Lipids

, Volume 28, Issue 1, pp 23–28

Phospholipids inDrosophila heads: Effects of visual mutants and phototransduction manipulations

Authors

  • William S. Stark
    • Division of Biological SciencesUniversity of Missouri
  • Teng-Nan Lin
    • Department of BiochemistryUniversity of Missouri
  • David Brackhahn
    • Department of BiochemistryUniversity of Missouri
  • J. Scott Christianson
    • Division of Biological SciencesUniversity of Missouri
  • Grace Y. Sun
    • Department of BiochemistryUniversity of Missouri
Article

DOI: 10.1007/BF02536355

Cite this article as:
Stark, W.S., Lin, T., Brackhahn, D. et al. Lipids (1993) 28: 23. doi:10.1007/BF02536355

Abstract

A procedure was developed to label phospholipids inDrosophila heads by feeding radioactive phosphate (32Pi). High-performance thin-layer chromatography showed label incorporation into various phospholipids. After 24 h of feeding, major phospholipids labeled were phosphatidylethanolamine (PE), 47%; phosphatidylcholine (PC), 24%; and phosphatidylinositol (PI), 12%.Drosophila heads have virtually no sphingomyelin as compared with mammalian tissues. Notable label was in ethanolamine plasmalogen, lysophosphatidylethanolamine, lysophosphatidylcholine and lysophosphatidylinositol. Less than 1% of the total label was in phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate. Other lipids labeled included phosphatidylserine, phosphatidic acid and some unidentified lipids. A time course (3–36 h) study revealed a gradual decrease in proportion of labeled PI, an increase in proportion of labeled PC and no obvious change in labeled PE. There were no significant differences in phospholipid labeling comparing theno receptorpotential (norpA) visual mutant and wild type under lightvs. dark conditions. However, overall32P labeling was higher in the wild type fed in the light as compared to the dark and tonorpA either in light or dark. This suggests that functional vision facilitates incorporation of label. Differences in phospholipid labeling were observed between young and aged flies, particularly in lysophospholipids and poly-PI, implicating phospholipase A2 function in recycling. Manipulations such as theouterrhabdomeresabsent andeyesabsent mutants and carotenoid deprivation failed to yield notable differences in phospholipid labeling pattern, suggesting that phospholipids important to vision may constitute only a minor portion of the total labeled pool in the head.

Abbreviations

cn bw

cinnabarbrown

DG

diacylglycerol

EDTA

ethylenediaminetetraacetic acid

EGTA

ethylene glycol-bis(β-aminoethyl ether)N,N,N′,N′ tetraacetic acid

eya

eyesabsent

GC

gas chromatography

HPTLC

high-performance thin-layer chromatography

IP3

mositol trisphosphate

LPC

lysophosphatidylcholine

LPE

lysophosphatidylethanolamine

LPI

lysophosphatidylinositol

NL

neutral lipids

norpA

no receptorpotential

ora

outerrhabdomeresabsent

PA

phosphatidic acid

PC

phosphatidylcholine

PE

phosphatidylethanolamine

PEpl

ethanolamine plasmalogen

Pi

inorganic phosphorus

PI

phosphatidylinositol

PIP

phosphatidylinositol 4-phosphate

PIP2

phosphatidylinositol 4,5-bisphosphate

PKC

protein kinase C

PLA2

phospholipiase A2

PLC

phospholipase C

PS

phosphatidylserine

TG

triglyceride

TLC

thin-layer chromatography

UN

unknowns

w

white

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Copyright information

© American Oil Chemists’ Society 1993