TY - JOUR
T1 - Mutational analysis of the coding regions of the genes encoding protein kinase B-α and -β, phosphoinositide-dependent protein kinase-1, phosphatase targeting to glycogen, protein phosphatase inhibitor-1, and glycogenin
T2 - Lessons from a search for genetic variability of the insulin-stimulated glycogen synthesis pathway of skeletal muscle in NIDDM patients
AU - Hansen, Lars
AU - Fjordvang, Helle
AU - Rasmussen, Søren K.
AU - Vestergaard, Henrik
AU - Echwald, Søren M.
AU - Hansen, Torben
AU - Alessi, Dario
AU - Shenolikar, Shirish
AU - Saltiel, Alan R.
AU - Barbetti, Fabrizio
AU - Pedersen, Oluf
PY - 1999
Y1 - 1999
N2 - The finding of a reduced insulin-stimulated glucose uptake and glycogen synthesis in the skeletal muscle of glucose-tolerant first-degree relatives of patients with NIDDM, as well as in cultured fibroblasts and skeletal muscle cells isolated from NIDDM patients, has been interpreted as evidence for a genetic involvement in the disease. The mode of inheritance of the common forms of NIDDM is as yet unclear, but the prevailing hypothesis supports a polygenic model. In the present study, we tested the hypothesis that the putative inheritable defects of insulin-stimulated muscle glycogen synthesis might be caused by genetic variability in the genes encoding proteins shown by biochemical evidence to be involved in insulin-stimulated glycogen synthesis in skeletal muscle. In 70 insulin-resistant Danish NIDDM patients, mutational analysis by reverse transcription-polymerase chain reaction-single strand conformation polymorphism-heteroduplex analysis was performed on genomic DNA or skeletal muscle-derived cDNAs encoding glycogenin, protein phosphatase inhibitor-1, phosphatase targeting to glycogen, protein kinase B-α and -β, and the phosphoinositide-dependent protein kinase-1. Although a number of silent variants were identified in some of the examined genes, we found no evidence for the hypothesis that the defective insulin-stimulated glycogen synthesis in skeletal muscle in NIDDM is caused by structural changes in the genes encoding the known components of the insulin-sensitive glycogen synthesis pathway of skeletal muscle.
AB - The finding of a reduced insulin-stimulated glucose uptake and glycogen synthesis in the skeletal muscle of glucose-tolerant first-degree relatives of patients with NIDDM, as well as in cultured fibroblasts and skeletal muscle cells isolated from NIDDM patients, has been interpreted as evidence for a genetic involvement in the disease. The mode of inheritance of the common forms of NIDDM is as yet unclear, but the prevailing hypothesis supports a polygenic model. In the present study, we tested the hypothesis that the putative inheritable defects of insulin-stimulated muscle glycogen synthesis might be caused by genetic variability in the genes encoding proteins shown by biochemical evidence to be involved in insulin-stimulated glycogen synthesis in skeletal muscle. In 70 insulin-resistant Danish NIDDM patients, mutational analysis by reverse transcription-polymerase chain reaction-single strand conformation polymorphism-heteroduplex analysis was performed on genomic DNA or skeletal muscle-derived cDNAs encoding glycogenin, protein phosphatase inhibitor-1, phosphatase targeting to glycogen, protein kinase B-α and -β, and the phosphoinositide-dependent protein kinase-1. Although a number of silent variants were identified in some of the examined genes, we found no evidence for the hypothesis that the defective insulin-stimulated glycogen synthesis in skeletal muscle in NIDDM is caused by structural changes in the genes encoding the known components of the insulin-sensitive glycogen synthesis pathway of skeletal muscle.
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U2 - 10.2337/diabetes.48.2.403
DO - 10.2337/diabetes.48.2.403
M3 - Article
C2 - 10334321
AN - SCOPUS:0032896978
VL - 48
SP - 403
EP - 407
JO - Diabetes
JF - Diabetes
SN - 0012-1797
IS - 2
ER -