Expression of hybrid isomyosins in human skeletal muscle

Masanobu Wada*, Tadashi Okumoto, Kyoko Toro, Kazumi Masuda, Toru Fukubayashi, Kunio Kikuchi, Shigemitsu Niihata, Shigeru Katsuta

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

13 Citations (Scopus)


Myosin of human skeletal muscles was analyzed by means of several electrophoretic techniques. Myosin heavy chain (HC)-IIa- and HC-IIb-based isomyosins were identified by pyrophosphate-polyacrylamide gel electrophoresis (PP-PAGE). The electrophoretic mobilities of these fast- twitch muscle isomyosins differed in the order HC-IIa triplets < HC-IIb triplets. To determine the subunit composition of myosin molecules that function in intact muscle, two-dimensional electrophoresis in which the first and second dimensions were PP-PAGE and sodium dodecyl sulfate-PAGE, respectively, was also performed. Slow-twitch muscle isomyosin contained, in addition to slow-twitch light chain (LC) and HC-I isoforms, appreciable amounts of LC-2f, HC-IIa, and HC-IIb isoforms, and fast-twitch muscle isomyosin consisted of LC-2s and HC-I isoforms as well as fast-twitch LC and HC isoforms. Without consideration of HC- and slow-twitch alkali LC heterodimers, at least 31 possible isomyosins are derived from these findings on the subunit composition of isomyosins in human skeletal muscle.

Original languageEnglish
JournalAmerican Journal of Physiology - Cell Physiology
Issue number4 40-4
Publication statusPublished - 1996 Oct
Externally publishedYes


  • hybrid
  • myosin heavy chain
  • myosin light chain

ASJC Scopus subject areas

  • Clinical Biochemistry
  • Cell Biology
  • Physiology
  • Physiology (medical)


Dive into the research topics of 'Expression of hybrid isomyosins in human skeletal muscle'. Together they form a unique fingerprint.

Cite this