Anatomy of a homeoprotein revealed by the analysis of human MODY3 mutations.

Details

Serval ID
serval:BIB_5C74B72CC885
Type
Article: article from journal or magazin.
Collection
Publications
Title
Anatomy of a homeoprotein revealed by the analysis of human MODY3 mutations.
Journal
Journal of Biological Chemistry
Author(s)
Vaxillaire M., Abderrahmani A., Boutin P., Bailleul B., Froguel P., Yaniv M., Pontoglio M.
ISSN
0021-9258
Publication state
Published
Issued date
1999
Peer-reviewed
Oui
Volume
274
Number
50
Pages
35639-35646
Language
english
Notes
Journal Article --- Old month value: Dec 10
Abstract
Hepatocyte nuclear factor 1alpha (HNF1alpha) is an atypical dimeric homeodomain-containing protein that is expressed in liver, intestine, stomach, kidney, and pancreas. Mutations in the HNF1alpha gene are associated with an autosomal dominant form of non-insulin-dependent diabetes mellitus called maturity-onset diabetes of the young (MODY3). More than 80 different mutations have been identified so far, many of which involve highly conserved amino acid residues among vertebrate HNF1alpha. In the present work, we investigated the molecular mechanisms by which MODY3 mutations could affect HNF1alpha function. For this purpose, we analyzed the properties of 10 mutants resulting in amino acid substitutions or protein truncation. Some mutants have a reduced protein stability, whereas others are either defective in the DNA binding or impaired in their intrinsic trans-activation potential. Three mutants, characterized by a complete loss of trans-activation, behave as dominant negatives when transfected with the wild-type protein. These data define a clear causative relationship between MODY3 mutations and functional defects in HNF1alpha trans-activation. In addition, our analysis sheds new light on the structure of a homeoprotein playing a key role in pancreatic beta cell function.
Keywords
Amino Acid Substitution, DNA-Binding Proteins, Diabetes Mellitus, Type 2, Dimerization, Hemeproteins, Hepatocyte Nuclear Factor 1, Hepatocyte Nuclear Factor 1-alpha, Hepatocyte Nuclear Factor 1-beta, Humans, Mutagenesis, Site-Directed, Nuclear Proteins, Recombinant Proteins, Transcription Factors, Transcriptional Activation
Pubmed
Web of science
Open Access
Yes
Create date
24/01/2008 14:17
Last modification date
20/08/2019 14:14
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