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  • The EMBO Journal (2002) 21, 1063 - 1073
  • doi:10.1093/emboj/21.5.1063

A Caenorhabditis elegans TGF-bold beta, DBL-1, controls the expression of LON-1, a PR-related protein, that regulates polyploidization and body length

Kiyokazu Morita1,2, Anthony J. Flemming3, Yukiko Sugihara1, Makoto Mochii1,4, Yo Suzuki5, Satoru Yoshida1, William B. Wood5, Yuji Kohara6, Armand M. Leroi3 and Naoto Ueno1

  1. Department of Developmental Biology, National Institute for Basic Biology, and Department of Biomechanics, The Graduate University for Advanced Studies, Okazaki 444-8585, Japan
  2. Present address: Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309-0347, USA
  3. Department of Biological Sciences, Imperial College at Silwood Park, Ascot, Berkshire SL5 7PY, UK
  4. Present address: Department of Life Science, Himeji Institute of Technology, Hyogo 678-1297, Japan
  5. Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO 80309-0347, USA
  6. Genome Biology Laboratory, National Institute of Genetics, Mishima 411-8540, Japan

Correspondence to:

Naoto Ueno, E-mail: nueno@nibb.ac.jp

Received 8 May 2001; Accepted 8 January 2002; Revised 6 December 2001

Using cDNA-based array analysis combined with double-stranded RNA interference (dsRNAi), we have identified yk298h6 as a target gene of Caenorhabditis elegans TGF-beta signaling. Worms overexpressing dbl-1, a TGF-beta ligand, are 16% longer than wild type. Array analysis shows yk298h6 to be one of several genes suppressed in such worms. Disruption of yk298h6 function by dsRNAi also resulted in long worms, suggesting that it is a negative regulator of body length. yk298h6 was then mapped to, and shown to be identical to, lon-1, a known gene that affects body length. lon-1 encodes a 312 amino acid protein with a motif sequence that is conserved from plants to humans. Expression studies confirm that LON-1 is repressed by DBL-1, suggesting that LON-1 is a novel downstream component of the C.elegans TGF-beta growth regulation pathway. Consistent with this, LON-1 is expressed mainly in the larval and adult hypodermis and has dose-dependent effects on body length associated with changes in hypodermal ploidy, but not hypodermal cell proliferation.

  • Keywords:

    • body length,
    • Caenorhabditis elegans,
    • hypodermis,
    • polyploidization,
    • TGF-beta