Immunocytochemical investigations of muscle differentiation in the Atlantic herring (Clupea harengus: Teleostei)

The myotomes in yolk-sac larvae of the Atlantic herring (Clupea harengus: Teleostei) contain a single layer of small-diameter superficial muscle fibres surrounding an inner mass of around 280 larger-diameter muscle fibres. The fraction of muscle fibre volume occupied by mitochondria is dependent on temperature, and in larvae reared at 8°C was 41% for the superficial fibres, and 25% for the inner muscle fibres. The inner muscle fibres of larvae share some myofibrillar proteins with adult white muscle, but contain unique isoforms of myosin heavy chains, troponin T, troponin I and myosin light chain 2. A monoclonal antibody has been produced which is specific to myosin light chain 3 (MLC3). Immunocytochemical studies have shown that the expression of MLC3 is switched off in the superficial muscle fibres at the start of metamorphosis when larvae reach 28–30 mm total length (TL). Metamorphosis to the juvenile stage is complete in fish 35–40 mm TL and is also associated with the development of gill filaments and the production of presumptive slow muscle fibres which form externally to the larval superficial muscle fibres in the region of the lateral line nerve.

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Effects of temperature and method of heat treatment on myofibrillar proteins of pork

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq121011023v ◽

2014 ◽

Vol 20 (3) ◽

pp. 407-415 ◽

Cited By ~ 6

Author(s):

Dragan Vujadinovic ◽

Radoslav Grujic ◽

Vladimir Tomovic ◽

Aleksandra Torbica

Keyword(s):

Heat Treatment ◽

Light Chain ◽

Myosin Light Chain ◽

Troponin I ◽

Troponin T ◽

Protein S ◽

Treatment Temperature ◽

M Protein ◽

Meat Sample ◽

Myofibrillar Proteins

During the tests in this paper, meat processing was carried out at different temperatures between the range of 51?C to 100?C. The meat was processed by dry heat (roasting) and wet heat treatments (cooking) in water at atmospheric pressure. After heat treatment, myofibrillar proteins were extracted from solutions at constant ionic strength. Quantitative and qualitative determinations of protein?s fractions were performed by capillary electrophoresis. Myofibrillar proteins were also analized for fresh pork meat sample. Results obtained in fresh meat were compared with those recorded after roasting and cooking. In the fresh and thermally processed pork the following proteins were identified: myosin, light chain 3; myosin, light chain 2; troponin - C; troponin - I; myosin, light chain 1; tropomyosin; troponin - T; actin; desmin; ? - actinin; C - protein; M - protein (M?); M - protein (M?); heavy meromyosin - HMM. For both methods of thermal processing, with increasing heat treatment temperature, concentration of soluble protein in the extract decreases rapidly after 51?C. Cooking treatment had a more intense effect on the proteins change and denaturation than roasting.

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Temperature and developmental plasticity of muscle phenotype in herring larvae

Journal of Experimental Biology ◽

10.1242/jeb.200.5.849 ◽

1997 ◽

Vol 200 (5) ◽

pp. 849-868 ◽

Cited By ~ 4

Author(s):

I A Johnston ◽

N J Cole ◽

V L A Vieira ◽

I Davidson

Keyword(s):

Developmental Plasticity ◽

Troponin I ◽

Troponin T ◽

Clupea Harengus ◽

Protein Isoforms ◽

Muscle Fibres ◽

Larval Stages ◽

Somite Stage ◽

Horizontal Septum ◽

Red Muscle

Myogenesis, the expression of myofibrillar protein isoforms and the development of muscle innervation were investigated in Clyde herring (Clupea harengus L.) in two successive spawning seasons at temperatures ranging from 5 °C to 15 °C. Myotube formation occurred in a rostral to caudal progression at similar somite stages at all temperatures. Superficial mononuclear muscle pioneer fibres were present at the horizontal septum. Myofibrillogenesis was retarded with respect to somite stage at low temperatures; for example, by the 50-somite stage, myofibrils were observed in the muscle pioneers of the first 31 somites at 12 °C, but only the first 20 somites at 5 °C. In the electron microscope, the earliest stages of myofibril assembly were observed in the muscle pioneer cells and in a proportion of the multinucleated myotubes within the same somite. By the end of somitogenesis, the density of myofibrils in the rostral myotomes was much higher at 15 °C than at 5 °C. Embryonic isoforms of myosin light chain 2 (LC2), troponin I and troponin T were identified in the presumptive white muscle using two-dimensional gel electrophoresis. Expression of the embryonic isoforms was gradually switched off during the larval stages. The size range over which embryonic isoforms were present was inversely related to rearing temperature. For example, the adult pattern of myosin LC2 expression was established at 11 mm total length (TL) at 15 °C, but not until 15 mm TL at 5 °C. Acetylcholinesterase staining was apparent at the myosepta in 31-somite stage embryos at 15 °C, but not until approximately the 40-somite stage at 5 °C. The red muscle fibres of larvae were initially innervated only at their myoseptal ends. The temperature at which the red muscle fibres became multiply innervated was inversely related to body size, occurring at 1214 mm at 12 °C, but not until 1619 mm at 5 °C. We conclude that the temperature during early development determines the relative timing and degree of expression of the myogenic programme, resulting in significant phenotypic variation in the swimming muscles of the larval stages. Our results highlight a potential mechanism whereby early thermal experience could influence survival and hence the strength of particular year classes of fish.

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Protein kinase C enhances myosin light-chain kinase effects on force development and ATPase activity in rat single skinned cardiac cells

Biochemical Journal ◽

10.1042/bj2850311 ◽

1992 ◽

Vol 285 (1) ◽

pp. 311-317 ◽

Cited By ~ 65

Author(s):

O Clement ◽

M Puceat ◽

M P Walsh ◽

G Vassort

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Atpase Activity ◽

Light Chain ◽

Myosin Light Chain Kinase ◽

Myosin Light Chain ◽

Troponin I ◽

Troponin T ◽

Cardiac Contraction ◽

Kinase C

Many neurohormones alter the force of cardiac contraction by variations in the intracellular Ca2+ concentration. alpha 1-Adrenergic and muscarinic stimulations, rather, modify the sensitivity of contractile proteins to Ca(2+)-calmodulin-myosin light-chain kinase (MLCK) complex induces a large increase in Ca2+ sensitivity (0.14 pCa unit) of these easily accessible myofilaments. This increase is further enhanced by up to 0.19 pCa unit when protein kinase C (PKC) is added together with MLCK. Similarly, the Ca2+ ATPase activity of skinned cells in suspension is increased in the presence of MLCK and further in the presence of both kinases. 32P-labelling and SDS/PAGE show that these changes are associated with light-chain 2 (LC2) phosphorylation together with phosphorylation of troponin I and troponin T when PKC is added. Although to a smaller extent than in smooth muscle, phosphorylation of cardiac myosin LC2 may be involved in the modulation of heart contractility.

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Inter- and intra-specific variation in myosin light chain and troponin I composition in fast muscle fibres from two species of fish (genusOreochromis) which have different temperature-dependent contractile properties

Journal of Muscle Research and Cell Motility ◽

10.1007/bf01738328 ◽

1991 ◽

Vol 12 (5) ◽

pp. 439-446 ◽

Cited By ~ 7

Author(s):

T. Crockford ◽

K. E. Wommack ◽

I. A. Johnston ◽

B. J. McAndrew ◽

G. Mutungi ◽

...

Keyword(s):

Light Chain ◽

Myosin Light Chain ◽

Troponin I ◽

Contractile Properties ◽

Fast Muscle ◽

Muscle Fibres ◽

Temperature Dependent ◽

Specific Variation

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Abstract P219: Differences in Phosphoproteins in Rodent versus Human Hearts: Implications for Translational Studies of Hypertensive Heart Disease

Hypertension ◽

10.1161/hyp.66.suppl_1.p219 ◽

2015 ◽

Vol 66 (suppl_1) ◽

Author(s):

Robert S Danziger ◽

Kumar Kotlo ◽

Allen Samarel ◽

Hua Chen ◽

Jared Aldstadt

Keyword(s):

Heart Disease ◽

Light Chain ◽

Myosin Light Chain ◽

Troponin T ◽

Hypertensive Heart Disease ◽

Left Ventricular ◽

Current Evidence ◽

Tissue Samples ◽

Pixel Intensity ◽

Translational Studies

Background: Rodent models are commonly used to study hypertensive heart disease. Several recent studies have probed the level of correlation between specific signaling pathways and proteins in human and rodents. Current evidence is overwhelming that protein phosphorylations play a key role in cardiac remodeling. Methods: Left ventricular tissue samples were obtained from human systolic failing (n=5) and control (n=5) hearts and 3 rat models of hypertensive heart failure (aortic banding, Dahl salt-sensitive, and spontaneously hypertensive rats (SHR)) and corresponding controls. Total proteins were extracted and and phosphoenrichment performed. Phosphoproteins were separated by 2D-DIGE with Cydye staining. Gel images were registered and rectified for composite analysis and statistical comparisons using pixel intensity. Phosphoproteins were identified by MALDI-TOF/TOF Mass Spectrometry. Results: The patterns of overall protein abundance from normal and failing hearts were not statistically different. However, when the composite of human hearts were compared with composite patterns of phosphoproteins in normal and failing rodent hearts, there were profound differences in the phosphoprotein patterns in 26% of pixels in registered images (P < 0.05). Targeted pair wise analyses showed differences (P < 0.05) between human and rodent hearts for troponin T, myosin light chain, peroxiredoxin, and haptoglobin phosphorylations. Conclusions: Together, the present results indicate significant differences in cardiac phosphoproteins in human versus rodent heart and the importance of confirming findings from rodent studies in humans for translational studies of kinases, phosphatases, and phosphoproteins. This may specifically relate to studies of phosphorylation of myosin light chain and troponin.

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Morphometry and muscle gene expression in hypertrophied hearts from polyomavirus large T antigen transgenic mice

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1995.269.1.h86 ◽

1995 ◽

Vol 269 (1) ◽

pp. H86-H95 ◽

Cited By ~ 1

Author(s):

E. Holder ◽

B. Mitmaker ◽

L. Alpert ◽

L. Chalifour

Keyword(s):

Transgenic Mice ◽

Myosin Heavy Chain ◽

Heavy Chain ◽

Light Chain ◽

Myosin Light Chain ◽

Troponin I ◽

T Antigen ◽

Large T Antigen ◽

Cross Sectional

Transgenic mice expressing polyomavirus large T antigen (PVLT) in cardiomyocytes develop a cardiac hypertrophy in adulthood. Morphometric analysis identified cardiomyocytes enlarged up to ninefold in cross-sectional area in the adult transgenic hearts compared with normal age-matched nontransgenic hearts. Most enlarged cardiomyocytes were found in the subendocardium, whereas normal-sized cardiomyocytes were localized to the midmyocardium. Transgenic hearts did not express detectable skeletal muscle actin mRNA or protein, or skeletal troponin I isoform mRNA. Some, but not all, transgenic hearts expressed an increase in the beta-myosin heavy chain mRNA. All five transgenic mice tested had increased expression of atrial natriuretic factor (ANF) mRNA. Whereas normal hearts expressed three myosin light chain proteins of 19, 16, and 15 kDa, we found that the 19-kDa myosin light chain was not observed in the transgenic hearts. We conclude that adult, PVLT-expressing, transgenic mice developed enlarged cardiomyocytes with an increase in beta-myosin heavy chain and ANF mRNA expression, but a widespread skeletal isoform usage was not present in these transgenic mice. The adult transgenic hearts thus display histological and molecular changes similar to those found in hypertrophy induced by a pressure overload in vivo.

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