High impact information on LOC396507

• The tail, but not the head portion of M-CK is essential for the association of M-CK with the M-band of myofibrils [1].
• Partial protein sequences of dog muscle (M) CK and brain (B) CK subunits were determined and compared with the derived amino acid sequence of the myocardial enzyme and of M CK subunits of other species [2].
• Immunogold localization of muscle-type MM-CK on ultrathin cryosections of muscle, after removal of soluble CK, revealed relatively strong in situ labeling of M-CK remaining bound to the M band as well as to the SR membranes [3].
• During the first 2 days of culture of myogenic chicken cells only minute amounts of mRNA for a subunit of creatine kinase, M-CK, could be found in cultures from the 3rd and 4th day; however, a dramatic increase of mRNA for the muscle-specific M-CK was observed [4].
• Interestingly, in limb mesenchyme cultures, significant M-CK expression was detected during chondrogenesis (days 2-7), whereas hypertrophic cells expressed only B-CK [5].

Biological context of LOC396507

• Intermediate levels of gene activity were observed for TnI enhancers containing E-boxes derived from the MCK left E-box site or from the Ig kappa E2 E-box [6].
• Within the TnI enhancer, the E-box sequence derived from cardiac alpha-actin was inactive whereas the corresponding sequence from the MCK right E-box efficiently restored wild-type enhancer activity in muscle cells [6].
• The distinct nucleotide sequences of H4 insert DNA and M-CK cDNA were translated into 82% homologous amino acid sequences [7].

Anatomical context of LOC396507

• Expression of B-CK increased slightly over 15 days in mineralizing, retinoic acid-treated cephalic chondrocytes, but it decreased in nonmineralizing caudal chondrocytes, while there was little expression of M-CK [5].
• In the growth plate, B-CK expression was highest in the most calcified regions, and M-CK was less abundant than B-CK in all regions of the growth plate [5].
• In differentiated myogenic cells, the myotubes, both M-CK and B-CK subunits are synthesized [8].
• A competition e.l.i.s.a. (enzyme-linked immunosorbent assay) is described that enables direct measurement of the muscle-specific polypeptide of chick creatine kinase (M-CK) in extracts of differentiating muscle-cell cultures and in blood plasma samples, even in the presence of embryonic, or brain-type, creatine kinase [9].
• The rates of degradation of creatine kinase subunits, M-CK and B-CK subunits, were measured in cultured myogenic cells and in subcultured fibroblasts [8].

Associations of LOC396507 with chemical compounds

• The assay was shown to be reproducible and gave a linear response with increasing amounts of RNA, allowing relative quantitation of mRNA in polysomal RNA for the creatine kinases M and B. MRNA for M-CK was detected in polusomal RAN and total cellular RNA from myogenic cells [10].
• Myofibrillar binding is mediated by major and minor lysine charge clamp motifs (K104/K115 [major] and K8/K24 [minor] in chicken M-CK) located in the N-terminal region [J. Cell Biol. 149 (2000) 1225] [11].
• The localization of M-CK at the I-band coincided with that of adenylate kinase and aldolase [12].

Analytical, diagnostic and therapeutic context of LOC396507

• E.l.i.s.a. measurements on 17-20-day embryonic thigh-muscle extracts, which contain almost exclusively M-CK, agree well with enzyme activity and radioimmunoassay [9].
• Proteolytically modified M-CK and B-CK subunits were able to refold and reassociate into dimeric structures after treatment with high concentrations of LiCl and at low pH [13].

References