a monoclonal antibody that recognizes different conformational states of skeletal muscle troponin c and other calcium binding proteins. | skeletal muscle troponin c contains four ca(2+)-binding sites, two with a high affinity for ca2+ that also bind mg2+ competitively (ca2+/mg2+ sites) and two sites of lower affinity that are specific for ca2+. we have characterized a monoclonal antibody (b9d9) that was produced against rabbit skeletal troponin c. the binding of this antibody to rabbit skeletal troponin c is sensitive to the binding of ca2+. increasing the ca2+ concentration produces a decrease in the amount of antibody bound with ... | 1992 | 1527217 |
functional characterization of the two isoforms of troponin c from the arthropod balanus nubilus. | two isoforms of troponin c (btnc1 and btnc2) from the striated muscle of the arthropod balanus nubilus darwin (giant barnacle) have been purified (potter et al., 1987; collins et al., 1991). both isoforms were present in all of the white striated muscle fibres studied but not in the red fibres. the ratio of btnc2 to btnc1 in different fibre types varied between 3:1 and 1:1. both forms of tnc could be readily extracted from myofibrillar bundles of barnacle muscle in low ionic strength edta soluti ... | 1991 | 1791193 |
amino acid sequences and ca2(+)-binding properties of two isoforms of barnacle troponin c. | much of our knowledge of the relationship between elevation of free sarcoplasmic [ca2+] and skeletal muscle contraction has come from physiological studies on barnacle muscle fibers. little is known, however, about the biochemical properties of the barnacle proteins responsible for ca2+ regulation. in order to help rectify this unfortunate situation, we purified the two major isoforms (btnc1 and btnc2) of troponin c (tnc) from the giant barnacle, balanus nubilis, and determined their amino acid ... | 1991 | 1988057 |
expression of a mammalian na-h exchanger in muscle fibres of the giant barnacle. | it is now well established that the internal ph (phi) of mammalian cells is regulated by means of a plasma membrane transport system that exchanges extracellular na+ for intracellular h+ (ref. 1). furthermore, modulation of the activity of the na-h exchanger seems to have a crucial role in the action of various mitogens and growth factors. the possibility that such a mammalian na-h exchanger might be efficiently expressed in a giant invertebrate cell was suggested to us by recent results of barn ... | 1985 | 2409448 |
characterization of troponin-c interactions in skinned barnacle muscle: comparison with troponin-c from rabbit striated muscle. | previously it was shown that when troponin-c (tnc) is extracted from barnacle myofibrillar bundles they lose their ca2+ sensitivity, which can be restored by adding back barnacle tnc (either isoform, btnc1 or btnc2). thus barnacle muscle shows thin filament regulation, as does rabbit psoas skeletal muscle. in this paper we compare the interactions of barnacle and rabbit fast muscle tnc in their respective muscles. we demonstrate that muscle fibres from the giant barnacle, balanus nubilus, contai ... | 1997 | 9429158 |
zinc content, metal chelator inactivation and catalytic inhibition of d-lactate dehydrogenase from the barnacle, balanus nubilus darwin. | | 1998 | 104663 |
mode of stimulation by adenosine 3':5'-cyclic monophosphate of the sodium efflux in barnacle muscle fibres. | 1. giant fibres of the barnacle balanus nubilus have been used as a preparation for studying the mode of action of camp on sodium transport. 2. it is shown that a concentration of camp as low as 10(-6)m, when micro-injected, causes a sharp rise in the radio-na efflux. ouabain fails to reverse the camp effect. 3. the magnitude of the response of the na efflux to camp is markedly reduced by pre-injecting 100 or 500 mm-egta solutions or by omitting ca2+ from the bathing medium. both together fail t ... | 2003 | 181561 |
calcium influxes and tension development in perfused single barnacle muscle fibres under membrane potential control. | 1. single giant barnacle muscle fibres from megabalanus psittacus (darwin) were used to measure the ca entry and the development of tension in the fibres under membrane potential control.2. fibres bathing in 60 mm-mgcl(2) sea water, free of ca, did not develop tension with sudden displacements of the membrane potential towards more positive values. this failure to develop tension with depolarizations was observed with and without the internal application of ca buffers.3. fibres bathing in artifi ... | 2014 | 4449073 |
neural organization of shadow reflex in a giant barnacle, balanus nubilus. | | 2003 | 196057 |
evaluation of the dmo method for measuring intracellular ph. | intracellular ph in single muscle fibres from balanus nubilus was determined, both by the weak acid distribution method (using 5,5-dimethyl-2,4-oxazolidine dione) and by means of a glass ph microelectrode, following prolonged equilibrations in normal, acid or alkaline ringer solutions. in the dmo method [3h]inulin was combined with [14c]dmo so that an extracellular space could be calculated for each 'dmo space' on each fibre. less than ideal uptake curves were obtained both for [14c]dmo and [3h] ... | 1999 | 27852 |
evidence for the nonhydrophobic interaction of aromatic, nitrogen-containing compounds with the coenzyme binding site of a nad-linked d-lactate dehydrogenase. | quantitative structure activity relationships suggest that the binding of quinoline and phenanthroline analogs to d-lactate dehydrogenase from the barnacle, balanus nubilus darwin, does not involve primarily hydrophobic effects. this phenomenon appears to exist also for other lactate dehydrogenases. | 1992 | 207551 |
a study of the ouabain-insensitive sodium efflux in barnacle muscle fibres using phorbol dibutyrate as a probe. | 1. the resting ouabain-insensitive na+ efflux in muscle fibres isolated from the barnacle, balanus nubilus, is stimulated by external or internal application of phorbol 12,13-dibutyrate (pd). the response occurs fairly promptly and may not decay at all, or more commonly, decay rather slowly. the magnitude of the response to external or internal application of pd is dose-dependent, the minimum effective concentration being about 10(-8) m. 2. the response to pd fails to occur in the nominal absenc ... | 2007 | 2167970 |
transformation of signals by interneurones in the barnacle's visual pathway. | 1. the photoreceptors of the median eye of the giant barnacle drive decrementally-conducting neurones in the supraoesophageal ganglion termed ;inverting cells' (i-cells) which in turn drive impulse-producing neurones termed ;amplifying cells' (a-cells). using intracellular recording techniques we have studied the role of i-cells in visual processing.2. horseradish peroxidase injections show that i-cells are interneurones whose processes are confined to the regions of the photoreceptor terminals ... | 1981 | 6267250 |
a diazo-2 study of relaxation mechanisms in frog and barnacle muscle fibres: effects of ph, mgadp, and inorganic phosphate. | the aim of this study was to compare the effects of increased concentrations of mgadp, inorganic phosphate (pi) and h+ ([mgadp], [pi] and [h+], respectively) on the rate of relaxation in two different muscle types: skinned muscle fibres from the frog rana temporaria and myofibrillar bundles from the giant pacific acorn barnacle balanus nubilus. relaxation transients are produced by the photolysis of diazo-2 and are well fitted with a double exponential curve, giving two rate constants: k1 [5.6+/ ... | 1999 | 9929560 |
determination of resting free calcium in barnacle muscle using modified aequorins, buffered calcium injections, and simultaneous image-intensified video microscopy. | knowing the resting free calcium is important in understanding the role of calcium as an intracellular second messenger. we used a bracketing (null) technique with a luminescent calcium indicator, aequorin, microinjection and image-intensification to measure free calcium in single muscle fibres from the barnacle, balanus nubilus. we injected modified aequorins (recombinant, and hch-) which after a 30 min diffusion gave reasonable resting glows. subsequent injection of calcium (strongly buffered ... | 1995 | 8567937 |