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

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal 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 Google Scholar Google Scholar Articles by Buesa, C. Articles by Hegardt, F. G. Search for Related Content PubMed PubMed Citation Articles by Buesa, C. Articles by Hegardt, F. G. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol 37, 2420-2432, Copyright © 1996 by Lipid Research, Inc.

ARTICLES

Aberrantly spliced mRNAs of the 3-hydroxy-3-methylglutaryl coenzyme A lyase (HL) gene with a donor splice-site point mutation produce hereditary HL deficiency

C Buesa, J Pie, A Barcelo, N Casals, C Mascaro, CH Casale, D Haro, M Duran, JA Smeitink and FG Hegardt
Unit of Biochemistry, School of Pharmacy, University of Barcelona, Spain.

A novel point mutation in the 3-hydroxy-3methyl-glutaryl coenzyme A lyase gene was found in a Turkish patient with homozygous 3-hydroxy-3- methylglutaric acidemia. Amplification by RT-PCR of the mRNA using a six different pairs of oligonucleotides produced no differences in four of the fragments amplified with respect to the control, but generated two fragments of different size. One was representative of a deletion of 126 bp and the other of an insertion of 78 bp. These abnormal mRNAs resulted from a G-->C transversion at the nucleotide +1 of an intron, which changed the invariant GT dinucleotide of the 5' donor splice site. This was associated with the occurrence of an alternative splicing, which led to the skipping of the whole exon of 126 bp, and also with the activation of one cryptic donor splice site in the same intron. These aberrant spliced mRNAs are predicted to encode two abnormal HMG-CoA lyase proteins: the first results in a protein with an internal deletion of 42 amino acids, whose enzyme activity is largely abolished, as the catalytic site was completely removed; the second contains 17 missense amino acids that precede a stop codon. Northern blot analysis showed that the overall content of these aberrantly spliced mRNAs in proband fibroblasts was the same as that found in control fibroblasts. However, hardly any transcript was observed corresponding to the inserted mutated mRNA when it was examined by a specific probe. To quantify the relative proportion of the two mRNAs, a quantitative RT-PCR (the DNA-mimic PCR reaction) was carried out. Results show that the proportion of the inserted mRNAs with respect to the deleted mRNA is only 1.2%. The father, mother, and two brothers of the proband were heterozygous in the G-->C mutation in the +1 nucleotide of the intron considered, while the two alleles of another brother were free of the mutation.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				X. Roca, R. Sachidanandam, and A. R. Krainer Intrinsic differences between authentic and cryptic 5' splice sites Nucleic Acids Res., November 1, 2003; 31(21): 6321 - 6333. [Abstract] [Full Text] [PDF]

				N. Casals, P. Gomez-Puertas, J. Pie, C. Mir, R. Roca, B. Puisac, R. Aledo, J. Clotet, S. Menao, D. Serra, et al. Structural ({beta}{alpha})8 TIM Barrel Model of 3-Hydroxy-3-methylglutaryl-Coenzyme A Lyase J. Biol. Chem., August 1, 2003; 278(31): 29016 - 29023. [Abstract] [Full Text] [PDF]