Phospholipid and triacylglycerol profiles modified by PLD suppression in soybean seed

Plant Biotechnol J. 2011 Apr;9(3):359-72. doi: 10.1111/j.1467-7652.2010.00562.x. Epub 2010 Aug 27.

Abstract

Phospholipase D (PLD) is capable of hydrolyzing membrane phospholipids, producing phosphatidic acid. To alter phospholipid profiles in soybean seed, we attenuated PLD enzyme activity by an RNA interference construct using the partial sequence from a soybean PLDα gene. Two transgenic soybean lines were established by particle inflow gun (PIG) bombardment by co-bombarding with pSPLDi and pHG1 vectors. The lines were evaluated for the presence and expression of transgenes thoroughly through the T(4) generation. PLD-suppressed soybean lines were characterized by decreased PLDα enzyme activity and decreased PLDα protein both during seed development and in mature seeds. There was no change in total phospholipid amount; however, the PLD-attenuated transgenic soybean seed had higher levels of di18:2 (dilinoleoyl)-phosphatidylcholine (PC) and -phosphatidylethanolamine (PE) in seeds than the non-transgenic lines. The increased polyunsaturation was at the expense of PC and PE species containing monounsaturated or saturated fatty acids. In addition to increased unsaturation in the phospholipids, there was a decrease in unsaturation of the triacylglycerol (TAG) fraction of the soybean seeds. Considering recent evidence for the notion that desaturation of fatty acids occurs in the PC fraction and that the PC→DAG (diacylglycerol)→TAG pathway is the major route of TAG biosynthesis in developing soybean seed, the current data suggest that PLDα suppression slows the conversion of PC to TAG. This would be consistent with PLD playing a positive role in that conversion. The data indicate that soybean PLD attenuation is a potentially useful approach to altering properties of edible and industrial soybean lecithin.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Blotting, Southern
  • Gene Expression Regulation, Plant
  • Lysophosphatidylcholines / metabolism
  • Phospholipase D / genetics*
  • Phospholipase D / metabolism
  • Phospholipids / metabolism*
  • Plant Oils / metabolism
  • Plant Proteins / genetics
  • Plant Proteins / metabolism
  • Plants, Genetically Modified
  • Quantitative Trait, Heritable
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Restriction Mapping
  • Reverse Transcriptase Polymerase Chain Reaction
  • Seeds / enzymology*
  • Seeds / genetics
  • Soybeans / enzymology*
  • Soybeans / genetics
  • Spectrometry, Mass, Electrospray Ionization
  • Suppression, Genetic*
  • Transformation, Genetic
  • Triglycerides / metabolism*

Substances

  • Lysophosphatidylcholines
  • Phospholipids
  • Plant Oils
  • Plant Proteins
  • RNA, Messenger
  • Triglycerides
  • Phospholipase D