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Claus W Heizmann - One of the best experts on this subject based on the ideXlab platform.
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Calcium-Binding Proteins of the EF-Hand Superfamily
Methods in Molecular Biology, 2020Co-Authors: Claus W HeizmannAbstract:This detailed volume explores protocols for studying the many facets of Ca2+-imaging, Ca2+-signaling, and Ca2+-binding along with background information on the principles and application of these techniques. The content of the book delves into 48 chapters including subjects such as data analysis and modern technologies to study Calcium-Binding and signaling in cells, the superfamily of Calcium-Binding Proteins characterized by the EF-hand structural motif, as well as their use as diagnostic and prognostic biomarkers in Laboratory Medicine and novel therapeutic drug targets. Written for the highly successful Methods in Molecular Biology series, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls. Authoritative and comprehensive, Calcium-Binding Proteins of the EF-Hand Superfamily: From Basics to Medical Applications presents state-of-the-art, lab-based methods and easy-to-follow protocols for daily use, making it interesting for basic and medical researchers, cell- and molecular biologists, clinicians, clinical chemists, and the diagnostic industry.
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The identification and differential expression of Calcium-Binding Proteins associated with ocular melanoma.
Biochimica et Biophysica Acta, 1998Co-Authors: Paul R. Van Ginkel, Teresa M. Walker, Claus W Heizmann, Dan-ning Hu, Arthur S PolansAbstract:Abstract Calcium-Binding Proteins may endow tumor cells with properties related to their malignancy and metastatic phenotype. Chromatographic procedures and amino acid sequence analysis were used in this study to identify seven Calcium-Binding Proteins, annexin VI, cap g, annexin V, calmodulin, S100A11, S100B and S100A6, associated with uveal melanoma, the primary ocular tumor of adults. This series of Calcium-Binding Proteins was identified in both primary tumors and cell lines of uveal melanoma. Several of the Proteins were shown by immunochemical methods to be differentially expressed between normal uveal melanocytes and malignant melanomas of the uvea. In addition, the expression of S100A6 may correlate with the malignant properties of the tumor.
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expression pattern of s100 calcium binding Proteins in human tumors
International Journal of Cancer, 1996Co-Authors: Beat W Schafer, Claus W HeizmannAbstract:The S100 Ca2+-binding Proteins recently became of major interest because of their differential expression in neoplastic tissues, their involvement in metastatic processes, and the clustered organization of at least 10 S100 genes on human chromosome 1q21, a region frequently rearranged in several tumors. As a first attempt towards a specific and differentiated immunohistochemical classification of human tumors, we produced, purified and characterized a number of human recombinant S100 Proteins and raised specific polyclonal antibodies. Their distinct cellular and intracellular localization was examined by immunohistochemical methods in normal and cancerogenic human tissues and cell lines. S100A1 and S100A2 can be detected in a few normal tissues only, whereas S100A4, S100A6, and S100B are expressed at higher levels in cancer tissues. In the future, these S100 antibodies will potentially be of great value in cancer diagnosis and therapy. © 1996 Wiley-Liss, Inc.
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the s100 family of ef hand calcium binding Proteins functions and pathology
Trends in Biochemical Sciences, 1996Co-Authors: Beat W Schafer, Claus W HeizmannAbstract:Calcium ions as second messengers control many biological processes, at least in part, via interaction with a large number of Ca 2+ -binding Proteins. One class of these Proteins shares a common Ca 2+ -binding motif, the EF-hand. Here, we describe some functional aspects of EF-hand Proteins, which have been found recently in different cellular compartments. Novel links between EF-hand Proteins, particularly S100 Proteins, and specific diseases are now emerging.
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isolation of a yac clone covering a cluster of nine s100 genes on human chromosome 1q21 rationale for a new nomenclature of the s100 calcium binding protein family
Genomics, 1995Co-Authors: Beat W Schafer, Roland Wicki, Dieter Engelkamp, Marie Geneviève Mattei, Claus W HeizmannAbstract:S100 Proteins are low-molecular-weight Calcium-Binding Proteins of the EF- hand superfamily and appear to be involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. More than 10 members of the S100 protein family have been described from human sources so far. We have now isolated a YAC clone from human chromosome 1q21, on which 9 different genes coding for S100 Calcium-Binding Proteins could be localized. Moreover, we have mapped the gene coding for S100P to human chromosome 4p16 and thereby completed the chromosomal assignments of all known human S100 genes. The clustered organization of S100 genes in the 1q21 region allows us to introduce a new logical nomenclature for these genes, which is based on the physical arrangement on the chromosomes. The new nomenclature should facilitate the further the understanding of this protein family and be easily expandable to other species. 31 refs., 4 figs., 1 tab.
Beat W Schafer - One of the best experts on this subject based on the ideXlab platform.
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expression pattern of s100 calcium binding Proteins in human tumors
International Journal of Cancer, 1996Co-Authors: Beat W Schafer, Claus W HeizmannAbstract:The S100 Ca2+-binding Proteins recently became of major interest because of their differential expression in neoplastic tissues, their involvement in metastatic processes, and the clustered organization of at least 10 S100 genes on human chromosome 1q21, a region frequently rearranged in several tumors. As a first attempt towards a specific and differentiated immunohistochemical classification of human tumors, we produced, purified and characterized a number of human recombinant S100 Proteins and raised specific polyclonal antibodies. Their distinct cellular and intracellular localization was examined by immunohistochemical methods in normal and cancerogenic human tissues and cell lines. S100A1 and S100A2 can be detected in a few normal tissues only, whereas S100A4, S100A6, and S100B are expressed at higher levels in cancer tissues. In the future, these S100 antibodies will potentially be of great value in cancer diagnosis and therapy. © 1996 Wiley-Liss, Inc.
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the s100 family of ef hand calcium binding Proteins functions and pathology
Trends in Biochemical Sciences, 1996Co-Authors: Beat W Schafer, Claus W HeizmannAbstract:Calcium ions as second messengers control many biological processes, at least in part, via interaction with a large number of Ca 2+ -binding Proteins. One class of these Proteins shares a common Ca 2+ -binding motif, the EF-hand. Here, we describe some functional aspects of EF-hand Proteins, which have been found recently in different cellular compartments. Novel links between EF-hand Proteins, particularly S100 Proteins, and specific diseases are now emerging.
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isolation of a yac clone covering a cluster of nine s100 genes on human chromosome 1q21 rationale for a new nomenclature of the s100 calcium binding protein family
Genomics, 1995Co-Authors: Beat W Schafer, Roland Wicki, Dieter Engelkamp, Marie Geneviève Mattei, Claus W HeizmannAbstract:S100 Proteins are low-molecular-weight Calcium-Binding Proteins of the EF- hand superfamily and appear to be involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. More than 10 members of the S100 protein family have been described from human sources so far. We have now isolated a YAC clone from human chromosome 1q21, on which 9 different genes coding for S100 Calcium-Binding Proteins could be localized. Moreover, we have mapped the gene coding for S100P to human chromosome 4p16 and thereby completed the chromosomal assignments of all known human S100 genes. The clustered organization of S100 genes in the 1q21 region allows us to introduce a new logical nomenclature for these genes, which is based on the physical arrangement on the chromosomes. The new nomenclature should facilitate the further the understanding of this protein family and be easily expandable to other species. 31 refs., 4 figs., 1 tab.
Walter J Chazin - One of the best experts on this subject based on the ideXlab platform.
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eLS - EF‐hand Calcium‐binding Proteins
Encyclopedia of Life Sciences, 2010Co-Authors: Melanie R. Nelson, Benjamin Chagot, Walter J ChazinAbstract:Calcium and the Proteins that bind to it play important roles in normal physiological processes and have been implicated in a variety of diseases. The importance of calcium is due mainly to its role as a second messenger in signal transduction. The calcium signal is mediated and controlled by many Proteins in the cell, the majority of which belong to the EF-hand super-family of Calcium-Binding Proteins. EF-hand Proteins are classified into calcium signal sensors and modulators. The calcium modulators fine-tune the shape and duration of calcium signals. The sensors undergo significant conformational changes when they bind calcium, which exposes new surfaces that interact with target Proteins. Together, EF-hand Calcium-Binding Proteins serve in the critical process of converting the ionic signal into activation of signalling pathways in cells. Key Concepts: The EF-hand is a helix–loop–helix structural motif. Calcium binds to oxygen atoms from the backbone and side-chain atoms of specific amino acids in EF-hand Calcium-Binding Proteins. The basic structural and functional unit of EF-hand Calcium-Binding Proteins is a pair of EF-hand motifs. EF-hand Calcium-Binding Proteins can be classified as sensors or modulators of calcium signals. EF-hand calcium senor Proteins need to transition from an ‘off ’ state at the resting level of calcium in the cell, to an ‘on’ (activated) state when calcium signals increase the concentration of calcium. The activation of EF-hand calcium sensor Proteins results from changes in structure induced by the binding of calcium ions. The binding of calcium activates EF-hand calcium sensor Proteins, triggering their interaction with target Proteins. Keywords: calcium; protein; signal transduction; calmodulin
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eLS - EF-Hand Calcium-Binding Proteins
Encyclopedia of Life Sciences, 2010Co-Authors: Melanie R. Nelson, Benjamin Chagot, Walter J ChazinAbstract:Calcium and the Proteins that bind to it play important roles in normal physiological processes and have been implicated in a variety of diseases. The importance of calcium is due mainly to its role as a second messenger in signal transduction. The calcium signal is mediated and controlled by many Proteins in the cell, the majority of which belong to the EF-hand super-family of Calcium-Binding Proteins. EF-hand Proteins are classified into calcium signal sensors and modulators. The calcium modulators fine-tune the shape and duration of calcium signals. The sensors undergo significant conformational changes when they bind calcium, which exposes new surfaces that interact with target Proteins. Together, EF-hand Calcium-Binding Proteins serve in the critical process of converting the ionic signal into activation of signalling pathways in cells. Key Concepts: The EF-hand is a helix–loop–helix structural motif. Calcium binds to oxygen atoms from the backbone and side-chain atoms of specific amino acids in EF-hand Calcium-Binding Proteins. The basic structural and functional unit of EF-hand Calcium-Binding Proteins is a pair of EF-hand motifs. EF-hand Calcium-Binding Proteins can be classified as sensors or modulators of calcium signals. EF-hand calcium senor Proteins need to transition from an ‘off ’ state at the resting level of calcium in the cell, to an ‘on’ (activated) state when calcium signals increase the concentration of calcium. The activation of EF-hand calcium sensor Proteins results from changes in structure induced by the binding of calcium ions. The binding of calcium activates EF-hand calcium sensor Proteins, triggering their interaction with target Proteins. Keywords: calcium; protein; signal transduction; calmodulin
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target selectivity in ef hand calcium binding Proteins
Biochimica et Biophysica Acta, 2004Co-Authors: Shibani Bhattacharya, Christopher G Bunick, Walter J ChazinAbstract:Abstract EF-hand calcium binding Proteins have remarkable sequence homology and structural similarity, yet their response to binding of calcium is diverse and they function in a wide range of biological processes. Knowledge of the fine-tuning of EF-hand protein sequences to optimize specific biochemical properties has been significantly advanced over the past 10 years by determination of atomic resolution structures. These data lay the foundation for addressing how functional selectivity is generated from a generic ionic signal. This review presents current ideas about the structural mechanisms that provide the selectivity of different EF-hand Proteins for specific cellular targets, using S100 and calmodulin family Proteins to demonstrate the critical concepts. Three factors contribute significantly to target selectivity: molecular architecture, response to binding of Ca 2+ ions, and the characteristics of target binding surfaces. Comparisons of calmodulin and S100 Proteins provide insights into the role these factors play in facilitating the variety of binding configurations necessary for recognizing a diverse set of targets.
Robert F Spencer - One of the best experts on this subject based on the ideXlab platform.
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Changes in Calcium-Binding protein expression in the auditory brainstem nuclei of the jaundiced Gunn rat
Hearing Research, 2002Co-Authors: Robert F Spencer, Ann T. Gleason, Wayne T Shaia, Aristides Sismanis, Steven M ShapiroAbstract:Sensorineural hearing loss and auditory dysfunction are major sequelae of neonatal hyperbilirubinemia. The sites and cellular effects of bilirubin toxicity in the auditory brainstem pathway are not easily detected. Since altered intracellular calcium homeostasis may play a role in neuronal cell death, we hypothesized that the expression of Calcium-Binding Proteins may be altered in the classic animal model of bilirubin neurotoxicity. The expression of the Calcium-Binding Proteins, calbindin-D28k and parvalbumin, in the brainstem auditory pathway of homozygous recessive jaundiced (jj) Gunn rats was examined by light and electron microscopic immunohistochemistry at 18 days postnatally and compared to the findings obtained from age-matched non-jaundiced heterozygous (Nj) littermate control rats. Immunoreactive staining for both calbindin and parvalbumin was reduced in the cochlear nuclei and the superior olivary complex in jj rats. The extent of the reduction in immunoreactivity was related to the severity of the clinical symptoms. By contrast, immunoreactive staining in other brainstem areas (e.g., dorsal and ventral nuclei of the lateral lemniscus, inferior colliculus), thalamic (medial geniculate body) auditory areas, and neighboring non-auditory structures was similar in jaundiced and control rats. Calbindin-immunoreactive staining in the superior paraolivary and medial superior olivary nuclei in Nj rats was associated with myelinated axons, whereas parvalbumin-immunoreactive staining was localized postsynaptically in neuronal somata and dendrites. Immunoreactive staining for the Calcium-Binding Proteins calbindin and parvalbumin in lower brainstem auditory nuclei shows abnormalities in areas susceptible to the effects of hyperbilirubinemia and provides a sensitive new way to assess bilirubin toxicity in the auditory system. © 2002 Elsevier Science B.V. All rights reserved.
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Immunohistochemical localization of Calcium-Binding Proteins in the brainstem vestibular nuclei of the jaundiced Gunn rat
Hearing Research, 2002Co-Authors: Wayne T Shaia, Andrew J. Heller, David L. Galiani, Steven M Shapiro, Aristides Sismanis, Robert F SpencerAbstract:Vestibular gaze and postural abnormalities are major sequelae of neonatal hyperbilirubinemia. The sites and cellular effects of bilirubin toxicity in the brainstem vestibular pathway are not easily detected. Since altered intracellular calcium homeostasis may play a role in neuronal cell death, we hypothesized that altered expression of Calcium-Binding Proteins may occur in brainstem vestibular nuclei of the classic animal model of bilirubin neurotoxicity. The expression of the Calcium-Binding Proteins calbindin-D28k and parvalbumin in the brainstem vestibular pathways and cerebellum of homozygous recessive jaundiced (jj) Gunn rats was examined by light microscopy and immunohistochemistry at 18 days postnatally and compared to the findings obtained from age-matched non-jaundiced heterozygous (Nj) littermate controls. Jaundiced animals exhibited decreased parvalbumin immunoreactivity specifically in synaptic inputs to superior, medial, and inferior vestibular nuclei, and to oculomotor and trochlear nuclei, whereas the neurons retained their normal immunoreactivity. Jaundiced animals also demonstrated a decrease in calbindin expression in the lateral vestibular nuclei and a paucity of calbindin-immunoreactive synaptic endings on the somata of Deiters' neurons. The involved regions are related to the control of the vestibulo-ocular and vestibulospinal reflexes. Decreased expression of Calcium-Binding Proteins in brainstem vestibular neurons may relate to the vestibulo-ocular and vestibulospinal dysfunction seen with clinical kernicterus, and may provide a sensitive new way to assess bilirubin toxicity in the vestibular system. © 2002 Elsevier Science B.V. All rights reserved.
Steven M Shapiro - One of the best experts on this subject based on the ideXlab platform.
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Changes in Calcium-Binding protein expression in the auditory brainstem nuclei of the jaundiced Gunn rat
Hearing Research, 2002Co-Authors: Robert F Spencer, Ann T. Gleason, Wayne T Shaia, Aristides Sismanis, Steven M ShapiroAbstract:Sensorineural hearing loss and auditory dysfunction are major sequelae of neonatal hyperbilirubinemia. The sites and cellular effects of bilirubin toxicity in the auditory brainstem pathway are not easily detected. Since altered intracellular calcium homeostasis may play a role in neuronal cell death, we hypothesized that the expression of Calcium-Binding Proteins may be altered in the classic animal model of bilirubin neurotoxicity. The expression of the Calcium-Binding Proteins, calbindin-D28k and parvalbumin, in the brainstem auditory pathway of homozygous recessive jaundiced (jj) Gunn rats was examined by light and electron microscopic immunohistochemistry at 18 days postnatally and compared to the findings obtained from age-matched non-jaundiced heterozygous (Nj) littermate control rats. Immunoreactive staining for both calbindin and parvalbumin was reduced in the cochlear nuclei and the superior olivary complex in jj rats. The extent of the reduction in immunoreactivity was related to the severity of the clinical symptoms. By contrast, immunoreactive staining in other brainstem areas (e.g., dorsal and ventral nuclei of the lateral lemniscus, inferior colliculus), thalamic (medial geniculate body) auditory areas, and neighboring non-auditory structures was similar in jaundiced and control rats. Calbindin-immunoreactive staining in the superior paraolivary and medial superior olivary nuclei in Nj rats was associated with myelinated axons, whereas parvalbumin-immunoreactive staining was localized postsynaptically in neuronal somata and dendrites. Immunoreactive staining for the Calcium-Binding Proteins calbindin and parvalbumin in lower brainstem auditory nuclei shows abnormalities in areas susceptible to the effects of hyperbilirubinemia and provides a sensitive new way to assess bilirubin toxicity in the auditory system. © 2002 Elsevier Science B.V. All rights reserved.
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Immunohistochemical localization of Calcium-Binding Proteins in the brainstem vestibular nuclei of the jaundiced Gunn rat
Hearing Research, 2002Co-Authors: Wayne T Shaia, Andrew J. Heller, David L. Galiani, Steven M Shapiro, Aristides Sismanis, Robert F SpencerAbstract:Vestibular gaze and postural abnormalities are major sequelae of neonatal hyperbilirubinemia. The sites and cellular effects of bilirubin toxicity in the brainstem vestibular pathway are not easily detected. Since altered intracellular calcium homeostasis may play a role in neuronal cell death, we hypothesized that altered expression of Calcium-Binding Proteins may occur in brainstem vestibular nuclei of the classic animal model of bilirubin neurotoxicity. The expression of the Calcium-Binding Proteins calbindin-D28k and parvalbumin in the brainstem vestibular pathways and cerebellum of homozygous recessive jaundiced (jj) Gunn rats was examined by light microscopy and immunohistochemistry at 18 days postnatally and compared to the findings obtained from age-matched non-jaundiced heterozygous (Nj) littermate controls. Jaundiced animals exhibited decreased parvalbumin immunoreactivity specifically in synaptic inputs to superior, medial, and inferior vestibular nuclei, and to oculomotor and trochlear nuclei, whereas the neurons retained their normal immunoreactivity. Jaundiced animals also demonstrated a decrease in calbindin expression in the lateral vestibular nuclei and a paucity of calbindin-immunoreactive synaptic endings on the somata of Deiters' neurons. The involved regions are related to the control of the vestibulo-ocular and vestibulospinal reflexes. Decreased expression of Calcium-Binding Proteins in brainstem vestibular neurons may relate to the vestibulo-ocular and vestibulospinal dysfunction seen with clinical kernicterus, and may provide a sensitive new way to assess bilirubin toxicity in the vestibular system. © 2002 Elsevier Science B.V. All rights reserved.
