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  • The EMBO Journal (2002) 21, 2912 - 2922
  • doi:10.1093/emboj/cdf300

Control of germination and lipid mobilization by COMATOSE, the Arabidopsis homologue of human ALDP

Steven Footitt1,7, Stephen P. Slocombe2,7, Victoria Larner3,7, Smita Kurup4, Yaosheng Wu2,5, Tony Larson6, Ian Graham6, Alison Baker2 and Michael Holdsworth1

  1. IACR-Long Ashton Research Station, Department of Agricultural Sciences, University of Bristol, Long Ashton, Bristol BS41 9AF, UK
  2. Centre for Plant Sciences, Leeds Institute for Plant Biotechnology and Agriculture (LIBA), Irene Manton Building, University of Leeds, Leeds LS2 9JT, UK
  3. Present address: Department of Biological Sciences, University of Warwick, Coventry CV4 7AL, UK
  4. Present address: Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK
  5. Present address: Pre Clinical Sciences Department, Guangxi Medical University, 6 Binhu Road, Nanning, Guangxi 530021, P.R. China
  6. Centre for Novel Agricultural Products, Department of Biology, University of York, PO Box 373, York YO10 5YW, UK
  7. S.Footitt, S.P.Slocombe and V.Larner contributed equally to this work

Correspondence to:

Michael Holdsworth, E-mail: mike.holdsworth@bbsrc.ac.uk

Received 13 March 2002; Accepted 23 April 2002

Embryo dormancy in flowering plants is an important dispersal mechanism that promotes survival of the seed through time. The subsequent transition to germination is a critical control point regulating initiation of vegetative growth. Here we show that the Arabidopsis COMATOSE (CTS) locus is required for this transition, and acts, at least in part, by profoundly affecting the metabolism of stored lipids. CTS encodes a peroxisomal protein of the ATP binding cassette (ABC) transporter class with significant identity to the human X-linked adrenoleukodystrophy protein (ALDP). Like X-ALD patients, cts mutant embryos and seedlings exhibit pleiotropic phenotypes associated with perturbation in fatty acid metabolism. CTS expression transiently increases shortly after imbibition during germination, but not in imbibed dormant seeds, and genetic analyses show that CTS is negatively regulated by loci that promote embryo dormancy through multiple independent pathways. Our results demonstrate that CTS regulates transport of acyl CoAs into the peroxisome, and indicate that regulation of CTS function is a major control point for the switch between the opposing developmental programmes of dormancy and germination.

  • Keywords:

    • ABC lipid transporter,
    • adrenoleukodystrophy,
    • Arabidopsis,
    • dormancy,
    • germination