Biomaterial Database

Fiber-type-specific expression of essential (alkali) myosin light chains in human skeletal muscles. 1996

K Jostarndt, and A Puntschart, and H Hoppeler, and R Billeter

Institute of Anatomy, University of Berne, Switzerland.

We studied the expression patterns of the essential (alkali) myosin light-chain isoforms in adult human skeletal muscles, using in situ hybridization and single-fiber protein analysis. In analogy to other species, we found that the fiber type-specific expression of essential myosin light chains is regulated via the availability of the respective mRNAs in a given fiber. In contrast to other species, the slow isoform 1sa was only expressed in the most oxidative Type I fibers (Subtype IA) in addition to 1sb. These fibers also contained high levels of carbonic anhydrase III. Within the fibers, the essential myosin light-chain mRNAs were located preferentially in the perinuclear regions and to a lesser extent in the intermyofibrillar spaces, a distribution that excludes cotranslational assembly of these light chains into the myofibrils as the main mechanism. In comparing leg and shoulder muscles, we found less distinct fiber typing in the expression patterns of the essential myosin light chains in the leg muscles than in muscles from the shoulder region.

UI	MeSH Term	Description	Entries
D007866	Leg	The inferior part of the lower extremity between the KNEE and the ANKLE.	Legs
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D009210	Myofibrils	The long cylindrical contractile organelles of STRIATED MUSCLE cells composed of ACTIN FILAMENTS; MYOSIN filaments; and other proteins organized in arrays of repeating units called SARCOMERES .	Myofilaments,Myofibril,Myofilament
D002256	Carbonic Anhydrases	A family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. They play an important role in the transport of CARBON DIOXIDE from the tissues to the LUNG. EC 4.2.1.1.	Carbonate Dehydratase,Carbonic Anhydrase,Anhydrases, Carbonic,Dehydratase, Carbonate
D005786	Gene Expression Regulation	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.	Gene Action Regulation,Regulation of Gene Expression,Expression Regulation, Gene,Regulation, Gene Action,Regulation, Gene Expression
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D001132	Arm	The superior part of the upper extremity between the SHOULDER and the ELBOW.	Brachium,Upper Arm,Arm, Upper,Arms,Arms, Upper,Brachiums,Upper Arms