Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study determined whether the beneficial effects of exercise training on the diabetic heart previously observed are associated with alterations in ventricular myosin heavy chain (MHC) isoform composition. Diabetes was induced in rats by i.v. streptozotocin. Trained rats were run on a treadmill for 60 min/day, 27 m/min, 10% grade. After 10 wks, ventricular MHC isoenzyme protein composition was analyzed for MHC composition using gel electrophoresis. alpha-MHC and beta-MHC mRNA were determined by Northern and slot blot hybridization techniques. Both protein and mRNA analyses indicated that sedentary control rats exhibited a predominance of alpha-MHC. Sedentary diabetics exhibited a shift to beta-MHC. Exercise trained diabetic rats showed a predominance of beta-MHC. The results indicate that treadmill exercise training of diabetic rat does not prevent the diabetes-induced shift in MHC composition towards the beta-MHC isoform, thus it is unlikely that the beneficial effects of exercise training on the diabetic heart, previously shown, are due to a normalization of the myosin isoform composition.
Mol Cell Biochem 1992 Nov 18
PMID:Effects of exercise training and diabetes on cardiac myosin heavy chain composition. 148 51

In muscle fibres labelled with iodoacetamidotetramethylrhodamine at Cys707 of the myosin heavy chain, the probes have been reported to change orientation when the fibre is activated, relaxed or put into rigor. In order to test whether these motions are indications of the cross-bridge power stroke, we monitored tension and linear dichroism of the probes in single glycerol-extracted fibres of rabbit psoas muscle during mechanical transients initiated by laser pulse photolysis of caged ATP and caged ADP. In rigor dichroism is negative, indicating average probe absorption dipole moments oriented more than 54.7 degrees away from the fibre axis. During activation from rigor induced by photoliberation of ATP from caged ATP in the presence of calcium, the dichroism reversed sign promptly (half-time 12.5 ms for 500 microM-ATP) upon release of ATP, but then changed only slightly during tension development 20 to 100 milliseconds later. During the onset of rigor following transfer of the fibre from an ATP-containing relaxing solution to a rigor medium lacking ATP, force generation preceded the change in dichroism. The dichroism change occurred slowly (half-time 47 s), because binding of ADP to sites within the muscle fibre limited its rate of diffusion out of the fibre. When ADP was introduced or removed, the dichroism transient was similar in time course and magnitude to that obtained after the introduction or removal of ATP. Neither adding nor removing ADP produced substantial changes in force. These results demonstrate that orientation of the rhodamine probes on the myosin head reflects mainly structural changes linked to nucleotide binding and release, rather than rotation of the cross-bridge during force generation.
J Mol Biol 1992 Jan 05
PMID:Transients in orientation of a fluorescent cross-bridge probe following photolysis of caged nucleotides in skeletal muscle fibres. 153 Sep 78

In vitro translation of RNA transported from the rat heart nuclei has suggested that the transport of translatable messages from hypertrophic heart nuclei is greater than from sham-operated heart nuclei. An increased translation activity was observed in cell-free system with RNA transported from sham-operated heart nuclei in presence of hypertrophic heart cytosol, than from sham-operated heart cytosol. Similar results were obtained when myosin heavy chain (MHC) mRNA in the transported RNA was analyzed by slot-blot hybridization using beta cDNA probe. Immunoprecipitation analysis of the translated products using beta MHC isozyme specific antibody indicated that the increased levels of beta MHC specific mRNA in the RNA transported from sham-operated heart nuclei in presence of hypertrophic heart cytosol than sham-operated heart cytosol. Direct quantitation of alpha and beta MHC messengers by slot-blot hybridization analysis of transported RNA using oligomeric probes corresponding to the 3' untranslated regions of alpha and beta MHC mRNAs revealed that an increased transport of both alpha and beta MHC specific mRNAs from sham-operated heart nuclei in the presence of hypertrophic heart cytosol occurs, of which beta MHC mRNA is more than that of alpha MHC. In contrast, slot-blot hybridization analysis of the radioactive RNA synthesized during transcription in vitro in nuclei obtained from sham-operated as well as hypertrophic hearts has shown an increased synthesis of alpha in sham nuclei and that of beta in hypertrophic heart nuclei. These results suggest that both transcriptional and post-transcriptional regulation may be operative in the expression of alpha and beta MHC genes during the development of cardiac hypertrophy.
Cell Mol Biol 1992 Feb
PMID:Effect of cytosol on the regulation of expression of myosin heavy chain genes during cardiac hypertrophy. 153 68

The complete amino acid sequence of a neuronal myosin heavy chain (MHC) from mammalian brain (1999 amino acids, 230 kDa) has been deduced by sequencing cDNA clones isolated from a rat brain cDNA library. The library was screened using an affinity-purified polyclonal antibody that had been raised against myosin purified from a neuronally-derived cell line (Neuro-2A). Restriction digests of genomic DNA from Neuro-2A cells and rat brain are consistent with an identity of the sequenced isoform from these two sources. RNA blot analysis demonstrates this myosin to exhibit differential expression within the cerebral cortex and spinal cord. No expression was observed in liver, kidney, heart, spleen or skeletal muscle, or even within other regions of the brain. The sequence of this neuronal MHC is compared with those of other non-muscle MHCs, to which it shows an overall similarity of structure, especially with respect to conserved regions within the head (ATP binding site, actin binding site, reactive thiols) and the presence of an alpha-helical coiled-coil tail that can be arranged as 28-residue repeating units plus four skip residues. A unique non-helical tailpiece composed of 72 amino acid residues marks the C-terminus of this neuronal myosin isoform.
J Mol Biol 1992 Apr 20
PMID:Cloning of the cDNA encoding a neuronal myosin heavy chain from mammalian brain and its differential expression within the central nervous system. 919 Mar 78

We have developed a simple method for producing embryonic stem (ES) cell lines whereby both alleles have been inactivated by homologous recombination and which requires a single targeting construct. Four different ES cell lines were created that were heterozygous for genes encoding two guanine nucleotide-binding protein subunits, alpha i2 and alpha i3, T-cell receptor alpha, and beta-cardiac myosin heavy chain. When these heterozygous cells were grown in high concentrations of G418, many of the surviving cells were homozygous for the targeted allele and contained two copies of the G418 resistance gene. This scheme provides an easy method for obtaining homozygous mutationally altered cells, i.e., double knockouts, and should be generally applicable to other genes and to cell lines other than ES cells. This method should also enable the production of cell lines in which more than one gene have had both alleles disrupted. These mutant cells should provide useful tools for defining the role of particular genes in cell culture.
Mol Cell Biol 1992 May
PMID:Production of homozygous mutant ES cells with a single targeting construct. 156 57

Comparisons of the nucleotide sequences of the light meromyosin (LMM) region of developmentally regulated fast chicken myosin heavy chain (MHC) isoforms indicates that chicken MHC isoforms are more similar to each other than to MHC isoforms in other species. The sequence data provide evidence that gene conversion events have occurred recently among the isoforms. An embryonic (Cemb1) isoform and neonatal isoform have the most extensive regions of sequence identity. Similar gene conversion events are present in the rat alpha- and beta-cardiac MHCs, but were not obvious in the LMM of developmentally regulated fast human MHC isoforms. The data suggest that gene conversion events can play a significant role in the evolution of the MHC multigene families and that concerted evolution of the chicken multigene family occurred after the divergence of mammals and avians.
J Mol Biol 1992 Jan 05
PMID:Gene conversions within the skeletal myosin multigene family. 173 Oct 85

The complete coding sequence of Onchocerca volvulus myosin heavy chain has been determined from a series of overlapping cDNAs. The protein sequences from the 2 filarids, one responsible for subcutaneous filariasis, the other for lymphatic filariasis, show 92% identity, and are 1957 amino acids long. Each protein sequence is also equally related, with 75% identity, to MHC-B, the protein encoded by the unc-54 gene of the free-living nematode C.elegans. Such analysis is useful in phylogenetic studies among nematodes, as well as in structure-function relationships among myosin isolates.
Mol Biochem Parasitol 1992 Feb
PMID:Comparison of the body wall myosin heavy chain sequences from Onchocerca volvulus and Brugia malayi. 174 Oct 12

We have previously shown that an antigen recognized by antibodies in sera of several microfilaremic individuals from a Wuchereria bancrofti endemic area bears strong homology to an invertebrate muscle protein. We have cloned and sequenced the entire gene containing this antigen encoding fragment and present data that confirms that the antigen is myosin heavy chain (MHC). This gene, which we have named Bmmyo-1 extends over 11 kb and has the potential to encode a protein of 1957 amino acids. The coding sequence is interrupted by 14 introns, most of which are larger than those in the myosin gene of the free-living nematode, Caenorhabditis elegans. The protein encoded by this gene bears greatest homology (75.1% identity) to the C. elegans myosin isoform MHC-B, encoded by the unc-54 gene. MHC-B is the major body wall myosin in C. elegans.
Mol Biochem Parasitol 1992 Feb
PMID:Characterization of a myosin heavy chain gene from Brugia malayi. 174 Oct 13

We have isolated and characterized five overlapping clones that encompass 3.2 kb and encode a part of the short subfragment 2, the hinge, and the light meromyosin regions of the myosin heavy chain rod as well as 143 bp of the 3' untranslated portion of the mRNA. Northern blot analysis showed expression of this mRNA mainly in ventricular muscle of the adult chicken heart, with trace levels detected in the atrium. Transient expression was seen in skeletal muscle during development and in regenerating skeletal muscle following freeze injury. To our knowledge, this is the first report of an avian ventricular myosin heavy chain sequence. Phylogenetic analysis indicated that this isoform is a distant homolog of other ventricular and skeletal muscle myosin heavy chains and represents a distinct member of the multigene family of sarcomeric myosin heavy chains. The ventricular myosin heavy chain of the chicken is either paralogous to its counterpart in other vertebrates or has diverged at a significantly higher rate.
J Mol Evol 1991 Oct
PMID:Structural and phylogenetic analysis of the chicken ventricular myosin heavy chain rod. 177 88

Familial Hypertrophic Cardiomyopathy (FHC) is a genetically inherited disorder of heart muscle. Over the past 40 years many studies have been done to describe in detail the clinical presentation of this disease and its associated pathophysiological consequences. The primary focus of this review is to discuss more recent studies involving the genetic mapping of one locus on chromosome 14, which causes FHC, and then to summarize studies demonstrating that this locus contains mutations in the cardiac myosin heavy chain genes. The chromosomal location of other putative FHC loci will also be considered. Finally, the implications of results that demonstrate that cardiac myosin heavy chain defects produce the pathophysiology of FHC will be considered from both clinical and basic research perspectives.
Mol Biol Med 1991 Apr
PMID:Mutations in cardiac myosin heavy chain genes cause familial hypertrophic cardiomyopathy. 180 60


1 2 3 4 5 6 7 8 9 10 Next >>