Calpain and calpastatin

Murachi, Takashi

doi:10.1016/0968-0004(83)90165-2

Cited by 307 publications

(148 citation statements)

References 16 publications

Supporting

Mentioning

143

Contrasting

Order By: Relevance

“…Properties common to catalytically active calpains from various sources have been reported to include the need for 'Ca2+ and an SH-reducing agent' (Murachi, 1983). The need for Ca2+ to be present is beyond dispute and it appears to be common practice to include also a low-molecular-mass mercaptan during purification and in reaction mixtures when catalytic activity is assayed.…”

Section: Results and Discussion Preparation Of Fully Active Activatormentioning

confidence: 99%

“…with ficin (Malthouse and Brocklehurst, 1976), papain (Shipton and Brocklehurst, 1978), actinidin (Brocklehurst et al, 1981), cathepsins B and H (Willenbrock and Brocklehurst, 1985), gingivain (Shah et al, 1991) and papaya proteinase Q (Topham et al, 1991). Characterization of calpain by using disulphide reactivity probes necessitated the establishment of an experimental protocol that takes account of the multiplicity of thiol groups in calpain, the reported demand for the presence of low-molecular-mass mercaptan for catalytic activity, the need for Ca2+ activation (Murachi, 1983), and the effect of autolysis on catalytic-site integrity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Catalytic-site characteristics of the porcine calpain II 80 kDa/18 kDa heterodimer revealed by selective reaction of its essential thiol group with two-hydronic-state time-dependent inhibitors: evidence for a catalytic site Cys/His interactive system and an ionizing modulatory group

Mellor

Sreedharan

Kowlessur

et al. 1993

Biochemical Journal

View full text Add to dashboard Cite

Activator-free 80 kDa/30 kDa heterodimer (in the absence of Ca2+) reacts relatively slowly with ethyl 2-pyridyl disulphide at pH 5.9; over 5000 s five thiol groups per molecule react, all at similar rates. In the presence of 8 mM CaCl2 under otherwise identical conditions (and also in the pH range 3.8-10.4) an initial faster phase of reaction corresponding to approx. one thiol group per molecule of heterodimer is generated, but it is not cleanly separated from the subsequent slower reactions on the stopped-flow trace. This fast phase of reaction does not occur when E64-inactivated calpain II is substituted for active 80 kDa/ 18 kDa heterodimer. 5. Greatly improved resolution of the fast phase of reaction involving the catalytic-site thiol group was achieved by using 2,2'-dipyridyl disulphide (2-Py-S-S-2-Py) instead of ethyl 2-pyridyl disulphide. 6. The pH-dependence of the second-order rate constant (k) for the reaction of the catalytically active activator-free 80 kDa/ 18 kDa calpain II heterodimer with 2-Py-S-S-2-Py was studied by stopped-flow spectral analysis in the pH range approx. 3-8 without interference from reactions of other thiol groups. 7. The form of the pH-k profile establishes for the first time the existence of an interactive catalytic site system [probably containing a (Cys)-S-/(His)-Im+H ion pairl analogous to those present in monomeric non-Ca2+-activated cysteine proteinases. 8. The reactivity and kinetically influential ionization characteristics of the calpain II 80 kDa/ 18 kDa heterodimer, which are strikingly different from those of other cysteine proteinases, are compared with those of papain, actinidin, ficin and papaya proteinase Q. 9. The possibility that in the calpain II 80 kDa/ 18 kDa heterodimer, movement of the ion-pair components might be controlled by the electrostatic influence of a carboxylate anion is discussed.

show abstract

Section: Results and Discussion Preparation Of Fully Active Activatormentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Catalytic-site characteristics of the porcine calpain II 80 kDa/18 kDa heterodimer revealed by selective reaction of its essential thiol group with two-hydronic-state time-dependent inhibitors: evidence for a catalytic site Cys/His interactive system and an ionizing modulatory group

Mellor

Sreedharan

Kowlessur

et al. 1993

Biochemical Journal

View full text Add to dashboard Cite

show abstract

“…Attention has been increasingly paid to Ca2+-dependent thiol proteases, calpains, that are present widely in most tissues, in the hope that this family of enzymes may have some functions in the control of various Ca2+-mediated cellular processes, particularly in stimulus-response coupling [5]. Calpains from many tissues are located principally in the cytosol, and show a molecular mass of approx.…”

Section: Discussionmentioning

confidence: 99%

“…Since a class of calpains sensitive to the micromolar range of Ca2+ (calpain I) are known to occur in most tissues [5,14-l 81 including bovine brain cytosol [ 131, attempts have been made to clarify their role in many Ca2+-mediated physiological processes. Although an inhibitor protein (calpastatin) specific to calpain has been characterized from mammalian tissues [5,19], little This paper is dedicated to Professor S.P. Datta * Present address: Department of Surgery, Kobe University School of Medicine, Kobe 650, Japan + Present address: Department of Anesthesiology, Kobe University School of Medicine, Kobe 650, Japan is known about the activator of this family of enzymes.…”

Section: Introductionmentioning

confidence: 99%

A calcium‐protease activator associated with brain microsomal‐insoluble elements

et al. 1986

View full text Add to dashboard Cite

A factor which markedly activates Caz+-dependent thiol protease (calpain) is associated with Triton X-lOOinsoluble materials, presumably structural elements such as cytoskeletons, of bovine brain microsomal fraction. This factor is extracted with 0.6 M KCl, and purified partially by sucrose density gradient centrifugation and hydroxyapatite column chromatography. The factor appears to be a heat-stable protein with an approximate M, of 15 000. With casein as substrate this factor activates both calpain I and calpain II severalfold up to more than lo-fold without alteration of their affinity to Ca 2+. Calmodulin is unable to substitute for this factor. A similar factor is associated with human platelet insoluble materials. Calpain Calpain activator Protease

show abstract

“…This has been shown to be a pivotal event in myocardial cell injury and results in the activation of intracellular Ca 2+ -dependent enzymes. Calpains, a family of Ca 2+ -activated proteases found in the cytosol of many cell types (Murachi, 1983), have been implicated in a wide array of cellular pathological states associated with proteolysis and cell death. However, their precise function during myocardial ischaemia still remains to be established.…”

Section: Introductionmentioning

confidence: 99%

Activity profile of calpains I and II in chronically infarcted rat myocardium – influence of the calpain inhibitor CAL 9961

Sandmann

Prenzel

Shaw

et al. 2002

British J Pharmacology

View full text Add to dashboard Cite

1 The calpains have been proposed to be activated following cardiac ischaemia and to contribute to myocyte damage after myocardial infarction (MI). In this study, the activity of calpains I and II in the infarcted and non-infarcted rat myocardium and the action of the selective calpain inhibitor, CAL 9961, has been investigated. 2 MI was induced by permanent ligation of the left coronary artery. One, 3, 7 and 14 days post MI, the enzymes calpain I and II were separated from homogenates of the interventricular septum (IS) and left ventricular free wall (LVFW) by chromatography on DEAE-Sepharose. The activity of the calpains was measured in sham-operated and MI animals chronically treated with placebo or CAL 9961 (15 mg kg 71 d 71 s.c.) in a synthetic substrate assay. Treatment was started 3 days before MI induction. 3 Calpain I activity reached highest values in IS 14 days post MI, whereas maximum activity of calpain II was measured in LVFW 3 days post MI. In experiments in vitro, CAL 9961 completely inhibited both calpains. In vivo, chronic treatment of MI animals with CAL 9961 partially prevented the increase in calpain I activity in IS and reduced calpain II activity in LVFW to sham levels. 4 Our ®ndings demonstrate that calpains I and II are activated after MI, however, both enzymes di er in their regional and temporal activation within the infarcted myocardium. Chronic inhibition of these enzymes with CAL 9961 might limit the calpain-induced myocardial damage and preserve cardiac structural integrity post MI.

show abstract

Calpain and calpastatin

Cited by 307 publications

References 16 publications

Catalytic-site characteristics of the porcine calpain II 80 kDa/18 kDa heterodimer revealed by selective reaction of its essential thiol group with two-hydronic-state time-dependent inhibitors: evidence for a catalytic site Cys/His interactive system and an ionizing modulatory group

Catalytic-site characteristics of the porcine calpain II 80 kDa/18 kDa heterodimer revealed by selective reaction of its essential thiol group with two-hydronic-state time-dependent inhibitors: evidence for a catalytic site Cys/His interactive system and an ionizing modulatory group

A calcium‐protease activator associated with brain microsomal‐insoluble elements

Activity profile of calpains I and II in chronically infarcted rat myocardium – influence of the calpain inhibitor CAL 9961

Contact Info

Product

Resources

About