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Du M, Li X, Zhang D, Li Z, Hou C, Ren C, Bai Y. Phosphorylation plays positive roles in regulating the inhibitory ability of calpastatin to calpain. Int J Food Sci Technol 2022. [DOI: 10.1111/ijfs.15437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Manting Du
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
- College of Food and Biological Engineering Zhengzhou University of Light Industry Zhengzhou Henan China
- Henan Key Laboratory of Cold Chain Food Quality and Safety Control Zhengzhou Henan China
| | - Xin Li
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
| | - Dequan Zhang
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
| | - Zheng Li
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
| | - Chengli Hou
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
| | - Chi Ren
- Institute of Food Science and Technology Chinese Academy of Agricultural Sciences, Key Laboratory of Agro‐products Quality & Safety in Harvest, Storage, Transportation, Management and Control, Ministry of Agriculture and Rural Affairs Beijing China
| | - Yanhong Bai
- College of Food and Biological Engineering Zhengzhou University of Light Industry Zhengzhou Henan China
- Henan Key Laboratory of Cold Chain Food Quality and Safety Control Zhengzhou Henan China
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2
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Motter MM, Corva PM, Soria LA. Expression of calpastatin isoforms in three skeletal muscles of Angus steers and their association with fiber type composition and proteolytic potential. Meat Sci 2020; 171:108267. [PMID: 32745871 DOI: 10.1016/j.meatsci.2020.108267] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 07/24/2020] [Accepted: 07/24/2020] [Indexed: 10/23/2022]
Abstract
This study aimed to evaluate the expression of calpastatin (CAST) isoforms and their potential associations with fiber type composition (%RA), calpastatin activity (CA) and myofibril fragmentation index (MFI) in three muscles with known differences in tenderness (infraspinatus, triceps brachii and semitendinosus) of Angus steers. Expression of total CAST (CAST-T) and CAST isoforms I, II, III (2-3) and III (2-4) (including or not exon 3) was evaluated by qRT-PCR. CAST expression and CA were significantly higher and MFI was lower in semitendinosus, the muscle with the highest %RA of IIX fibers. Differential expression of isoforms defined the variability in CAST-T among muscles. Semitendinosus had a higher expression of isoforms II and III (2-3), but lower expression of III (2-4) compared to the other two muscles. Relative expression of isoforms II and III that were defined by promoter preference linked to alternative splicing, seem to be the main factors explaining differences in CAST expression and ultimately in MFI among muscles.
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Affiliation(s)
- Mariana M Motter
- Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Cátedra de Genética, Chorroarín 280 (1427), Buenos Aires, Argentina
| | - Pablo M Corva
- Universidad Nacional de Mar del Plata, Facultad de Ciencias Agrarias, Unidad Integrada Balcarce, Departamento de Producción Animal, CC276 (CP7620) Balcarce, Argentina
| | - Liliana A Soria
- Universidad de Buenos Aires, Facultad de Ciencias Veterinarias, Cátedra de Genética, Chorroarín 280 (1427), Buenos Aires, Argentina.
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3
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Sparatore B, Pedrazzi M, Garuti A, Franchi A, Averna M, Ballestrero A, De Tullio R. A new human calpastatin skipped of the inhibitory region protects calpain-1 from inactivation and degradation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:1260-1271. [DOI: 10.1016/j.bbamcr.2019.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 12/20/2018] [Accepted: 01/06/2019] [Indexed: 12/17/2022]
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4
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Production and Purification of Recombinant Calpastatin. Methods Mol Biol 2019. [PMID: 30617803 DOI: 10.1007/978-1-4939-8988-1_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
Abstract
The production of recombinant calpastatin in E. coli has become an efficient tool to obtain discrete amounts of a specific calpastatin species that can be present concomitantly with other calpastatin fragments/forms in the same tissue or cell type in a given condition. Indeed, at present, it is still difficult to distinguish the various calpastatin species for several reasons among which: calpastatins differ only at the N-terminus, can undergo calpain-dependent cleavage generating discrete fragments, and show anomalous electrophoretic mobility. Another benefit of using recombinant calpastatin is that, as the wild-type forms, it is heat resistant and thus can be efficiently isolated taking advantage of a simple quick purification step. Finally, the lack of posttranslational modifications makes recombinant calpastatin species particularly suitable for studying in vitro the biochemical features of specific parts of the inhibitor that following controlled posttranslational modifications change their functional interaction with calpain. In this chapter, we describe, starting from the mRNA sequence, how to produce rat calpastatin Type I in E. coli. We use routinely the same method, with minor modifications, for the production of other calpastatin species deriving from different tissues or organisms and calpastatin constructs having only specific domains. The possibility to obtain large amounts of a single calpain inhibitor form is a great advantage for studying the calpain/calpastatin system in vitro.
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Kelley EF, Johnson BD, Snyder EM. Beta-2 Adrenergic Receptor Genotype Influences Power Output in Healthy Subjects. J Strength Cond Res 2018; 31:2053-2059. [PMID: 28557859 DOI: 10.1519/jsc.0000000000001978] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Kelley, EF, Johnson, BD, and Snyder, EM. Beta-2 adrenergic receptor genotype influences power output in healthy subjects. J Strength Cond Res 31(8): 2053-2059, 2017-The purpose of this study was to determine the effects of ADRB2 genotypes on muscle function (absolute power and relative power) in healthy subjects. We performed genotyping of the ADRB2 (amino acid 16) and high-intensity, steady-state exercise on 77 healthy subjects (AA = 18, AG = 25, GG = 34). There were no differences between genotype groups in age, height, weight, or body mass index (BMI) (age = 28.9 ± 5.7 years, 27.9 ± 5.7 years, 29.2 ± 5.9 years, height = 170.7 ± 8.6 cm, 174.9 ± 8.7 cm, 173.4 ± 9.6 cm, weight = 68.5 ± 13.0 kg, 75.0 ± 12.9 kg, 74.4 ± 12.9 kg, and BMI = 23.4 ± 3.9, 24.4 ± 2.9, 24.7 ± 3.4, for AA, AG, and GG, respectively). The genotype groups differed significantly in watts, and watts/V[Combining Dot Above]O2 with heavy exercise (watts = 186.3 ± 54.6, 237.8 ± 54.4, 219.4 ± 79.5, watts/V[Combining Dot Above]O2 = 0.08 ± 0.006, 0.09 ± 0.005, 0.08 ± 0.006). There was a trend toward significance (p = 0.058) for W·kg (2.7 ± 0.4, 3.2 ± 0.5, 2.9 ± 0.8, for AA, AG, and GG, respectively). These data suggest that genetic variation of the ADRB2 may influence relative strength in healthy subjects and may become an important genetic determinant of muscular strength and functional capacity in patients with diseases that result in a loss of muscle strength.
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Affiliation(s)
- Eli F Kelley
- 1University of Minnesota, Minneapolis, Minnesota; and 2Mayo Clinic, Rochester, Minnesota
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Pin F, Minero VG, Penna F, Muscaritoli M, De Tullio R, Baccino FM, Costelli P. Interference with Ca 2+-Dependent Proteolysis Does Not Alter the Course of Muscle Wasting in Experimental Cancer Cachexia. Front Physiol 2017; 8:213. [PMID: 28469577 PMCID: PMC5395607 DOI: 10.3389/fphys.2017.00213] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Accepted: 03/23/2017] [Indexed: 01/24/2023] Open
Abstract
Protein hypercatabolism significantly contributes to the onset and progression of muscle wasting in cancer cachexia. In this regard, a major role is played by the ATP-ubiquitin-proteasome-dependent pathway and by autophagy. However, little is known about the relevance of the Ca2+-dependent proteolytic system. Since previous results suggested that this pathway is activated in the skeletal muscle of tumor hosts, the present study was aimed to investigate whether inhibition of Ca2+-dependent proteases (calpains) may improve cancer-induced muscle wasting. Two experimental models of cancer cachexia were used, namely the AH-130 Yoshida hepatoma and the C26 colon carcinoma. The Ca2+-dependent proteolytic system was inhibited by treating the animals with dantrolene or by overexpressing in the muscle calpastatin, the physiologic inhibitor of Ca2+-dependent proteases. The results confirm that calpain-1 is overexpressed and calpastatin is reduced in the muscle of rats implanted with the AH-130 hepatoma, and show for the first time that the Ca2+-dependent proteolytic system is overactivated also in the C26-bearing mice. Yet, administration of dantrolene, an inhibitor of the Ca2+-dependent proteases, did not modify tumor-induced body weight loss and muscle wasting in the AH-130 hosts. Dantrolene was also unable to reduce the enhancement of protein degradation rates occurring in rats bearing the AH-130 hepatoma. Similarly, overexpression of calpastatin in the tibialis muscle of the C26 hosts did not improve muscle wasting at all. These observations suggest that inhibiting a single proteolytic system is not a good strategy to contrast cancer-induced muscle wasting. In this regard, a more general and integrated approach aimed at targeting the catabolic stimuli rather than the proteolytic activity of a single pathway would likely be the most appropriate therapeutic intervention.
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Affiliation(s)
- Fabrizio Pin
- Department of Clinical and Biological Sciences, University of TurinTurin, Italy
| | - Valerio G Minero
- Department of Clinical and Biological Sciences, University of TurinTurin, Italy
| | - Fabio Penna
- Department of Clinical and Biological Sciences, University of TurinTurin, Italy
| | | | - Roberta De Tullio
- Department of Experimental Medicine, University of GenovaGenova, Italy
| | - Francesco M Baccino
- Department of Clinical and Biological Sciences, University of TurinTurin, Italy
| | - Paola Costelli
- Department of Clinical and Biological Sciences, University of TurinTurin, Italy
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Calpain-1 resident in lipid raft/caveolin-1 membrane microdomains plays a protective role in endothelial cells. Biochimie 2017; 133:20-27. [DOI: 10.1016/j.biochi.2016.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 12/07/2016] [Indexed: 12/20/2022]
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8
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Averna M, De Tullio R, Pedrazzi M, Bavestrello M, Pellegrini M, Salamino F, Pontremoli S, Melloni E. Interaction between calpain-1 and HSP90: new insights into the regulation of localization and activity of the protease. PLoS One 2015; 10:e0116738. [PMID: 25575026 PMCID: PMC4289065 DOI: 10.1371/journal.pone.0116738] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/12/2014] [Indexed: 12/18/2022] Open
Abstract
Here we demonstrate that heat shock protein 90 (HSP90) interacts with calpain-1, but not with calpain-2, and forms a discrete complex in which the protease maintains its catalytic activity, although with a lower affinity for Ca2+. Equilibrium gel distribution experiments show that this complex is composed by an equal number of molecules of each protein partner. Moreover, in resting cells, cytosolic calpain-1 is completely associated with HSP90. Since calpain-1, in association with HSP90, retains its proteolytic activity, and the chaperone is displaced by calpastatin also in the absence of Ca2+, the catalytic cleft of the protease is not involved in this association. Thus, calpain-1 can form two distinct complexes depending on the availability of calpastatin in the cytosol. The occurrence of a complex between HSP90 and calpain-1, in which the protease is still activable, can prevent the complete inhibition of the protease even in the presence of high calpastatin levels. We also demonstrate that in basal cell conditions HSP90 and calpain-1, but not calpain-2, are inserted in the multi-protein N-Methyl-D-Aspartate receptor (NMDAR) complex. The amount of calpain-1 at the NMDAR cluster is not modified in conditions of increased [Ca2+]i, and this resident protease is involved in the processing of NMDAR components. Finally, the amount of calpain-1 associated with NMDAR cluster is independent from Ca2+-mediated translocation. Our findings show that HSP90 plays an important role in maintaining a given and proper amount of calpain-1 at the functional sites.
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Affiliation(s)
- Monica Averna
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Roberta De Tullio
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Marco Pedrazzi
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Margherita Bavestrello
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Matteo Pellegrini
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Franca Salamino
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Sandro Pontremoli
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
| | - Edon Melloni
- Department of Experimental Medicine (DIMES)-Biochemistry Section, and Center of Excellence for Biomedical Research (CEBR), University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
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9
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De Tullio R, Averna M, Pedrazzi M, Sparatore B, Salamino F, Pontremoli S, Melloni E. Differential regulation of the calpain-calpastatin complex by the L-domain of calpastatin. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:2583-91. [PMID: 25026177 DOI: 10.1016/j.bbamcr.2014.07.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2014] [Revised: 07/03/2014] [Accepted: 07/07/2014] [Indexed: 01/28/2023]
Abstract
Here we demonstrate that the presence of the L-domain in calpastatins induces biphasic interaction with calpain. Competition experiments revealed that the L-domain is involved in positioning the first inhibitory unit in close and correct proximity to the calpain active site cleft, both in the closed and in the open conformation. At high concentrations of calpastatin, the multiple EF-hand structures in domains IV and VI of calpain can bind calpastatin, maintaining the active site accessible to substrate. Based on these observations, we hypothesize that two distinct calpain-calpastatin complexes may occur in which calpain can be either fully inhibited (I) or fully active (II). In complex II the accessible calpain active site can be occupied by an additional calpastatin molecule, now a cleavable substrate. The consequent proteolysis promotes the accumulation of calpastatin free inhibitory units which are able of improving the capacity of the cell to inhibit calpain. This process operates under conditions of prolonged [Ca(2+)] alteration, as seen for instance in Familial Amyotrophic Lateral Sclerosis (FALS) in which calpastatin levels are increased. Our findings show that the L-domain of calpastatin plays a crucial role in determining the formation of complexes with calpain in which calpain can be either inhibited or still active. Moreover, the presence of multiple inhibitory domains in native full-length calpastatin molecules provides a reservoir of potential inhibitory units to be used to counteract aberrant calpain activity.
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Affiliation(s)
- Roberta De Tullio
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy.
| | - Monica Averna
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
| | - Marco Pedrazzi
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
| | - Bianca Sparatore
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
| | - Franca Salamino
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
| | - Sandro Pontremoli
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
| | - Edon Melloni
- Department of Experimental Medicine (DIMES), Biochemistry Section, University of Genova, Viale Benedetto XV, 1-16132 Genova, Italy; Centre of Excellence for Biomedical Research, University of Genova, Viale Benedetto XV, 7-16132 Genova, Italy
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Nuber S, Tadros D, Fields J, Overk CR, Ettle B, Kosberg K, Mante M, Rockenstein E, Trejo M, Masliah E. Environmental neurotoxic challenge of conditional alpha-synuclein transgenic mice predicts a dopaminergic olfactory-striatal interplay in early PD. Acta Neuropathol 2014; 127:477-94. [PMID: 24509835 DOI: 10.1007/s00401-014-1255-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Revised: 01/31/2014] [Accepted: 02/01/2014] [Indexed: 12/17/2022]
Abstract
The olfactory bulb (OB) is one of the first brain regions in Parkinson's disease (PD) to contain alpha-synuclein (α-syn) inclusions, possibly associated with nonmotor symptoms. Mechanisms underlying olfactory synucleinopathy, its contribution to progressive aggregation pathology and nigrostriatal dopaminergic loss observed at later stages, remain unclear. A second hit, such as environmental toxins, is suggestive for α-syn aggregation in olfactory neurons, potentially triggering disease progression. To address the possible pathogenic role of olfactory α-syn accumulation in early PD, we exposed mice with site-specific and inducible overexpression of familial PD-linked mutant α-syn in OB neurons to a low dose of the herbicide paraquat. Here, we found that olfactory α-syn per se elicited structural and behavioral abnormalities, characteristic of an early time point in models with widespread α-syn expression, including hyperactivity and increased striatal dopaminergic marker. Suppression of α-syn reversed the dopaminergic phenotype. In contrast, paraquat treatment synergistically induced degeneration of olfactory dopaminergic cells and opposed the higher reactive phenotype. Neither neurodegeneration nor behavioral abnormalities were detected in paraquat-treated mice with suppressed α-syn expression. By increasing calpain activity, paraquat induced a pathological cascade leading to inhibition of autophagy clearance and accumulation of calpain-cleaved truncated and insoluble α-syn, recapitulating biochemical and structural changes in human PD. Thus our results underscore the primary role of proteolytic failure in aggregation pathology. In addition, we provide novel evidence that olfactory dopaminergic neurons display an increased vulnerability toward neurotoxins in dependence to presence of human α-syn, possibly mediating an olfactory-striatal dopaminergic network dysfunction in mouse models and early PD.
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Affiliation(s)
- Silke Nuber
- Department of Neurosciences, University of California San Diego, 9500 Gilman Dr., MTF 344, La Jolla, CA, 92093-0624, USA,
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11
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Calvo J, Iguácel L, Kirinus J, Serrano M, Ripoll G, Casasús I, Joy M, Pérez-Velasco L, Sarto P, Albertí P, Blanco M. A new single nucleotide polymorphism in the calpastatin (CAST) gene associated with beef tenderness. Meat Sci 2014; 96:775-82. [DOI: 10.1016/j.meatsci.2013.10.003] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 09/27/2013] [Accepted: 10/03/2013] [Indexed: 11/25/2022]
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12
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Shell JR, Lawrence DS. Proteolytic regulation of the mitochondrial cAMP-dependent protein kinase. Biochemistry 2012; 51:2258-64. [PMID: 22385295 DOI: 10.1021/bi201573k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The mitochondrial cAMP-dependent protein kinase (PKA) is activatable in a cAMP-independent fashion. The regulatory (R) subunits of the PKA holoenzyme (R(2)C(2)), but not the catalytic (C) subunits, suffer proteolysis upon exposure of bovine heart mitochondria to digitonin, Ca(2+), and a myriad of electron transport inhibitors. Selective loss of both the RI- and RII-type subunits was demonstrated via Western blot analysis, and activation of the C subunit was revealed by phosphorylation of a validated PKA peptide substrate. Selective proteolysis transpires in a calpain-dependent fashion as demonstrated by exposure of the R and C subunits of PKA to calpain and by attenuation of R and C subunit proteolysis in the presence of calpain inhibitor I. By contrast, exposure of mitochondria to cAMP fails to promote R subunit degradation, although it does result in enhanced C subunit catalytic activity. Treatment of mitochondria with electron transport chain inhibitors rotenone, antimycin A, sodium azide, and oligomycin, as well as an uncoupler of oxidative phosphorylation, also elicits enhanced C subunit activity. These results are consistent with the notion that signals, originating from cAMP-independent sources, elicit enhanced mitochondrial PKA activity.
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Affiliation(s)
- Jennifer R Shell
- Departments of Chemistry, Chemical Biology and Medicinal Chemistry, and Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599, United States
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13
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Abstract
The calpains are a conserved family of cysteine proteinases that catalyse the controlled proteolysis of many specific substrates. Calpain activity is implicated in several fundamental physiological processes, including cytoskeletal remodelling, cellular signalling, apoptosis and cell survival. Calpain expression is altered during tumorigenesis, and the proteolysis of numerous substrates, such as inhibitors of nuclear factor-κB (IκB), focal adhesion proteins (including, focal adhesion kinase and talin) and proto-oncogenes (for example, MYC), has been implicated in tumour pathogenesis. Recent evidence indicates that the increased expression of certain family members might influence the response to cancer therapies, providing justification for the development of novel calpain inhibitors.
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Affiliation(s)
- Sarah J Storr
- University of Nottingham, School of Molecular Medical Sciences, Nottingham NG5 1PB, UK
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14
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Calpain digestion and HSP90-based chaperone protection modulate the level of plasma membrane F508del-CFTR. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1813:50-9. [PMID: 21111762 DOI: 10.1016/j.bbamcr.2010.11.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 11/12/2010] [Accepted: 11/17/2010] [Indexed: 11/23/2022]
Abstract
We are here showing that peripheral mononuclear blood cells (PBMC) from cystic fibrosis (CF) patients contain almost undetectable amounts of mature 170 kDa CF-transmembrane conductance regulator (CFTR) and a highly represented 100 kDa form. This CFTR protein, resembling the form produced by calpain digestion and present, although in lower amounts, also in normal PBMC, is localized in cytoplasmic internal vesicles. These observations are thus revealing that the calpain-mediated proteolysis is largely increased in cells from CF patients. To characterize the process leading to the accumulation of such split CFTR, FRT cells expressing the F508del-CFTR mutated channel protein and human leukaemic T cell line (JA3), expressing wild type CFTR were used. In in vitro experiments, the sensitivity of the mutated channel to the protease is identical to that of the wild type, whereas in Ca(2+)-loaded cells F508del-CFTR is more susceptible to digestion. Inhibition of intracellular calpain activity prevents CFTR degradation and leads to a 10-fold increase in the level of F508del-CFTR at the plasma membrane, further indicating the involvement of calpain activity in the maintenance of very low levels of mature channel form. The higher sensitivity to calpain of the mutated 170 kDa CFTR results from a reduced affinity for HSP90 causing a lower degree of protection from calpain digestion. The recovery of HSP90 binding capacity in F508del-CFTR, following digestion, explains the large accumulation of the 100 kDa CFTR form in circulating PBMC from CF patients.
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Kemp CM, Sensky PL, Bardsley RG, Buttery PJ, Parr T. Tenderness – An enzymatic view. Meat Sci 2010; 84:248-56. [DOI: 10.1016/j.meatsci.2009.06.008] [Citation(s) in RCA: 201] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2009] [Revised: 06/02/2009] [Accepted: 06/03/2009] [Indexed: 02/07/2023]
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16
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Stifanese R, Averna M, De Tullio R, Pedrazzi M, Beccaria F, Salamino F, Milanese M, Bonanno G, Pontremoli S, Melloni E. Adaptive modifications in the calpain/calpastatin system in brain cells after persistent alteration in Ca2+ homeostasis. J Biol Chem 2009; 285:631-43. [PMID: 19880516 DOI: 10.1074/jbc.m109.031674] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Persistent dysregulation in Ca(2+) homeostasis is a pervasive pathogenic mechanism in most neurodegenerative diseases, and accordingly, calpain activation has been implicated in neuronal cells dysfunction and death. In this study we examined the intracellular functional state of the calpain-calpastatin system in -G93A(+) SOD1 transgenic mice to establish if and how uncontrolled activation of calpain can be prevented in vivo during the course of prolonged [Ca(2+)](i) elevation. The presented data indicate that 1) calpain activation is more extensive in motor cortex, in lumbar, and sacral spinal cord segments compared with the lower or almost undetectable activation of the protease in other brain areas, 2) direct measurements of the variations of Ca(2+) levels established that the degree of the protease activation is correlated to the extent of elevation of [Ca(2+)](i), 3) intracellular activation of calpain is always associated with diffusion of calpastatin from perinuclear aggregated forms into the cytosol and the formation of a calpain-calpastatin complex, and 4) a conservative fragmentation of calpastatin is accompanied by its increased expression and inhibitory capacity in conditions of prolonged increase in [Ca(2+)](i). Thus, calpastatin diffusion and formation of the calpain-calpastatin complex together with an increased synthesis of the inhibitor protein represent a cellular defense response to conditions of prolonged dysregulation in intracellular Ca(2+) homeostasis. Altogether these findings provide a new understanding of the in vivo molecular mechanisms governing calpain activation that can be extended to many neurodegenerative diseases, potentially useful for the development of new therapeutic approaches.
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Affiliation(s)
- Roberto Stifanese
- Department of Experimental Medicine, Biochemistry Section, and Centre of Excellence for Biomedical Research, University of Genoa, Viale Benedetto XV, 1-16132 Genoa, Italy
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