HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Raz-Prag, D. Articles by Sieving, P. A. Search for Related Content PubMed PubMed Citation Articles by Raz-Prag, D. Articles by Sieving, P. A.

Haploinsufficiency Is Not the Key Mechanism of Pathogenesis in a Heterozygous Elovl4 Knockout Mouse Model of STGD3 Disease

¹From the NIDCD/NEI, National Institutes of Health, Bethesda, Maryland; ²Ophthalmology and Visual Sciences, W. K. Kellogg Eye Center, University of Michigan, Ann Arbor, Michigan; ³Biological Imaging Core, National Eye Institute, Bethesda, Maryland; ⁴Laboratory of Membrane Biochemistry and Biophysics, NIAAA, Bethesda, Maryland; and the ⁵Department of Ophthalmics Research, Merck Research Laboratories, West Point, Pennsylvania.

PURPOSE. Autosomal dominant Stargardt-like (STGD3) disease results from mutations in the ELOVL4 gene (elongation of very-long-chain fatty acids). This study was undertaken to characterize a mouse model with a targeted deletion of Elovl4 and to explore the role of this gene in retinal/macular degeneration.

METHODS. A construct targeted to exon 2 of the Elovl4 gene was used to suppress expression of the gene. Elovl4 homozygous pups were nonviable and were not available for study. Hence, the analysis was performed on heterozygous Elovl4^+/– mice 16 to 22 month of age and littermate wild-type (WT) control mice of the same age. Characterization included examining gene message and protein levels, electroretinogram (ERG), retinal morphology and ultrastructure, and plasma and retinal fatty acid composition.

RESULTS. Although the level of Elovl4 mRNA was reduced in Elovl4^+/– retinas, only minimal morphologic abnormalities were found, and the retinal (ERG) function was essentially normal in Elovl4^+/– retinas compared with the WT control retinas. Systemic fatty acid profiles of Elovl4^+/– mice were unremarkable, although the concentration of several fatty acids was significantly lower in Elovl4^+/– retinas, particularly the monounsaturated fatty acids.

CONCLUSIONS. The detailed characterization of this animal model provides the first in vivo evidence that Elovl4 haploinsufficiency is not the underlying key disease mechanism in STGD3. The results are consistent with a dominant negative mechanism for the deletion mutation. The Elovl4 knockout mouse is one of three complementary animal models that will help elucidate the disease mechanism.

This article has been cited by other articles:

				V. Vasireddy, Y. Uchida, N. Salem Jr, S. Y. Kim, M. N. A. Mandal, G. B. Reddy, R. Bodepudi, N. L. Alderson, J. C. Brown, H. Hama, et al. Loss of functional ELOVL4 depletes very long-chain fatty acids (>=C28) and the unique {omega}-O-acylceramides in skin leading to neonatal death Hum. Mol. Genet., March 1, 2007; 16(5): 471 - 482. [Abstract] [Full Text] [PDF]