Planta

, Volume 224, Issue 2, pp 315–329

Genetic and biochemical evidence for involvement of HOTHEAD in the biosynthesis of long-chain α-,ω-dicarboxylic fatty acids and formation of extracellular matrix

  • Sergey Kurdyukov
  • Andrea Faust
  • Sandra Trenkamp
  • Sascha Bär
  • Rochus Franke
  • Nadia Efremova
  • Klaus Tietjen
  • Lukas Schreiber
  • Heinz Saedler
  • Alexander Yephremov
Original Article

DOI: 10.1007/s00425-005-0215-7

Cite this article as:
Kurdyukov, S., Faust, A., Trenkamp, S. et al. Planta (2006) 224: 315. doi:10.1007/s00425-005-0215-7

Abstract

In plants, extracellular matrix polymers built from polysaccharides and cuticular lipids have structural and protective functions. The cuticle is found to be ten times thinner in Arabidopsis thaliana (L.) Heynh than in many other plants, and there is evidence that it is unusual in having a high content of α-,ω-dicarboxylic fatty acids (FAs) in its polyesters. We designated the new organ fusion mutant hth-12 after it appeared to be allelic to adhesion of calyx edges (ace) and hothead (hth), upon molecular cloning of the gene by transposon tagging. This mutant is deficient in its ability to oxidize long-chain ω-hydroxy FAs to ω-oxo FAs, which results in leaf polyesters in decreased α-,ω-dicarboxylic FAs and increased ω-hydroxy FAs. These chemical phenotypes lead to disorder of the cuticle membrane structure in hth-12. ACE/HTH is a single-domain protein showing sequence similarity to long-chain FA ω-alcohol dehydrogenases from Candida species, and we hypothesize that it may catalyze the next step after cytochrome P450 FA ω-hydroxylases in the ω-oxidation pathway. We show that ACE/HTH is specifically expressed in epidermal cells. It appears very likely therefore that the changes in the amount of α-,ω-dicarboxylic FAs in hth-12 reflect the different composition of cuticular polyesters. The ACE/HTH gene is also expressed in root epidermal cells which do not form a polyester membrane on the exterior surface, thereby making it possible that the end products of the pathway, α-,ω-dicarboxylic FAs, are generally required for the cross-linking that ensures the integrity of the outer epidermal cell wall.

Keywords

ArabidopsisCuticleCutinDicarboxylic fatty acidsEpidermisExtracellular matrix

Abbreviations

GC–MS

Gas chromatography–mass spectrometry

RT-PCR

Reverse transcription-polymerase chain reaction

SEM

Scanning electron microscopy

TEM

Transmission electron microscopy

WT

Wild type

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Sergey Kurdyukov
    • 1
    • 4
  • Andrea Faust
    • 1
  • Sandra Trenkamp
    • 2
  • Sascha Bär
    • 1
  • Rochus Franke
    • 3
  • Nadia Efremova
    • 1
  • Klaus Tietjen
    • 2
  • Lukas Schreiber
    • 3
  • Heinz Saedler
    • 1
  • Alexander Yephremov
    • 1
  1. 1.Max-Planck-Institut für ZüchtungsforschungCologneGermany
  2. 2.Bayer AG, Bayer CropScience, ResearchTarget Research MonheimGermany
  3. 3.Institut für Zelluläre and Molekulare BotanikUniversität BonnBonnGermany
  4. 4.ARC Centre of Excellence for Integrative Legume Research, School of Environmental and Life SciencesUniversity of NewcastleCallaghanAustralia