Biomaterial Database

Myofibrillar M-band proteins represent constituents of native thick filaments, frayed filaments and bare zone assemblages. 1985

M Bähler, and T Wallimann, and H M Eppenberger

A-segments, native thick filaments, frayed filaments, bare zone assemblages, as well as completely disassembled and reassembled thick filaments from chicken pectoralis major were investigated for the presence of M-band proteins by the colloidal gold labelling technique. Specific polyclonal antibodies against the three M-band proteins identified to date, MM-creatine kinase, M-protein (165 kDa) and a 185 kDa protein myomesin, were prepared. Incubation with anti-M-protein and anti-myomesin antibodies resulted in heavy labelling of all thick filament types mentioned above, with the exception of the completely disassembled and reassembled thick filaments. In that case no labelling was detected with either antibody. In contrast, MM-creatine kinase which is an integral component of the intact M-band structure was detectable on isolated native thick filaments with lower frequency and to a variable extent. Also, bare zone assemblages were only rarely labelled by anti-MM-creatine kinase antibodies. This study shows that the 'cuff-like' additional material which had previously been observed in the middle of the bare zone of isolated thick filaments represent remnants of all three M-band proteins, whereas the extra material in intact bare zone assemblages mainly consists of myomesin and M-protein, but not of MM-creatine kinase. Myomesin and M-line protein may be important for the assembly and structural maintenance of thick filaments as well as for anchoring of additional M-band proteins, e.g. MM-creatine kinase which is bound less tightly to thick filaments and, in accordance with earlier results, seems to represent within the M-band some of the prominent bridge-forming structures.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009124	Muscle Proteins	The protein constituents of muscle, the major ones being ACTINS and MYOSINS. More than a dozen accessory proteins exist including TROPONIN; TROPOMYOSIN; and DYSTROPHIN.	Muscle Protein,Protein, Muscle,Proteins, Muscle
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
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D003402	Creatine Kinase	A transferase that catalyzes formation of PHOSPHOCREATINE from ATP + CREATINE. The reaction stores ATP energy as phosphocreatine. Three cytoplasmic ISOENZYMES have been identified in human tissues: the MM type from SKELETAL MUSCLE, the MB type from myocardial tissue and the BB type from nervous tissue as well as a mitochondrial isoenzyme. Macro-creatine kinase refers to creatine kinase complexed with other serum proteins.	Creatine Phosphokinase,ADP Phosphocreatine Phosphotransferase,ATP Creatine Phosphotransferase,Macro-Creatine Kinase,Creatine Phosphotransferase, ATP,Kinase, Creatine,Macro Creatine Kinase,Phosphocreatine Phosphotransferase, ADP,Phosphokinase, Creatine,Phosphotransferase, ADP Phosphocreatine,Phosphotransferase, ATP Creatine
D006046	Gold	A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000911	Antibodies, Monoclonal	Antibodies produced by a single clone of cells.	Monoclonal Antibodies,Monoclonal Antibody,Antibody, Monoclonal
D064211	Connectin	A giant elastic protein of molecular mass ranging from 2,993 kDa (cardiac), 3,300 kDa (psoas), to 3,700 kDa (soleus) having a kinase domain. The amino- terminal is involved in a Z line binding, and the carboxy-terminal region is bound to the myosin filament with an overlap between the counter-connectin filaments at the M line.	M-Band Proteins,M-Line 185 kDa Protein,M-Protein (muscle),Muscle M-Line Protein,Myomesin,Skelemins,Titin,Titin 1,Titin 2,Titin Kinase,alpha-Connectin,beta-Connectin,Kinase, Titin,M Band Proteins,M Line 185 kDa Protein,M-Line Protein, Muscle,Muscle M Line Protein,Protein, Muscle M-Line,Proteins, M-Band,alpha Connectin,beta Connectin