Title: A G220V substitution within the N-terminal transcription regulating domain of HOXD13 causes a variant synpolydactyly phenotype
Authors: Fantini, Sebastian ×
Vaccari, Giulia
Brison, Nathalie
Debeer, Philippe
Tylzanowski, Przemyslaw
Zappavigna, Vincenzo #
Issue Date: Mar-2009
Publisher: IRL Press
Series Title: Human Molecular Genetics vol:18 issue:5 pages:847-860
Abstract: The 5' members of the HoxD gene cluster (paralogous groups 9-13) are crucial for correct vertebrate limb patterning. Mutations in the HOXD13 gene have been found to cause synpolydactyly (SPD) and other limb malformations in human. We report the identification in a Greek family of variant form of SPD caused by a novel missense mutation that substitutes glycine for valine in position 220 (G220V) of HOXD13. This mutation represents the first substitution of an amino acid located outside of the HOXD13 homeodomain that causes autopodal limb malformations. We have characterized this mutation at the molecular level and found that the G220V substitution causes a significant impairment of the capacity of HOXD13 to bind DNA and regulate transcription. HOXD13(G220V) was found to be deficient in both activating and repressing transcription through HOXD13-responsive regulatory elements. In accordance with these results, a comparison of the activities of HOXD13 and HOXD13(G220V) in vivo using retrovirus-mediated misexpression in developing chick limbs, showed that the G220V mutation impairs the capacity of HOXD13 to perturb the development of proximal limb skeletal elements and to ectopically activate the transcription of the Hand2 target gene. We moreover show that the G220V mutation compromises the stability of the HOXD13 protein within cells and causes its partial accumulation in the cytosol in the form of subtle aggregates. Taken together, our results establish that the G220V substitution does not produce a dominant-negative effect or a gain-of-function, but represents a dominant loss-of-function mutation revealing haploinsufficiency of HOXD13 in human.
ISSN: 0964-6906
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Orthopaedics Section (-)
Rheumatology Section (-)
Clinical Genetics
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science