Comparative transcriptional and biochemical studies in muscle of myotonic dystrophies (DM1 and DM2).

Full Abstract

Myotonic dystrophy type 1 (DM1) and myotonic dystrophy type 2 (proximal muscular myopaty/DM2) are caused by similar dynamic mutations at two distinct genetic loci. The two diseases also lead to similar phenotypes but different clinical severity. Dysregulation of alternative splicing has been suggested as the common pathogenic mechanism. Here, we investigate the molecular differences between DM1 and DM2 using reverse transcriptase-polymerase chain reaction of troponin T (TnT) and the insulin receptor (IR), as well as immunoblotting of TnT in muscle biopsies from DM1 and DM2 patients. We found that: (a) slow TnT was encoded by two different transcripts in significantly different ratios in DM1 and DM2 muscles; (b) DM2 muscles exhibited a higher degree of alternative splicing dysregulation for fast TnT transcripts when compared to DM1 muscles; (c) the distribution of TnT proteins was significantly skewed towards higher molecular weight species in both diseases; (d) the RNA for the insulin-independent IR-A isoform was significantly increased and appeared related to the fibre-type composition in the majority of the cases examined. On the whole, these data should give a better insight on pathogenesis of DM1 and DM2.

Author information

Author/s: Salvatori, Sergio (S); Furlan, Sandra (S); Fanin, Marina (M); Picard, Anne (A); Pastorello, Ebe (E); Romeo, Vincenzo (V); Trevisan, Carlo Pietro (CP); Angelini, Corrado (C);

Affiliation: Department of Biomedical Sciences, University of Padova, viale G. Colombo 3, Padua, Italy. sergio.salvatori(-atsign-)unipd.it

Journal and publication information

Publication Type: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't

Journal: Neurological sciences : official journal of the Italian Neurological Society and of the Italian Society of Clinical Neurophysiology (Neurol Sci), published in Italy. (Language: eng)

Reference: 2009-Jun; vol 30 (issue 3) : pp 185-92

Dates: Created 2009/05/18; Completed 2009/09/14;

PMID: 19326042, status: MEDLINE (last retrieved date: 9/14/2009)

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.