticulum
GPAT
Glycerol-3-phosphate acyltransferase
IPP
Isopentenyl pyrophosphate
KAS
3-Ketoacyl-ACP synthase
KCS
β-Ketoacyl-CoA synthase
LPAAT
Lyso-phosphatidic acid acyltransferase
LPCAT
Lyso-phosphatidylcholine acyltransferase
MEP
2-C-methyl-D-erythritol 4-phosphate
MVA
Mevalonate
OPDA
Oxophytodienoic acid
PA
Phosphatidic acid
PC
Phosphatidylcholine
PDAT
Phospholipid:diacylglycerol acyltransferase
PDCT
Phosphatidylcholine:diacylglycerol cholinephosphotransferase
PE
Phosphatidylethanolamine
PG
Phosphatidylglycerol
TAG
Triacylglycerol

AcknowledgEments

Thanks are due to John B. Ohlrogge for his contributions to earlier editions of this chapter.