Human Molecular Genetics, 2001, Vol. 10, No. 9 911-918
© 2001 Oxford University Press
Missense mutation at the C-terminus of PAX6 negatively modulates homeodomain function
Department of Biochemistry and Molecular Biology, The University of Texas M.D. Anderson Cancer Center, Box 117, 1515 Holcombe Boulevard, Houston, TX 77030, USA
PAX6 is essential for ocular morphogenesis. Mutations in the PAX6 gene produce various phenotypes, including aniridia, Peters anomaly, foveal hypoplasia, autosomal dominant keratitis and congenital cataracts. PAX6 functions as a transcription factor and has two DNA binding domains (a paired domain and a homeodomain) which are joined by a linker, and a transactivation domain enriched in proline, serine and threonine (PST) at the C-terminus. The mechanism of PAX6 function is not clearly understood, and few target genes in vertebrates have been identified. We examined disease-causing missense mutations in the PST domain to understand how they affect the function of PAX6. Upon examining the DNA samples of aniridia patients, we identified three missense mutations in the PST domain: P375Q (a novel mutation) and the previously reported Q422R and X423L mutations. On the basis of functional analysis, the P375Q mutant appears to have a normal transactivation activity but lower DNA binding through the paired domain than the wild-type. The Q422R mutation resulted in the loss of DNA binding ability of the PAX6 homeodomain. Substitution analyses of the C-terminal amino acid (codon 422) indicated that an amino acid at codon 422 is required for DNA binding of the homeodomain of intact PAX6 and that the polarity and charge of the side-chain of the terminal amino acid influence this binding.
+ To whom correspondence should be addressed. Tel: +1 713 792 2690; Fax: +1 713 791 9478; Email: gsaunders@odin.mdacc.tmc.edu
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
J. Favor, C. J. Gloeckner, A. Neuhauser-Klaus, W. Pretsch, R. Sandulache, S. Saule, and I. Zaus Relationship of Pax6 Activity Levels to the Extent of Eye Development in the Mouse, Mus musculus Genetics, July 1, 2008; 179(3): 1345 - 1355. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. van Heyningen and K. A. Williamson PAX6 in sensory development Hum. Mol. Genet., May 15, 2002; 11(10): 1161 - 1167. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Planque, L. Leconte, F. M. Coquelle, P. Martin, and S. Saule Specific Pax-6/Microphthalmia Transcription Factor Interactions Involve Their DNA-binding Domains and Inhibit Transcriptional Properties of Both Proteins J. Biol. Chem., July 27, 2001; 276(31): 29330 - 29337. [Abstract] [Full Text] [PDF] |
||||


