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E Jaimovich

Publications and source records attributed to E Jaimovich.

At least 19 recordsLinked to original sources
PubMed2005

Capacitative calcium entry in testosterone-induced intracellular calcium oscillations in myotubes.

Ca2+ oscillations are one of the most important signals within the cell. The mechanism for generation of Ca2+ oscillations is still not yet fully elucidated. We studied the role of capacitative Ca2+ entry (CCE) on intracellular Ca2+ oscillations induced by testosterone at the single-cell level in primary myotubes. Testosterone (100 nM) rapidly induced an intracellular Ca2+ rise, accompanied by Ca2+ oscillations in a majority of myotubes. Spectral analysis of the Ca2+ oscillations revealed a periodicity of 20.3 +/- 1.8 s (frequency of 49.3 +/- 4.4 mHz). In Ca(2+)-free medium, an increase in intracellular Ca2+ was still observed, but no oscillations. Neither nifedipine nor ryanodine affected the testosterone-induced Ca2+ response. This intracellular Ca2+ release was previously shown in myotubes to be dependent on inositol-1,4,5-trisphosphate (IP3). Intracellular Ca2+ store depletion in Ca(2+)-free medium, using a sarcoplasmic/endoplasmic reticulum calcium ATPase-pump inhibitor, followed by re-addition of extracellular Ca2+, gave a fast rise in intracellular Ca2+, indicating that CCE was present in these myotubes. Application of either testosterone or albumin-bound testosterone induced Ca2+ release and led to CCE after re-addition of Ca2+ to Ca(2+)-free extracellular medium. The CCE blockers 2-aminoethyl diphenylborate and La3+, as well as perturbation of the cytoskeleton by cytochalasin D, inhibited testosterone-induced Ca2+ oscillations and CCE. The steady increase in Ca2+ induced by testosterone was not, however, affected by either La3+ or cytochalasin D. These results demonstrate testosterone-induced Ca2+ oscillations in myotubes, mediated by the interplay of IP3-sensitive Ca2+ stores and Ca2+ influx through CCE.

Animals↗
PubMed2004

IGF-I and insulin induce different intracellular calcium signals in skeletal muscle cells.

We studied the effect of IGF-I and insulin on intracellular Ca(2+) in primary cultured myotubes. IGF-I induced a fast and transient Ca(2+) increase, measured as fluo-3 fluorescence. This response was blocked by both genistein and AG538. IGF-I induced a fast inositol-1,4,5-trisphosphate (IP(3)) increase, kinetically similar to the Ca(2+) rise. The Ca(2+) signal was blocked by inhibitors of the IP(3) pathway. On the other hand, insulin produced a fast (<1 s) and transient Ca(2+) increase. Insulin-induced Ca(2+) increase was blocked in Ca(2+)-free medium and by either nifedipine or ryanodine. In the normal muscle NLT cell line, the Ca(2+ )signals induced by both hormones resemble those of primary myotubes. GLT cells, lacking the alpha1-subunit of dihydropyridine receptor (DHPR), responded to IGF-I but not to insulin, while GLT cells transfected with the alpha1-subunit of DHPR reacted to both hormones. Moreover, dyspedic muscle cells, lacking ryanodine receptors, responded to IGF-I as NLT cells, however they show no insulin-induced calcium increase. Moreover, G-protein inhibitors, pertussis toxin (PTX) and GDPbetaS, blocked the insulin-induced Ca(2+) increase without major modification of the response to IGF-I. The different intracellular Ca(2+) patterns produced by IGF-I and insulin may improve our understanding of the early action mechanisms for these hormones in skeletal muscle cells.

Animals↗
PubMed2001

Low threshold T-type calcium current in rat embryonic chromaffin cells.

1. The gating kinetics and functions of low threshold T-type current in cultured chromaffin cells from rats of 19-20 days gestation (E19-E20) were studied using the patch clamp technique. Exocytosis induced by calcium currents was monitored by the measurement of membrane capacitance and amperometry with a carbon fibre sensor. 2. In cells cultured for 1-4 days, the embryonic chromaffin cells were immunohistochemically identified by using polyclonal antibodies against dopamine beta-hydroxylase (DBH) and syntaxin. The immuno-positive cells could be separated into three types, based on the recorded calcium current properties. Type I cells showed exclusively large low threshold T-type current, Type II cells showed only high voltage activated (HVA) calcium channel current and Type III cells showed both T-type and HVA currents. These cells represented 44 %, 46 % and 10 % of the total, respectively. 3. T-type current recorded in Type I cells became detectable at -50 mV, reached its maximum amplitude of 6.8 +/- 1.2 pA pF(-1) (n = 5) at -10 mV and reversed around +50 mV. The current was characterized by criss-crossing kinetics within the -50 to -30 mV voltage range and a slow deactivation (deactivation time constant, tau(d) = 2 ms at -80 mV). The channel closing and inactivation process included both voltage-dependent and voltage-independent steps. The antihypertensive drug mibefradil (200 nM) reduced the current amplitude to about 65 % of control values. Ni(2+) also blocked the current in a dose-dependent manner with an IC(50) of 25 microM. 4. T-type current in Type I cells did not induce exocytosis, while catecholamine secretion by exocytosis could be induced by HVA calcium current in both Type II and Type III cells. The failure to induce exocytosis by T-type current in Type I cells was not due to insufficient Ca(2+) influx through the T-type calcium channel. 5. We suggest that T-type current is expressed in developing immature chromaffin cells. The T-type current is replaced progressively by HVA calcium current during pre- and post-natal development accompanying the functional maturation of the exocytosis mechanism.

Animals↗
PubMed2001

Calcium transients in 1B5 myotubes lacking ryanodine receptors are related to inositol trisphosphate receptors.

Potassium depolarization of skeletal myotubes evokes slow calcium waves that are unrelated to contraction and involve the cell nucleus (Jaimovich, E., Reyes, R., Liberona, J. L., and Powell, J. A. (2000) Am. J. Physiol. 278, C998-C1010). Studies were done in both the 1B5 (Ry53-/-) murine "dyspedic" myoblast cell line, which does not express any ryanodine receptor isoforms (Moore, R. A., Nguyen, H., Galceran, J., Pessah, I. N., and Allen, P. D. (1998) J. Cell Biol. 140, 843-851), and C(2)C(12) cells, a myoblast cell line that expresses all three isoforms. Although 1B5 cells lack ryanodine binding, they bind tritiated inositol (1,4,5)-trisphosphate. Both type 1 and type 3 inositol trisphosphate receptors were immuno-located in the nuclei of both cell types and were visualized by Western blot analysis. After stimulation with 47 mm K(+), inositol trisphosphate mass raised transiently in both cell types. Both fast calcium increase and slow propagated calcium signals were seen in C(2)C(12) myotubes. However, 1B5 myotubes (as well as ryanodine-treated C(2)C(12) myotubes) displayed only a long-lasting, non-propagating calcium increase, particularly evident in the nuclei. Calcium signals in 1B5 myotubes were almost completely blocked by inhibitors of the inositol trisphosphate pathway: U73122, 2-aminoethoxydiphenyl borate, or xestospongin C. Results support the hypothesis that inositol trisphosphate mediates slow calcium signals in muscle cell ryanodine receptors, having a role in their time course and propagation.

Animals↗
PubMed2001

IP(3) receptor function and localization in myotubes: an unexplored Ca(2+) signaling pathway in skeletal muscle.

We present evidence for an unexplored inositol 1,4,5-trisphosphate-mediated Ca(2+) signaling pathway in skeletal muscle. RT-PCR methods confirm expression of all three known isotypes of the inositol trisphosphate receptor in cultured rodent muscle. Confocal microscopy of cultured mouse muscle, doubly labeled for inositol receptor type 1 and proteins of known distribution, reveals that the receptors are localized to the I band of the sarcoplasmic reticulum, and this staining is continuous with staining of the nuclear envelope region. These results suggest that the receptors are positioned to mediate a slowly propagating Ca(2+) wave that follows the fast Ca(2+) transient upon K(+) depolarization. This slow wave, imaged using fluo-3, resulted in an increase in nucleoplasmic Ca(2+) lasting tens of seconds, but not contraction; the slow wave was blocked by both the inositol trisphosphate receptor inhibitor 2-aminoethoxydiphenyl borate and the phospholipase C inhibitor U-73122. To test the hypothesis that these slow Ca(2+) signals are involved in signal cascades leading to regulation of gene expression, we assayed for early effects of K(+) depolarization on mitogen-activated protein kinases, specifically extracellular-signal related kinases 1 and 2 and the transcription factor cAMP response element-binding protein (CREB). Within 30-60 seconds following depolarization, phosphorylation of both the kinases and CREB was evident and could be inhibited by 2-aminoethoxydiphenyl borate. These results suggest a signaling system mediated by Ca(2+) and inositol trisphosphate that could regulate gene expression in muscle cells.

Actinin↗
PubMed2000

IP(3) receptors, IP(3) transients, and nucleus-associated Ca(2+) signals in cultured skeletal muscle.

Inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)R) and ryanodine receptors (RyR) were localized in cultured rodent muscle fractions by binding of radiolabeled ligands (IP(3) and ryanodine), and IP(3)R were visualized in situ by fluorescence immunocytological techniques. Also explored was the effect of K(+) depolarization on IP(3) mass and Ca(2+) transients studied using a radio-receptor displacement assay and fluorescence imaging of intracellular fluo 3. RyR were located in a microsomal fraction; IP(3)R were preferentially found in the nuclear fraction. Fluorescence associated with anti-IP(3)R antibody was found in the region of the nuclear envelope and in a striated pattern in the sarcoplasmic areas. An increase in external K(+) affected membrane potential and produced an IP(3) transient. Rat myotubes displayed a fast-propagating Ca(2+) signal, corresponding to the excitation-contraction coupling transient and a much slower Ca(2+) wave. Both signals were triggered by high external K(+) and were independent of external Ca(2+). Slow waves were associated with cell nuclei and were propagated leaving "glowing" nuclei behind. Different roles are proposed for at least two types of Ca(2+) release channels, each mediating an intracellular signal in cultured skeletal muscle.

Amino Acid Sequence↗
PubMed2000

Aldosterone- and testosterone-mediated intracellular calcium response in skeletal muscle cell cultures.

Fast nongenomic steroid actions in several cell types seem to be mediated by second messengers such as intracellular calcium ([Ca(2+)](i)) and inositol 1,4,5-trisphosphate (IP(3)). We have shown the presence of both slow calcium transients and IP(3) receptors associated with cell nuclei in cultured skeletal muscle cells. The effect of steroids on [Ca(2+)](i) was monitored in Fluo 3-acetoxymethyl ester-loaded myotubes by either confocal microscopy or fluorescence microscopy, with the use of out-of-focus fluorescence elimination. The mass of IP(3) was determined by radioreceptor displacement assay. [Ca(2+)](i) changes after either aldosterone (10-100 nM) or testosterone (50-100 nM) were observed; a relatively fast (<2 min) calcium transient, frequently accompanied by oscillations, was evident with both hormones. A slow rise in [Ca(2+)](i) that reached its maximum after a 30-min exposure to aldosterone was also observed. Calcium responses seem to be fairly specific for aldosterone and testosterone, because several other steroid hormones do not induce detectable changes in fluorescence, even at 100-fold higher concentrations. The mass of IP(3) increased transiently to reach two- to threefold the basal level 45 s after addition of either aldosterone or testosterone, and the IP(3) transient was more rapid than the fast calcium signal. Spironolactone, an inhibitor of the intracellular aldosterone receptor, or cyproterone acetate, an inhibitor of the testosterone receptor, had no effect on the fast [Ca(2+)](i) signal or in the increase in IP(3) mass. These signals could mean that there are distinct nongenomic pathways for the action of these two steroids in skeletal muscle cells.

Aldosterone↗
PubMed1998

Differences in both inositol 1,4,5-trisphosphate mass and inositol 1,4,5-trisphosphate receptors between normal and dystrophic skeletal muscle cell lines.

Human normal (RCMH) and Duchenne muscular dystrophy (RCDMD) cell lines, as well as newly developed normal and dystrophic murine cell lines, were used for the study of both changes in inositol 1,4,5-trisphosphate (IP3) mass and IP3 binding to receptors. Basal levels of IP3 were increased two- to threefold in dystrophic human and murine cell lines compared to normal cell lines. Potassium depolarization induced a time-dependent IP3 rise in normal human cells and cells of the myogenic mouse cell line (129CB3), which returned to their basal levels after 60 s. However, in the human dystrophic cell line (RCDMD), IP3 levels remained high up to 200 s after potassium depolarization. Expression of IP3 receptors was studied measuring specific binding of 3H-IP3 in the murine cell lines (normal 129CB3 and dystrophic mdx XLT 4-2). All the cell lines bind 3H-IP3 with relatively high affinity (Kd: between 40 and 100 nmol/L). IP3 receptors are concentrated in the nuclear fraction, and their density is significantly higher in dystrophic cells compared to normal. These findings together with high basal levels of IP3 mass suggest a possible role for this system in the deficiency of intracellular calcium regulation in Duchenne muscular dystrophy.

Actinin↗
PubMed1997

Changes in IP3 metabolism during skeletal muscle development in vivo and in vitro.

We have investigated whether IP3 metabolism presents particular changes during critical stages of muscle development. With this aim, we have measured IP3 formation through phospholipase C activity, IP3 removal through IP3 5-phosphatase and IP3 3-kinase activities, as well as IP3 mass, during myogenesis in vivo and in vitro. In developing rat skeletal muscle, both IP3 3-kinase and 5-phosphatase activities were relatively constant from embryonary day 15, the earliest age studied to postnatal day 10; 5-phosphatase decreased upon further development. A transient, major increase in phospholipase C activity was evident at embryonary day 18 while a non-significant increase in IP3 mass was detected at this embrionary age. In rat skeletal muscle in primary culture, all enzyme activities as well as the mass of IP3 increased significantly in myotubes compared to myoblasts. Myotubes incubated with calcitonin gene-related peptide, responded with a transient increase in IP3 mass after 2 to 10 sec; the CGRP-induced increase being completely blocked by U-73122, a phospholipase C inhibitor. Furthermore, IP3 mass increased within 1 hr after exposure to differentiating agents of both RCMH cells, a line derived from normal human skeletal muscle, and C2C12 cells. These results indicate that changes in IP3 metabolism can be correlated to critical stages of muscle development and differentiation, suggesting a possible role for IP3 in these processes.

Animals↗
PubMed1997

Expression of ion channels during differentiation of a human skeletal muscle cell line.

An immortal, cloned cell line (RCMH), obtained from human skeletal muscle was established in our laboratory and shown to express muscle specific proteins. We measured ligand binding to ion channels, ion currents using whole cell patch clamp and intracellular calcium both in cells grown in complete media and in cells grown for 4-40 days in media supplemented with hormones and nutrients (differentiating media). Markers for differentiated muscle, such as the muscle isoform of creatine kinase and the cytoskeletal proteins alpha-actinin, alpha-sarcomeric actin, myosin and titin were present in early stages. Receptors for gamma toxin from Tityus serrulatus scorpion venom, a specific modulator for voltage dependent sodium channels, were present (0.9-1.0 pmol mg-1 protein) during stage 1 (0-6 days in culture with differentiating media) and increased by 50% in stage 3 (more than 10 days in differentiating media). High and low affinity dihydropyridine receptors present in stage 1 convert into a single type of high affinity receptors in stage 3. Both intracellular calcium release and InsP3 receptors were evident in stage 1 but ryanodine receptors were expressed only in stage 3. RCMH cells showed no voltage sensitive currents in stage 1. Between 7 and 10 days in differentiating media (stage 2), an outward potassium current was observed. Small inward currents appeared only in stage 3; we identified both tetrodotoxin sensitive and tetrodotoxin resistant sodium currents as well as calcium currents. This pattern is consistent with the expression of voltage dependent calcium release before appearance of both the action potential and ryanodine receptors.

Biomarkers↗
PubMed1996

Functional muscarinic receptors in cultured skeletal muscle.

We studied the influence of muscarinic and nicotinic stimulation on both phosphoinositide metabolism and intracellular calcium levels in rat skeletal muscle primary cultures. Both nicotine and muscarine induced an increase in cytosolic calcium measured by fluo 3 fluorescence in confocal microscopy. The mass of inositol (1,4,5)trisphosphate measured by radioreceptor assay rose 2- to 3.5-fold upon carbachol, nicotine, or muscarine stimulation. The muscarine effect was mimicked by oxotremorine-M; pirenzepine prevented the muscarine-induced inositol (1,4,5)trisphosphate increase, whereas 4-diphenylacetoxy-N-methyl piperidine methiodide was ineffective. A relatively small (40 fmol/mg protein) high-affinity 3-quinuclidinylbenzilate binding to rat myotube microsomes was consistent with the muscarinic effect found. On the other hand, the effect of nicotine on the mass of inositol (1,4,5)trisphosphate was totally suppressed in sodium-free medium. Expression of Ml muscarinic receptors coupled to phospholipase C and to internal calcium stores in cultured skeletal muscle is proposed; nicotinic receptors could be acting via ion fluxes and membrane depolarization.

Animals↗
PubMed1995

Voltage control of calcium transients elicited by caffeine and tetracaine in cultured rat muscle cells.

Cultured hind limb skeletal muscle cells from newborn rats were used to study the effect of caffeine and tetracaine upon intracellular Ca2+ release under voltage or current clamp conditions. Free [Ca2+]i was measured using the fluorescent calcium-sensitive dye Fluo-3. A field containing one or several myotubes was observed with a video camera and image analysis of fluorescence changes was performed. Addition of 100-500 microM tetracaine to the external saline elicited strong fluorescence responses in non-clamped cells, but significantly lower responses in cells clamped at -90 mV. At the same time, tetracaine inhibited voltage induced calcium release. Voltage and tetracaine modulation over the action of caffeine (500 microM) was also observed. Pretreatment of cells with 10 microM nifedipine abolished the caffeine induced fluorescence response in non-clamped cells. These findings suggest that, in cultured muscle cells, calcium release through the caffeine and tetracaine sensitive pathways is controlled by both membrane potential and the dihydropyridine receptor.

Animals↗
PubMed1994

Ion channels in a skeletal muscle cell line from a Duchenne muscular dystrophy patient.

A cell line (RCDMD), derived from a muscle biopsy taken from a 7-year-old patient with Duchenne muscular dystrophy (DMD), was established in vitro using conditioned media from the UCHT1 thyroid cell line as described elsewhere (Biochim Biophys Acta 1992; 1134:247-255). Unlike other cell lines established by the same procedure, RCDMD cells were highly refractory to transformation and the resulting cell line grew slowly with a doubling time of approximately 72 h. Further, cells continue to grow after more than 20 doublings and 15 passages. Some of the characteristics of the cell line include lack of reaction with antidystrophin antibodies and the presence of receptors for the dihydropyridine PN200-110 (Kd) = 0.3 +/- 0.05 nmol/L and Bmax = 1.06 +/- 0.03 pmol/mg protein) and for alpha-bungarotoxin (Kd = 1.02 +/- 0.17 nmol/L and Bmax = 4.2 +/- 0.37 pmol/mg protein). Patch clamped cells in the voltage clamp configuration lack ion currents when growing in complete medium with high serum, but they can be induced to differentiate by serum deprivation and addition of hormones and trace elements. After 5 days in differentiating medium, noninactivating, delayed rectifier potassium currents are seen. At day 12, A-type, inactivating potassium currents as well as transient inward currents are seen. In conditions in which sodium and potassium currents are absent, a very fast activating and fast inactivating calcium current was evident. The cell line offers the possibility of studying cellular mechanisms in the pathophysiology of DMD.

Bungarotoxins↗
PubMed1994

Intracellular Ca2+ transients induced by high external K+ and tetracaine in cultured rat myotubes.

Cultured myotubes from rat neonatal skeletal muscle were used to measure intracellular Ca2+ concentration ([Ca2+]i) and membrane potentials (Vm) using the Indo-1 microfluorimetry method and the nystatin perforated membrane patch technique, respectively. Sudden increases in external [K+]o from 5 mM to either 22, 42 or 84 mM elicited transient elevations in [Ca2+]i from a resting level of 106.2 +/- 10.3 nM (n = 41) to peak values of 297, 409 and 454 nM, respectively. Vm changes induced by elevated [K+]o followed the Nernst equation for [K+]o. The complex Ca2+ release response induced by elevated [K+]o can be described by a minimal model involving two components with different kinetics. This analysis revealed that the extent of the Ca2+ release by the fast component bears a sigmoidal relationship with Vm (midpoint at -47.5 mV and an effective valence of 4). Furthermore, while the fast transitory component was rather insensitive to [Ca2+]o and nifedipine, the slow component was profoundly inhibited by the dihydropyridine (10 microM) both in normal and in a Ca2+ deficient medium. Tetracaine (0.05 to 2 mM), a blocker of the charge movement associated with excitation-contraction (E-C) coupling, elicited a fast elevation in [Ca2+]i followed by a rise at a constant rate to levels as high as 1-2 microM, and the changes in [Ca2+]i were readily reversible. Simultaneous measurements of Vm and [Ca2+]i suggest that the fast component is coupled to the rapid depolarization of the membrane induced by the anesthetic. We concluded that tetracaine triggers the release of Ca2+ from internal stores by at least two different mechanisms, one of which is associated with the depolarizing effects of the drug.

Animals↗
PubMed1993

Calcium fluxes, ion currents and dihydropyridine receptors in a new immortal cell line from rat heart muscle.

A cell line (RCVC) in permanent culture was developed from adult rat ventricular cells; transformation was attained by incubation with conditioned media from UCHT1, a rat thyroid cell line. Immortalized ventricular cells have a doubling time of 20 h, contact inhibition of growth, and display some muscle markers such as a high glycogen content and positive immunoreaction for myoglobin, alpha-sarcomeric actin, alpha-actinin and desmin. A microsomal fraction from these cells was shown to bind 3H-nitrendipine with a maximal capacity of 295 fmol/mg protein and an equilibrium dissociation constant of 0.7 nM. Nifedipine-sensitive 45Ca2+ influx was evident in partially depolarized cells (40 mM K+ in the incubation medium). An equivalent influx, induced by the calcium channel agonist BAYK-8644 and CGP-28392, was obtained in normally polarized cells. Patch clamp studies show slow inward currents that can be completely blocked by 5 microM nifedipine; cells were induced to further differentiation by culturing in a hormone supplemented medium for 30 days. Under this condition, fast, inactivating inward currents and a large outward current became apparent. After 40-60 days, the cells exhibit La(3+)-sensitive fast and slow inactivating inward currents that resemble T and L-type Ca2+ currents. This cell line appears to be a good model system for the investigation of cardiomyocyte differentiation in situ.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1992

A human skeletal muscle cell line obtained from an adult donor.

A cell line (RCMH) in permanent culture was established from surgically removed adult normal human skeletal muscle by exposure to conditioned media obtained from thyroid cells. Cells proliferated indefinitely but displayed density inhibition of growth while maintaining some differentiated markers. Under certain incubation conditions, cells fused into myotube-like structures, with a concomitant increase in muscle specific proteins, such as human myoglobin, skeletal muscle myosin, desmin and dystrophin, as identified using immunocytochemical procedures. In addition, RCMH cells displayed high affinity receptors for alpha-bungarotoxin (Bmax = 0.7 pmol/mg protein, Kd = 1.5 nM) and dihydropyridines (Bmax = 0.3 pmol/mg protein, Kd = 0.5 nM for [3H]PN200-110); these values are comparable to those reported for muscle cells in primary culture. Patch-clamp studies showed the presence of 42 pS carbachol gated channels and of 5 pS calcium channels (current carried by barium); chloride and potassium channels were also seen. This new cell line appears to be a convenient model system to study skeletal muscle function.

Adult↗
PubMed1991

Modulation of the activity of the transverse tubule Mg(2+)-ATPase from frog skeletal muscle by a monoclonal antibody in vitro.

We have established several hybridoma lines that produce monoclonal antibodies against transverse tubule (t-tubule) proteins from frog skeletal muscle. The specificity of these antibodies was characterized by ELISA and Western immunoblotting with purified t-tubule, sarcoplasmic reticulum and partially purified sarcolemmal membranes. One of the monoclonal antibodies (2/34.4) recognizes a band of 109,000 Da in immunoblots. When purified frog t-tubule vesicles were preincubated with this antibody we observed an increase in the rate of the Mg(2+)-ATPase enzyme (up to six fold) which was dependent on antibody concentration. Immunocytological experiments done on cryostat sections of frog muscle indicate that the antigen recognized by this antibody is localized mainly at the level of the t-tubules (I band) and to a lesser extent at the sarcolemma. These results indicate that monoclonal antibody 2/34.4 recognizes the t-tubule Mg(2+)-ATPase and modulates its activity. This antibody should be useful as a probe on studies designed to study the physiological function of the enzyme.

Animals↗