title: Electrophoretic mobility of cardiac myosin heavy chain isoforms revisited: application of MALDI TOF/TOF analysis.
abstract: The expression of two cardiac myosin heavy chain (MyHC) isoforms in response to the thyroid status was studied in left ventricles (LVs) of Lewis rats. Major MyHC isoform in euthyroid and hyperthyroid LVs had a higher mobility on SDS-PAGE, whereas hypothyroid LVs predominantly contained a MyHC isoform with a lower mobility corresponding to that of the control soleus muscle. By comparing the MyHC profiles obtained under altered thyroid states together with the control soleus, we concluded that MyHCα was represented by the lower band with higher mobility and MyHCβ by the upper band. The identity of these two bands in SDS-PAGE gels was confirmed by western blot and mass spectrometry. Thus, in contrast to the literature data, we found that the MyHCα possessed a higher mobility rate than the MyHCβ isoform. Our data highlighted the importance of the careful identification of the MyHCα and MyHCβ isoforms analyzed by the SDS-PAGE.
authors.affiliation: Department of Physiology, Faculty of Science, Charles University in Prague, 12843 Prague, Czech Republic.
authors.forename: Petra
authors.initials: P
authors.lastname: Arnostova
authors.forename: Petr L
authors.initials: PL
authors.lastname: Jedelsky
authors.forename: Tomáš
authors.initials: T
authors.lastname: Soukup
authors.forename: Jitka
authors.initials: J
authors.lastname: Zurmanova
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D005260:Female; D006980:Hyperthyroidism / Q000378:metabolism; D007037:Hypothyroidism / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D018995:Myosin Heavy Chains / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D020033:Protein Isoforms; D051381:Rats; D011917:Rats, Inbred Lew; D016415:Sequence Alignment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D024723:Ventricular Myosins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism
chemical_list: D020033:Protein Isoforms; D024723:Ventricular Myosins; D018995:Myosin Heavy Chains