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Zeitschriftenartikel zum Thema "Phosphoprotein phosphatases":
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Shacter, Emily, Joseph A. McClure, Edward D. Korn und P. Boon Chock. „Immunological characterization of phosphoprotein phosphatases“. Archives of Biochemistry and Biophysics 242, Nr. 2 (November 1985): 523–31. http://dx.doi.org/10.1016/0003-9861(85)90239-5.
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Vincent, John B., und Bruce A. Averill. „Sequence homology between purple acid phosphatases and phosphoprotein phosphatases“. FEBS Letters 263, Nr. 2 (24.04.1990): 265–68. http://dx.doi.org/10.1016/0014-5793(90)81389-6.
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Miller, W. Todd. „Tyrosine Phosphoprotein Phosphatases. Barry J. Goldstein“. Quarterly Review of Biology 74, Nr. 4 (Dezember 1999): 464–65. http://dx.doi.org/10.1086/394141.
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Zhang, Qingxiu, und Francois X. Claret. „Phosphatases: The New Brakes for Cancer Development?“ Enzyme Research 2012 (31.10.2012): 1–11. http://dx.doi.org/10.1155/2012/659649.
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The phosphatidylinositol 3-kinase (PI3K) pathway plays a pivotal role in the maintenance of processes such as cell growth, proliferation, survival, and metabolism in all cells and tissues. Dysregulation of the PI3K/Akt signaling pathway occurs in patients with many cancers and other disorders. This aberrant activation of PI3K/Akt pathway is primarily caused by loss of function of all negative controllers known as inositol polyphosphate phosphatases and phosphoprotein phosphatases. Recent studies provided evidence of distinct functions of the four main phosphatases—phosphatase and tensin homologue deleted on chromosome 10 (PTEN), Src homology 2-containing inositol 5′-phosphatase (SHIP), inositol polyphosphate 4-phosphatase type II (INPP4B), and protein phosphatase 2A (PP2A)—in different tissues with respect to regulation of cancer development. We will review the structures and functions of PTEN, SHIP, INPP4B, and PP2A phosphatases in suppressing cancer progression and their deregulation in cancer and highlight recent advances in our understanding of the PI3K/Akt signaling axis.
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Miskei, Márton, Csaba Ádám, László Kovács, Zsolt Karányi und Viktor Dombrádi. „Molecular Evolution of Phosphoprotein Phosphatases in Drosophila“. PLoS ONE 6, Nr. 7 (15.07.2011): e22218. http://dx.doi.org/10.1371/journal.pone.0022218.
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Moorhead, Greg B. G., Veerle De Wever, George Templeton und David Kerk. „Evolution of protein phosphatases in plants and animals“. Biochemical Journal 417, Nr. 2 (23.12.2008): 401–9. http://dx.doi.org/10.1042/bj20081986.
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Protein phosphorylation appears to be a universal mechanism of protein regulation. Genomics has provided the means to compile inventories of protein phosphatases across a wide selection of organisms and this has supplied insights into the evolution of this group of enzymes. Protein phosphatases evolved independently several times yielding the groups we observe today. Starting from a core catalytic domain, phosphatases evolved by a series of gene duplication events and by adopting the use of regulatory subunits and/or fusion with novel functional modules or domains. Recent analyses also suggest that the serine/threonine specific enzymes are more ancient than the PTPs (protein tyrosine phosphatases). It is likely that the latter played a key role at the onset of metazoan evolution in conjunction with the tremendous expansion of tyrosine kinases and PTPs at this point. In the present review, we discuss the evolution of the PTPs, the serine/threonine specific PPP (phosphoprotein phosphatase) and PPM (metallo-dependent protein phosphatase) families and the more recently discovered phosphatases that utilize an aspartate-based catalytic mechanism. We will also highlight examples of convergent evolution and several phosphatases which are unique to plants.
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Butler, Trent, Jonathan Paul, Nick Europe-Finner, Roger Smith und Eng-Cheng Chan. „Role of serine-threonine phosphoprotein phosphatases in smooth muscle contractility“. American Journal of Physiology-Cell Physiology 304, Nr. 6 (15.03.2013): C485—C504. http://dx.doi.org/10.1152/ajpcell.00161.2012.
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The degree of phosphorylation of myosin light chain 20 (MLC20) is a major determinant of force generation in smooth muscle. Myosin phosphatases (MPs) contain protein phosphatase (PP) 1 as catalytic subunits and are the major enzymes that dephosphorylate MLC20. MP regulatory targeting subunit 1 (MYPT1), the main regulatory subunit of MP in all smooth muscles, is a key convergence point of contractile and relaxatory pathways. Combinations of regulatory mechanisms, including isoform splicing, multiple phosphorylation sites, and scaffolding proteins, modulate MYPT1 activity with tissue and agonist specificities to affect contraction and relaxation. Other members of the PP1 family that do not target myosin, as well as PP2A and PP2B, dephosphorylate a range of proteins that affect smooth muscle contraction. This review discusses the role of phosphatases in smooth muscle contractility with a focus on MYPT1 in uterine smooth muscle. Myometrium shares characteristics of vascular and other visceral smooth muscles yet, during healthy pregnancy, undergoes hypertrophy, hyperplasia, quiescence, and labor as physiological processes. Myometrium presents an accessible model for the study of normal and pathological smooth muscle function, and a better understanding of myometrial physiology may allow the development of novel therapeutics for the many disorders of myometrial physiology from preterm labor to dysmenorrhea.
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Garvanska, Dimitriya H., und Jakob Nilsson. „Specificity determinants of phosphoprotein phosphatases controlling kinetochore functions“. Essays in Biochemistry 64, Nr. 2 (05.06.2020): 325–36. http://dx.doi.org/10.1042/ebc20190065.
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Abstract Kinetochores are instrumental for accurate chromosome segregation by binding to microtubules in order to move chromosomes and by delaying anaphase onset through the spindle assembly checkpoint (SAC). Dynamic phosphorylation of kinetochore components is key to control these activities and is tightly regulated by temporal and spatial recruitment of kinases and phosphoprotein phosphatases (PPPs). Here we focus on PP1, PP2A-B56 and PP2A-B55, three PPPs that are important regulators of mitosis. Despite the fact that these PPPs share a very similar active site, they target unique ser/thr phosphorylation sites to control kinetochore function. Specificity is in part achieved by PPPs binding to short linear motifs (SLiMs) that guide their substrate specificity. SLiMs bind to conserved pockets on PPPs and are degenerate in nature, giving rise to a range of binding affinities. These SLiMs control the assembly of numerous substrate specifying complexes and their position and binding strength allow PPPs to target specific phosphorylation sites. In addition, the activity of PPPs is regulated by mitotic kinases and inhibitors, either directly at the activity level or through affecting PPP–SLiM interactions. Here, we discuss recent progress in understanding the regulation of PPP specificity and activity and how this controls kinetochore biology.
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Wheeler-Jones, Caroline P. D., Rebecca A. Houliston und Jeremy D. Pearson. „Inhibitors of phosphoprotein phosphatases modulate p42mapk phosphorylation in endothelium“. Blood Coagulation & Fibrinolysis 6, Nr. 2 (April 1995): 173. http://dx.doi.org/10.1097/00001721-199504000-00068.
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Burns, Chris J., Shân L. Gyles, Shanta J. Persaud, David Sugden, Barbara J. Whitehouse und Peter M. Jones. „Phosphoprotein Phosphatases Regulate Steroidogenesis by Influencing StAR Gene Transcription“. Biochemical and Biophysical Research Communications 273, Nr. 1 (Juni 2000): 35–39. http://dx.doi.org/10.1006/bbrc.2000.2890.
Dissertationen zum Thema "Phosphoprotein phosphatases":
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Tan, Yves S. H. „Regulation of the type 1 protein phosphatase in saccharomyces cerevisiae“. free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3013031.
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Wadham, Carol. „Protein Tyrosine Phosphatase Pez : its role in the regulation of cell-cell adhesions“. Title page, abstract and table of contents only, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09phw122.pdf.
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"March 2003" Bibliography: leaves 206-233. The experimental data presented in this thesis provide evidence that PTP-Pez is an active phosphatase that interacts with and dephosphorylates the adherens junction protein ℓ-catenin. PTP-Pez also associates with proteins that form part of the tight junction complex, the scaffolding protein ZO-1 and the transmembrane protein occludin.
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Wallis, Lise J., und n/a. „Regulation of Bub1b phosphorylation by protein phosphatase 2A“. University of Otago. Dunedin School of Medicine, 2006. http://adt.otago.ac.nz./public/adt-NZDU20070502.114819.
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The mitotic spindle checkpoint plays a critical role during the cell cycle by protecting the faithful transmission of chromosomes during mitosis. If chromosomes are improperly bound to the spindle microtubules the checkpoint will prevent progress to anaphase by temporarily arresting cells in metaphase until all the chromosomes are correctly aligned. Bub1b is an essential component of the mitotic spindle checkpoint that transiently localises to kinetochores during mitosis and becomes phosphorylated, a response that is sustained during mitotic arrest. Bub1b has been implicated in other processes related to mitotic progression and is thought to regulate mitotic timing and have a role in caspase mediated cell death after prolonged mitotic arrest. The development of aneuploidy and cancer has been associated with mutations in the BUB1B gene and reduction in the level of Bub1b protein. To further our understanding of Bub1b function in the spindle checkpoint and mitosis, new protein interactions involving Bub1b were identified. This thesis describes the search for alternative proteins that interact with Bub1b, and their function in the mitotic spindle checkpoint and regulation of Bub1b activity.
Using a yeast two-hybrid approach, members of the B56 family of regulatory subunits of serine-threonine protein phosphatase (PP2A) were identified as novel interacting partners of Bub1b. Substrate specificity of PP2A is determined by the regulatory subunits. There are five characterised isoforms of the B56 family, each encoded by separate genes. In addition, some isoforms have several recognised splice variants. Confirmation of interactions by alternative methods demonstrated that the isoforms B56γ and B56[epsilon] preferentially interact with phosphorylated Bub1b, whereas the interaction of the remaining B56 isoforms (α, β and [delta]) occurs at a lower affinity with no specificity for the phosphorylated form. It was further demonstrated that B56γ1 associated with phosphorylated Bub1b in vivo.
Induced overexpression of splice variants of B56γ1 and B56γ2 demonstrated a significant reduction in levels of phosphorylated Bub1b during mitotic spindle checkpoint activation. In addition, an associated lower mitotic index was evident in cells with B56γ1 overexpression. Specific inhibition of PP2A activity with okadaic acid was shown to prolong Bub1b phosphorylation during normal mitosis and to restore the levels of phosphorylated Bub1b in arrested cells over expressing B56γ. These findings suggest a role for PP2A activity in regulation of Bub1b function that is mediated through substrate recognition by B56 regulatory subunits.
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Cheng, Lina. „Regulation of protein phosphatase 1, PP1 [gamma] 2, in testis/spermatozoa by PPP1R11, PPP1R7 and PPP1R2“. [Kent, Ohio] : Kent State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1208813693.
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Sheppard, Vonda Chantal. „Identification and characterization of diatom kinases catalyzing the phosphorylation of biomineral forming proteins“. Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/37227.
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Diatoms are unicellular photosynthetic algae that display intricately patterned cell walls made of amorphous silicon dioxide (silica). Long-chain polyamines and highly phosphorylated proteins, silaffins and silacidins, are believed to play an important role in biosilica formation. The phosphate moieties on silaffins and silacidins play a significant role in biomineral formation, yet no kinase has been identified that phosphorylates these biomineral forming proteins. This dissertation describes the characterization of a novel kinase from the diatom Thalassiosira pseudonana, tpSTK1, which is upregulated during silica formation. A recombinantly expressed histidine-tagged version of tpSTK1 was capable of phosphorylating recombinant silaffins but not recombinant silacidin in vitro. Through establishing methods for subcellular fraction of T. pseudonana membranes in combination with antibody inhibition assay, it was discovered that native tpSTK1 phosphorylates silaffins but not silacidins in vitro (i.e. it exhibits the same substrate specificity as recombinant tpSTK1). As tpSTK1 is an abundant protein in the ER lumen (~ 0.5 % of total ER protein) it seems highly likely to function as a silaffin kinase in vivo. TpSTK1 lacks clear sequence homologs in non-diatom organisms and is the first molecularly characterized kinase that appears to be involved in biomineralization.
The predicted kinase domain (KD) of tpSTK2, the only T. pseudonana homolog of tpSTK1, was recombinantly expressed and tested for phosphorylation activity. Recombinant tpSTK2-KD and native tpSTK2 exhibited detectable activity with myelin basic protein, but did not phosphorylate silaffins or silacidins in vitro. Western blot analysis demonstrated that native tpSTK2 was not present in the ER, but associated with the cytosol and Golgi membrane containing subcellular fractions.
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Lee, Gui-in. „Structure and dynamics of the receptor kinase interacting FHA domain of kinase associated protein kinase from arabidopsis“. Free to MU campus, others may purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3100058.
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Saraf, Amit Strack Stefan. „Regulation of tyrosine hydroxylase by protein phosphatase 2A“. [Iowa City, Iowa] : University of Iowa, 2008. http://ir.uiowa.edu/etd/429.
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Chakrabarti, Rumela. „Role for PP1 [gamma] 2 in spermatogenesis and sperm morphogenesis“. [Kent, Ohio] : Kent State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1176430377.
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Thesis (Ph.D.)--Kent State University, 2007. Title from PDF t.p. (viewed Mar. 12, 2009). Advisor: Srinivasan Vijayaraghavan. Keywords: sperm, testes, spermatogenesis, protein phosphatase, knock out, spermatid. Includes bibliographical references (p. 115-129).
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Sayed, Saba Bilquis. „Studies of the role of phosphoprotein phosphatases in the adrenal cortex“. Thesis, King's College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300432.
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Szapiel, Nicolas. „Glc7-E101Q is a novel tool for integrated genomic and proteomic analysis of PP1Glc7 phosphatase functional networks in Saccharomyces cerevisiae“. Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=101656.
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Reversible phosphorylation is a major mechanism for regulating the activity, localization and stability of proteins required for vital cellular processes such as glucose metabolism, gene expression, establishment of polarity, mitosis and cytokinesis. Phospho-regulation is driven by the activities of kinases and phosphatases. Together, these enzymes account for ∼3% of eukaryotic genomes and it is estimated that 30% of the eukaryotic proteome is composed of phospho-proteins. Protein kinases (PKs) have been studied extensively, however relatively little is known regarding the signaling networks of protein phosphatases (PPases). The identification of PPase functional networks has been slow due to the redundant nature of the majority of PPases, the complexity of their substrate recognition in vivo, and the lack of large-scale analyses that would facilitate network analysis. We hypothesized that large-scale analysis of genetic interactions using the Synthetic Genetic Array (SGA) and proteomic analyses using 2D-PAGE Difference Gel Electrophoresis (DiGE) could reveal PPase functional networks. Here, we apply this approach to the essential and conserved PP1 PPase Glc7 as it regulates numerous cellular processes in budding yeast. For this study, we created a glc7 hypomorphic mutant (glc7-E101Q) suited for both SGA and DiGE analyses. SGA analysis of glc7-E101Q revealed a broad network of 147 synthetic sick/lethal (SSL) and 178 synthetic rescue (SR) interactions. DiGE comparison of the glc7-E101Q proteome relative to wild-type at medium-resolution (∼1000 proteins) revealed alterations in 39 proteins that changed as a consequence of both the mutation and growth conditions. One of the proteins identified in this analysis was Eno1, a non-essential enolase that is mis-regulated in the presence of glucose and identified a SR mutation in the glc7-E101Q SGA. Subsequent phenotypic analysis suggests a novel, non-metabolic role for Eno1 in the Glc7 interaction network. Our results reveal that parallel analysis, using SGA and DIGE, can reveal novel functions and networks that a single analysis may not detect.
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Salvo, Joseph Di, und Wilfried Merlevede. Advances in protein phosphatases: Proceedings of the first international symposium, held at the Koninklijke Academie voor Geneeskunde van België August 20-23, 1985. Leuven, Belgium: Lueven University Press, 1985.
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International Conference on Second Messengers and Phosphoproteins (12th 2004 Montréal, Québec). Second messengers and phosphoprotein signaling: Proceedings of the 12th International Conference on Second Messengers and Phosphoproteins : Montreal, Canada, August 3-7, 2004. Herausgegeben von Anand-Srivastava Madhu B, Tremblay Michel und Srivastava Ashok K. Bologna: Medimond International Proceedings, 2004.
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Allison, William S., und Anne N. Murphy. Mitochondrial function: Mitochondrial protein kinases, protein phosphatases and mitochondrial diseases. San Diego, Calif: Academic Press/Elsevier, 2009.
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NATO Advanced Study Institute on Cellular Regulation by Protein Phosphorylation (1990 La Londe les Maures, France). Cellular regulation by protein phosphorylation. Berlin: Springer-Verlag, 1991.
Buchteile zum Thema "Phosphoprotein phosphatases":
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Ghahremani, Mina, und William C. Plaxton. „Phosphoprotein Phosphatase Function of Secreted Purple Acid Phosphatases“. In Protein Phosphatases and Stress Management in Plants, 11–28. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-48733-1_2.
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Abe, S., L. C. Huang und J. Larner. „Dephosphorylation of PDH by phosphoprotein phosphatases and its allosteric regulation by inositol glycans“. In Alpha-Keto Acid Dehydrogenase Complexes, 187–95. Basel: Birkhäuser Basel, 1996. http://dx.doi.org/10.1007/978-3-0348-8981-0_14.
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Schomburg, Dietmar, und Margit Salzmann. „Phosphoprotein phosphatase“. In Enzyme Handbook 3, 362–70. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76463-9_77.
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Schomburg, Dietmar, und Margit Salzmann. „Phosphoprotein phosphatase“. In Enzyme Handbook 3, 371–76. Berlin, Heidelberg: Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-76463-9_78.
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Mohandas, D. V., und S. Dales. „In Vivo and In Vitro Models of Demyelinating Disease: A Phosphoprotein Phosphatase in Host Cell Endosomes Dephosphorylating the Nucleocapsid Protein of Coronavirus JHM“. In Advances in Experimental Medicine and Biology, 255–60. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4684-5823-7_35.
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Ballou, Lisa M., und Edmond H. Fischer. „8 Phosphoprotein Phosphatases“. In Control by Phosphorylation Part A - General Features, Specific Enzymes (I), 311–61. Elsevier, 1986. http://dx.doi.org/10.1016/s1874-6047(08)60433-3.
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Hallaway, Brenda J., und Dennis J. O'Kane. „Chemiluminescence assay of serum alkaline phosphatase and phosphoprotein phosphatases“. In Bioluminescence and Chemiluminescence Part C, 391–401. Elsevier, 2000. http://dx.doi.org/10.1016/s0076-6879(00)05501-4.
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Brautigan, David L. „10 Phosphatases as partners in signaling networks“. In Advances in Second Messenger and Phosphoprotein Research, 113–24. Elsevier, 1997. http://dx.doi.org/10.1016/s1040-7952(97)80013-4.
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L., Jos, Elizabeth Baeza, Viviana M. und Juan C. „Connexins as Substrates for Protein Kinases and Phosphoprotein Phosphatases“. In Protein Kinases. InTech, 2012. http://dx.doi.org/10.5772/48019.
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Konferenzberichte zum Thema "Phosphoprotein phosphatases":
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Enouf, J., R. Bredoux, A. Giraud, N. Bourdeau und S. Levy-Toledano. „POSSIBLE RELATIONSHIP BETWEEN THE 23-kDa PHOSPHOPROTEIN AND THE IP3 -INDUCED Ca2+RELEASE IN HUMAN PLATELETS“. In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644516.
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The regulation of Ca2+ concentration in human platelets involves intracellular membranes i.e. dense tubular system (DTS). Agonist-induced platelet activation generates inositol 1,4,5 trisphosphate (IP3) which is responsible for Ca2+ mobilization from DTS. However, its mechanism of action is still unknown. cAMP has been shown to regulate Ca2+ transport by isolated membrane vesicles. This effect was correlated with the phosphorylation of a 23 kDa protein. We investigated whether this phosphorylation could play a role in the mechanism of IP3-induced Ca release.We isolated a membrane fraction enriched in intracellular membranes, which actively sequesters Ca2++. The Ca2+ uptake was mediated by a characterized (Ca2+ + Mg2+)-ATPase of a molecular weight 120 kDa. As well, the characterization of the 23-kDa protein phosphorylation by the catalytic subunit of the cAMP dependent protein kinase (C. Sub.) has been achieved. IP^-induced Ca release was tested on our membrane preparations. The transient effect was maximal at one minute and a dose-response curve was obtained.The cAMP dependent phosphorylation of the 23-kDa protein increased the Ca2+ liberation induced by IP by two fold whatever the IP3 concentration. The addition on the protein kinase inhibitor inhibited the IP3 -induced Ca2+ release.The effect of IP3 on the cAMP-mediated phosphorylation of the 23-kDa protein has been examinated.A dose dependent stimu-ulation of the 23-kDa protein phosphorylation in the presence of C. Sub. was initiated by IP3. The maximal effect was observed after 1-2 min and obtained with an IP3 concentration similar to that producing the maximal calcium release. The stimulation of the phosphorylation by IP3 was detected in the absence of Ca2+ and in the presence of phosphatase inhibitors.Therefore, we suggest a possible correlation between cAMP dependent phosphorylation of the 23-kDa protein and the IP3-induced Ca2+ release in human platelet membrane vesicles.
