Expression of muscle-type phosphorylase in innervated and aneural cultured muscle of patients with myophosphorylase deficiency.
AUTOR(ES)
Martinuzzi, A
RESUMO
Patients with McArdle's myopathy lack muscle glycogen phosphorylase (M-GP) activity. Regenerating and cultured muscle of patients with McArdle's myopathy presents a glycogen phosphorylase (GP) activity, but it is not firmly established whether M-GP or non-M-GP isoforms are expressed. We have cultured myoblasts from biopsy specimen of five patients with McArdle's myopathy. Skeletal muscle was cultured aneurally or was innervated by coculture with fetal rat spinal cord explants. In the patients' muscle biopsies and in their cultured innervated and aneural muscle we studied total GP activity, isoenzymatic pattern, reactivity with anti-M-GP antiserum, and presence of M-GP mRNA. There was no detectable enzymatic activity, no immunoreactivity with anti-M-GP antiserum, and no M-GP mRNA in the muscle biopsy of all patients. GP activity, M-GP isozyme, and anti-M-GP antiserum reactivity were present in patients' aneural cultures, increased after innervation, and were undistinguishable from control. M-GP mRNA was demonstrated in both aneural and innervated cultures of patients and control by primer extension and PCR amplification of total RNA. Our studies indicate that the M-GP gene is normally transcribed and translated in cultured muscle of patients with myophosphorylase deficiency.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=288339Documentos Relacionados
- A muscle-type tropomyosin in human fibroblasts: evidence for expression by an alternative RNA splicing mechanism.
- KpnI RFLP at the human muscle-type phosphofructokinase (PFKM) gene locus
- Nicotine signals through muscle-type and neuronal nicotinic acetylcholine receptors in both human bronchial epithelial cells and airway fibroblasts
- Characterization of an enhancer upstream from the muscle-type promoter of a gene encoding 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase.
- Impairment of sympathetic activation during static exercise in patients with muscle phosphorylase deficiency (McArdle's disease).