Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:4.1.1.6 (CAD)
 4,420 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Mitochondria are pleomorphic organelles that have central roles in cell physiology. Defects in their localization and dynamics lead to human disease. Myosins are actin-based motors that power processes such as muscle contraction, cytokinesis, and organelle transport. Here we report the initial characterization of myosin-XIX (Myo19), the founding member of a novel class of myosin that associates with mitochondria. The 970 aa heavy chain consists of a motor domain, three IQ motifs, and a short tail. Myo19 mRNA is expressed in multiple tissues, and antibodies to human Myo19 detect an approximately 109 kDa band in multiple cell lines. Both endogenous Myo19 and GFP-Myo19 exhibit striking localization to mitochondria. Deletion analysis reveals that the Myo19 tail is necessary and sufficient for mitochondrial localization. Expressing full-length GFP-Myo19 in A549 cells reveals a remarkable gain of function where the majority of the mitochondria move continuously. Moving mitochondria travel for many micrometers with an obvious leading end and distorted shape. The motility and shape change are sensitive to latrunculin B, indicating that both are actin dependent. Expressing the GFP-Myo19 tail in CAD cells resulted in decreased mitochondrial run lengths in neurites. These results suggest that this novel myosin functions as an actin-based motor for mitochondrial movement in vertebrate cells.
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PMID:Human Myo19 is a novel myosin that associates with mitochondria. 1993 26

Muscle contraction results from attachment-detachment cycles between myosin heads extending from myosin filaments and actin filaments. It is generally believed that a myosin head first attaches to actin, undergoes conformational changes to produce force and motion in muscle, and then detaches from actin. Despite extensive studies, the molecular mechanism of myosin head conformational changes still remains to be a matter for debate and speculation. The myosin head consists of catalytic (CAD), converter (CVD) and lever arm (LD) domains. To give information about the role of these domains in the myosin head performance, we have examined the effect of three site-directed antibodies to the myosin head on in vitro ATP-dependent actin-myosin sliding and Ca2+-activated contraction of muscle fibers. Antibody 1, attaching to junctional peptide between 50K and 20K heavy chain segments in the CAD, exhibited appreciable effects neither on in vitro actin-myosin sliding nor muscle fiber contraction. Since antibody 1 covers actin-binding sites of the CAD, one interpretation of this result is that rigor actin-myosin linkage is absent or at most a transient intermediate in physiological actin-myosin cycling. Antibody 2, attaching to reactive lysine residue in the CVD, showed a marked inhibitory effect on in vitro actin-myosin sliding without changing actin-activated myosin head (S1) ATPase activity, while it showed no appreciable effect on muscle contraction. Antibody 3, attaching to two peptides of regulatory light chains in the LD, had no significant effect on in vitro actin-myosin sliding, while it reduced force development in muscle fibers without changing MgATPase activity. The above definite differences in the effect of antibodies 2 and 3 between in vitro actin-myosin sliding and muscle contraction can be explained by difference in experimental conditions; in the former, myosin heads are randomly oriented on a glass surface, while in the latter myosin heads are regularly arranged within filament-lattice structures.
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PMID:Definite differences between in vitro actin-myosin sliding and muscle contraction as revealed using antibodies to myosin head. 2491 54

Objectives. We aim to explore urinary biomarkers that could monitor CAD in type 2 diabetic patients. Materials and Methods. Urine samples from two groups, twenty-eight type 2 diabetic patients with coexisting CAD and thirty type 2 diabetic patients without CAD, were purified by MB-WCX and then analyzed by MALDI-TOF-MS. Subsequently, we compared the urinary peptide signatures of the two groups by use of ClinProTools2.1 and evaluated the potential ability of the differently expressed peptides to distinguish type 2 diabetic patients with coexisting CAD from type 2 diabetic patients without CAD by ROC analysis. Finally, the differently expressed peptides were identified by nanoliquid chromatography-tandem mass spectrometry. Results. There were six differently expressed peptides (m/z 1305.2, 1743.9, 2184.9, 2756.1, 3223.2, and 6196.1) between the two groups of subjects, and they were identified as fragments of isoform 1 of fibrinogen alpha chain precursor, prothrombin precursor, and interalpha-trypsin inhibitor heavy chain H4. The diagnostic efficacy of m/z 2756.1 and m/z 3223.2 was better than the other peptides. Area under ROC of the m/z 2756.1, and m/z 3223.2 was 0.98 and 0.93, respectively. Conclusions. These urinary peptides are potential urinary biomarkers for monitoring of type 2 diabetic patients with CAD.
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PMID:The Difference Quantity of Urinary Peptides between Two Groups of Type 2 Diabetic Patients with or without Coronary Artery Disease. 2608 91