1
|
Maize KM. Errors in Crystal structure of HINT from Helicobacter pylori. Acta Crystallogr F Struct Biol Commun 2016; 72:336-7. [PMID: 27050269 PMCID: PMC4822992 DOI: 10.1107/s2053230x16004088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 03/10/2016] [Indexed: 12/03/2022] Open
Abstract
Inaccuracies in the article, Crystal structure of HINT from Helicobacter pylori by Tarique et al. [(2016) Acta Cryst. F72, 42-48] are presented, and a brief history of HINT nomenclature is discussed.
Collapse
Affiliation(s)
- Kimberly M. Maize
- Medicinal Chemistry, University of Minnesota, 308 Harvard St SE, 8-101 Weaver-Densford Hall, Minneapolis, Minnesota 55455, USA
| |
Collapse
|
2
|
Liu Q, Puche AC, Wang JB. Distribution and Expression of Protein Kinase C Interactive Protein (PKCI/HINT1) in Mouse Central Nervous System (CNS). Neurochem Res 2008; 33:1263-76. [DOI: 10.1007/s11064-007-9578-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2007] [Accepted: 12/20/2007] [Indexed: 11/30/2022]
|
3
|
Guang W, Wang H, Su T, Weinstein IB, Wang JB. Role of mPKCI, a Novel μ-Opioid Receptor Interactive Protein, in Receptor Desensitization, Phosphorylation, and Morphine-Induced Analgesia. Mol Pharmacol 2004. [DOI: 10.1124/mol.66.5.1285] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
|
4
|
Su T, Suzui M, Wang L, Lin CS, Xing WQ, Weinstein IB. Deletion of histidine triad nucleotide-binding protein 1/PKC-interacting protein in mice enhances cell growth and carcinogenesis. Proc Natl Acad Sci U S A 2003; 100:7824-9. [PMID: 12810953 PMCID: PMC164672 DOI: 10.1073/pnas.1332160100] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
PKC-interacting protein (PKCI), also designated histidine triad nucleotide-binding protein 1, belongs to the histidine triad (HIT) family of proteins. Its structure is highly conserved from bacteria to humans and shares homology with the tumor-suppressor gene fragile histidine triad (FHIT). Although it was originally thought to inhibit PKC, its actual physiologic function is not known. Therefore, we used the technique of homologous recombination to generate homozygous deleted PKCI-/- mice. These mice display normal fetal and adult development. However, when mouse embryo fibroblasts were established from 13.5-day embryos and serially passaged the PKCI-/- cells displayed an increase in growth rate and underwent spontaneous immortalization, whereas the PKCI+/+ cells senesced and ceased growing. Furthermore, the PKCI-/- mouse embryo fibroblasts displayed increased resistance to cytotoxicity by ionizing radiation. In view of these findings we examined possible effects of PKCI on susceptibility to carcinogenicity. Both PKCI+/+ and PKCI-/- mice were treated with the chemical carcinogen N-nitrosomethylbenzylamine (NMBA) by intragastric administration and killed 12 weeks later. As expected with this protocol, NMBA induced squamous tumors (both papillomas and carcinomas) of the forestomach. The incidence, multiplicity per mouse, volume, and degree of malignancy of these tumors were significantly greater in the PKCI-/- than in the PKCI+/+ mice. Furthermore, four adenomas and one adenocarcinoma of the glandular stomach were found in the NMBA-treated PKCI-/- mice but no tumors of the glandular stomach were found in the NMBA-treated PKCI+/+ mice or in any of the untreated mice. Taken together, these findings suggest that, like FHIT, PKCI may normally play a tumor-suppressor role. The possible role of PKCI as a tumor suppressor in humans remains to be determined.
Collapse
Affiliation(s)
- Tao Su
- Herbert Irving Comprehensive Cancer Center and Integrated Program in Cellular, Molecular, and Biophysical Studies, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | | | | | | | | | | |
Collapse
|
5
|
Brenner C. Hint, Fhit, and GalT: function, structure, evolution, and mechanism of three branches of the histidine triad superfamily of nucleotide hydrolases and transferases. Biochemistry 2002; 41:9003-14. [PMID: 12119013 PMCID: PMC2571077 DOI: 10.1021/bi025942q] [Citation(s) in RCA: 226] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
HIT (histidine triad) proteins, named for a motif related to the sequence HphiHphiHphiphi (phi, a hydrophobic amino acid), are a superfamily of nucleotide hydrolases and transferases, which act on the alpha-phosphate of ribonucleotides, and contain a approximately 30 kDa domain that is typically either a homodimer of approximately 15 kDa polypeptides with two active-sites or an internally, imperfectly repeated polypeptide that retains a single HIT active site. On the basis of sequence, substrate specificity, structure, evolution, and mechanism, HIT proteins can be classified into the Hint branch, which consists of adenosine 5'-monophosphoramide hydrolases, the Fhit branch, which consists of diadenosine polyphosphate hydrolases, and the GalT branch, which consists of specific nucleoside monophosphate transferases, including galactose-1-phosphate uridylyltransferase, diadenosine tetraphosphate phosphorylase, and adenylyl sulfate:phosphate adenylytransferase. At least one human representative of each branch is lost in human diseases. Aprataxin, a Hint branch hydrolase, is mutated in ataxia-oculomotor apraxia syndrome. Fhit is lost early in the development of many epithelially derived tumors. GalT is deficient in galactosemia. Additionally, ASW is an avian Hint family member that has evolved to have unusual gene expression properties and the complete loss of its nucleotide binding site. The potential roles of ASW and Hint in avian sexual development are discussed elsewhere. Here we review what is known about biological activities of HIT proteins, the structural and biochemical bases for their functions, and propose a new enzyme mechanism for Hint and Fhit that may account for the differences between HIT hydrolases and transferases.
Collapse
Affiliation(s)
- Charles Brenner
- Structural Biology and Bioinformatics Program, Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.
| |
Collapse
|
6
|
Korsisaari N, Mäkelä TP. Interactions of Cdk7 and Kin28 with Hint/PKCI-1 and Hnt1 histidine triad proteins. J Biol Chem 2000; 275:34837-40. [PMID: 10958787 DOI: 10.1074/jbc.c000505200] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cyclin-dependent kinase 7 (Cdk7) forms a trimeric complex with cyclin H and Mat1 to form the mammalian Cdk-activating kinase, CAK, as well as a part of the basal transcription factor TFIIH, where Cdk7 phosphorylates the C-terminal domain (CTD) of the large subunit of RNA polymerase II. Here, we report a novel interaction between Cdk7 and a histidine triad (HIT) family protein, Hint/PKCI-1. This interaction was initially observed in a yeast two-hybrid study and subsequently verified by co-immunoprecipitation and subcellular localization studies, where overexpression of Cdk7 leads to partial relocalization of Hint to the nucleus. The physical association is independent of cyclin H binding or Cdk7 kinase activity and is conserved between the related Sacharomyces cerevisiae CTD kinase Kin28 and the HIT protein Hnt1. Furthermore, combination of a disruption of HNT1 and a KIN28 temperature-sensitive allele in S. cerevisiae led to highly elongated cell morphology and reduced colony formation, indicating a genetic interaction between KIN28 and HNT1. The physical and genetic interactions of Hint and Hnt1 with Cdk7 and Kin28 suggest a role for this class of histidine triad proteins in the regulation of Cdk7 and Kin28 functions.
Collapse
Affiliation(s)
- N Korsisaari
- Haartman Institute & Biocentrum Helsinki, P. O. Box 21, University of Helsinki, 00014 Helsinki, Finland
| | | |
Collapse
|
7
|
Abstract
Histidine triad (HIT) proteins were until recently a superfamily of proteins that shared only sequence motifs. Crystal structures of nucleotide-bound forms of histidine triad nucleotide-binding protein (Hint) demonstrated that the conserved residues in HIT proteins are responsible for their distinctive, dimeric, 10-stranded half-barrel structures that form two identical purine nucleotide-binding sites. Hint-related proteins, found in all forms of life, and fragile histidine triad (Fhit)-related proteins, found in animals and fungi, represent the two main branches of the HIT superfamily. Hint homologs are intracellular receptors for purine mononucleotides whose cellular function remains elusive. Fhit homologs bind and cleave diadenosine polyphosphates (Ap(n)A) such as ApppA and AppppA. Fhit-Ap(n)A complexes appear to function in a proapoptotic tumor suppression pathway in epithelial tissues. In invertebrates, Fhit homologs are encoded as fusion proteins with proteins related to plant and bacterial nitrilases that are candidate signaling partners in tumor suppression.
Collapse
Affiliation(s)
- C Brenner
- Kimmel Cancer Institute, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | | | | | | |
Collapse
|
8
|
Klein MG, Yao Y, Slosberg ED, Lima CD, Doki Y, Weinstein IB. Characterization of PKCI and comparative studies with FHIT, related members of the HIT protein family. Exp Cell Res 1998; 244:26-32. [PMID: 9770345 DOI: 10.1006/excr.1998.4153] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We previously described the isolation of a human cDNA that encodes a protein termed protein kinase C inhibitor (hPKCI). We elucidated the three-dimensional structure of this protein and demonstrated that in vitro, it enzymatically hydrolyzes adenosine polyphosphates. To identify other proteins that interact with hPKCI, in the present study, we used the hPKCI as a bait in the yeast two-hybrid system, together with a mouse embryo cDNA library. This led to the isolation of a murine PKCI homologue (mPKCI). This finding is consistent with our previous structural studies indicating that hPKCI exists as a homodimer and indicates the strong conservation of the PKCI sequence during evolution. Northern blot analysis indicated that a 0.7-kb PKCI mRNA was expressed in several tissues obtained from adult mice and also in a variety of rodent and human cell lines. Western blot analyses, using a polyclonal antibody prepared against hPKCI, indicated that this protein is expressed at relatively high levels in several murine tissues and in a variety of human cell lines prepared from normal tissues or tumors. In contrast to these findings, parallel studies with a polyclonal antibody to FHIT, a related histidine triad (HIT) protein and putative tumor suppressor, indicated that FHIT was expressed at low or undetectable levels in some of the same cell lines. Microscopy of immunostained cells indicated that the PKCI protein was present mainly in the nucleus of both normal and tumor-derived epithelial cell lines. Evidence presented in this and previous studies suggest that in vivo the ubiquitously expressed PKCI protein does not function as an inhibitor of PKC but rather acts as an enzyme in a yet to be identified pathway.
Collapse
Affiliation(s)
- M G Klein
- Herbert Irving Comprehensive Cancer Center, Room 1509, 701 West 168th Street, New York, New York, 10032, USA
| | | | | | | | | | | |
Collapse
|
9
|
Lima CD, D'Amico KL, Naday I, Rosenbaum G, Westbrook EM, Hendrickson WA. MAD analysis of FHIT, a putative human tumor suppressor from the HIT protein family. Structure 1997; 5:763-74. [PMID: 9261067 DOI: 10.1016/s0969-2126(97)00231-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The fragile histidine triad (FHIT) protein is a member of the large and ubiquitous histidine triad (HIT) family of proteins. It is expressed from a gene located at a fragile site on human chromosome 3, which is commonly disrupted in association with certain cancers. On the basis of the genetic evidence, it has been postulated that the FHIT protein may function as a tumor suppressor, implying a role for the FHIT protein in carcinogenesis. The FHIT protein has dinucleoside polyphosphate hydrolase activity in vitro, thus suggesting that its role in vivo may involve the hydrolysis of a phosphoanhydride bond. The structural analysis of FHIT will identify critical residues involved in substrate binding and catalysis, and will provide insights into the in vivo function of HIT proteins. RESULTS The three-dimensional crystal structures of free and nucleoside complexed FHIT have been determined from multiwavelength anomalous diffraction (MAD) data, and they represent some of the first successful structures to be measured with undulator radiation at the Advanced Photon Source. The structures of FHIT reveal that this protein exists as an intimate homodimer, which is based on a core structure observed previously in another human HIT homolog, protein kinase C interacting protein (PKCI), but has distinctive elaborations at both the N and C termini. Conserved residues within the HIT family, which are involved in the interactions of the proteins with nucleoside and phosphate groups, appear to be relevant for the catalytic activity of this protein. CONCLUSIONS The structure of FHIT, a divergent HIT protein family member, in complex with a nucleotide analog suggests a metal-independent catalytic mechanism for the HIT family of proteins. A structural comparison of FHIT with PKCI and galactose-1-phosphate uridylyltransferase (GaIT) reveals additional implications for the structural and functional evolution of the ubiquitous HIT family of proteins.
Collapse
Affiliation(s)
- C D Lima
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | | | | | | | | | | |
Collapse
|
10
|
Barnes LD, Garrison PN, Siprashvili Z, Guranowski A, Robinson AK, Ingram SW, Croce CM, Ohta M, Huebner K. Fhit, a putative tumor suppressor in humans, is a dinucleoside 5',5"'-P1,P3-triphosphate hydrolase. Biochemistry 1996; 35:11529-35. [PMID: 8794732 DOI: 10.1021/bi961415t] [Citation(s) in RCA: 275] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Human Fhit (fragile histidine triad) protein, encoded by the FHIT putative tumor suppressor gene, is a typical dinucleoside 5',5"'-P1,P3-triphosphate (Ap3A) hydrolase (EC 3.6.1.29) on the basis of its enzymatic properties we report here. Ap3A is the preferred substrate among ApnA (n = 3-6), and AMP is always one of the reaction products. Mn2+ and Mg2+ are equally stimulatory, while Zn2+ is inhibitory with Ap3A as the substrate. Values of the K(m) for Ap3A and Ap4A are 1.3 and 4.6 microM, respectively. Values of the specificity constant, kcat/K(m), for Ap3A and Ap4A are 2.0 x 10(6) and 6.7 x 10(3) s-1 M-1, respectively, for a glutathione S-transferase (GST)-Fhit fusion protein. Site-directed mutagenesis of FHIT demonstrated that all four conserved histidines are required for full activity, and the central histidine of the triad is absolutely essential for Ap3A hydrolase activity. This putative tumor suppressor is the first evidence for a connection between dinucleotide oligophosphate metabolism and tumorigenesis. Also, Fhit is the first HIT protein in which the histidine residues have been demonstrated by mutagenesis to be critical for function.
Collapse
Affiliation(s)
- L D Barnes
- Department of Biochemistry, University of Texas Health Science Center, San Antonio 78284-7760, USA.
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Lima CD, Klein MG, Weinstein IB, Hendrickson WA. Three-dimensional structure of human protein kinase C interacting protein 1, a member of the HIT family of proteins. Proc Natl Acad Sci U S A 1996; 93:5357-62. [PMID: 8643579 PMCID: PMC39250 DOI: 10.1073/pnas.93.11.5357] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The three-dimensional structure of protein kinase C interacting protein 1 (PKCI-1) has been solved to high resolution by x-ray crystallography using single isomorphous replacement with anomalous scattering. The gene encoding human PKCI-1 was cloned from a cDNA library by using a partial sequence obtained from interactions identified in the yeast two-hybrid system between PKCI-1 and the regulatory domain of protein kinase C-beta. The PKCI-1 protein was expressed in Pichia pastoris as a dimer of two 13.7-kDa polypeptides. PKCI-1 is a member of the HIT family of proteins, shown by sequence identity to be conserved in a broad range of organisms including mycoplasma, plants, and humans. Despite the ubiquity of this protein sequence in nature, no distinct function has been shown for the protein product in vitro or in vivo. The PKCI-1 protomer has an alpha+beta meander fold containing a five-stranded antiparallel sheet and two helices. Two protomers come together to form a 10-stranded antiparallel sheet with extensive contacts between a helix and carboxy terminal amino acids of a protomer with the corresponding amino acids in the other protomer. PKCI-1 has been shown to interact specifically with zinc. The three-dimensional structure has been solved in the presence and absence of zinc and in two crystal forms. The structure of human PKCI-1 provides a model of this family of proteins which suggests a stable fold conserved throughout nature.
Collapse
Affiliation(s)
- C D Lima
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | | | | | | |
Collapse
|
12
|
Affiliation(s)
- J P Liu
- Department of Medical Oncology, Newcastle Mater Misericordiae Hospital, New South Wales, Australia
| |
Collapse
|
13
|
Huang Y, Garrison PN, Barnes LD. Cloning of the Schizosaccharomyces pombe gene encoding diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) asymmetrical hydrolase: sequence similarity with the histidine triad (HIT) protein family. Biochem J 1995; 312 ( Pt 3):925-32. [PMID: 8554540 PMCID: PMC1136202 DOI: 10.1042/bj3120925] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Diadenosine 5',5"'-P1,P4-tetraphosphate (Ap4A) asymmetric hydrolase (EC 3.6.1.17) is a specific catabolic enzyme of Ap4A found in Schizosaccharomyces pombe. We have previously described the partial purification of Ap4A hydrolase from S. pombe [Robinson, de la Peña and Barnes (1993) Biochim. Biophys. Acta 1161, 139-148]. We determined the sequence of the N-terminal 20 amino acids of Ap4A hydrolase and designed two degenerate PCR primers based on the sequence. The 60 bp DNA fragment obtained by PCR, which is specific to Ap4A hydrolase, was used to isolate the Ap4A hydrolase gene, aph1, from S. pombe by screening a genomic DNA library in a multicopy plasmid. Ap4A hydrolase activity from the crude supernatant of a positive S. pombe transformant was about 25-fold higher than the control. There was no detectable stimulation of enzymic activity by phosphate. The aph1 gene from S. pombe contains three introns. The intron boundaries were confirmed by sequencing the cDNA of the aph1 gene from a S. pombe cDNA library. The deduced open reading frame of the aph1 gene codes for 182 amino acids. Two regions of significant local similarity were identified between the Ap4A hydrolase and the histidine triad (HIT) protein family [Séraphin (1992) DNA Sequence 3, 177-179]. HIT proteins are present in prokaryotes, yeast, plants and mammals. Their functions are unknown, except that the bovine protein inhibits protein kinase C in vitro. All four histidine residues which are conserved among the HIT proteins, including the HxHxH putative Zn(2+)-binding motif, are conserved in the Ap4A hydrolase. In addition, there are two regions of similarity between the Ap4A phosphorylases I and II from Saccharomyces cerevisiae and Ap4A hydrolase from S. pombe. These regions overlap with the HIT protein similarity regions. The aph1 gene from S. pombe is the first asymmetrical Ap4A hydrolase gene to be cloned and sequenced.
Collapse
Affiliation(s)
- Y Huang
- Department of Biochemistry, University of Texas Health Science Center at San Antonio 78284-7760, USA
| | | | | |
Collapse
|
14
|
Moore P, Hanson-Painton O, Morgenstern K, Grammas P. Regulation of protein kinase C activity in cerebral microvessels. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1995; 26:259-68. [PMID: 8748928 DOI: 10.1007/bf02815142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Regulation of protein kinase C (PKC)-mediated responses may occur by inhibition of PKC-dependent phosphorylation or by dephosphorylation of targets by specific phosphatases. Mechanisms for the regulation of PKC were examined in isolated cerebral microvessels and compared to those in brain. The data demonstrated that inhibitors of phosphorylation are responsible for the regulation in brain microvessels while dephosphorylation by protein phosphatases accounts for a substantial portion of the regulation of the PKC response in brain. In addition, the inhibitory activity apparently increases with age. These results suggest that the control of PKC may be cell-type specific and developmentally regulated.
Collapse
Affiliation(s)
- P Moore
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City 73104, USA
| | | | | | | |
Collapse
|
15
|
Eyster KM, McFarland DC. Production of an endogenous inhibitor of protein kinase C by embryonic myoblasts undergoing differentiation. Comp Biochem Physiol B Biochem Mol Biol 1995; 112:549-55. [PMID: 8529031 DOI: 10.1016/0305-0491(95)00107-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The current studies were undertaken to determine whether embryonic myoblasts or myogenic satellite cells undergoing differentiation and fusion contained endogenous modulators of protein kinase C (PKC). Clonal-derived turkey embryonic myoblast and satellite cell cultures were harvested at confluency and at approximately 40% fusion (embryonic myoblasts) or 75% fusion (satellite cells). PKC activity in cystosolic preparations of the cells and myotubes was undetectable. Cytosolic extracts (0.065 mg protein) of confluent and fused satellite cell cultures and confluent embryonic myoblasts had no effect on control PKC activity (control: 14.9 pmol/min, control + cytosols: 15.2, 13.9 and 13.5 pmol/min, respectively). Cytosolic preparations (0.065 mg protein) of embryonic myoblast-derived myotubes inhibited control PKC activity (4.0 pmol/min). In a time-course study, PKC-inhibitory activity was present in embryonic myoblasts at the earliest time point examined (30% fusion). Additionally, protein phosphatase activity correlated with PKC inhibitory activity. Thus, PKC-inhibitory activity appears as embryonic myoblasts begin to undergo fusion to form myotubes, but is not present in differentiating satellite cells.
Collapse
Affiliation(s)
- K M Eyster
- Department of Physiology and Pharmacology, University of South Dakota, Vermillion 57069, USA
| | | |
Collapse
|
16
|
Robinson K, Aitken A. Identification of a new protein family which includes bovine protein kinase C inhibitor-1. Biochem J 1994; 304 ( Pt 2):662-4. [PMID: 7999006 PMCID: PMC1137543 DOI: 10.1042/bj3040662] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
|
17
|
Allen BG, Andrea JE, Walsh MP. Identification and characterization of protein kinase C zeta-immunoreactive proteins. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(19)62043-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
|
18
|
Affiliation(s)
- P C Gordge
- Department of Clinical Oncology, University of Edinburgh, Western General Hospital, U.K
| | | |
Collapse
|
19
|
Eyster KM, Waller MS, Miller TL, Miller CJ, Olson DM. Protein phosphatase activity against protein kinase C-phosphorylated substrates in human placenta. Placenta 1994; 15:721-32. [PMID: 7838828 DOI: 10.1016/0143-4004(94)90035-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The presence of endogenous modulators of protein kinase C (PKC) in human placenta has not been reported. The specific activity of PKC in human placental cytosol was 20.52 +/- 1.8 pmol/min x mg protein. Partial purification of placental cytosol on diethylaminoethyl cellulose (DEAE) resulted in recovery of 145 per cent of original enzyme activity. Placental cytosol mixed with a control preparation of PKC significantly inhibited the control enzyme activity (control 42.42 +/- 2.8 pmol/min; control+placental cytosol 27.44 +/- 2.8 pmol/min, P < 0.05). The PKC-inhibitory activity was abolished by the addition of phosphatase inhibitors calyculin A (0.09 nM), microcystin LR (0.8 nM), and okadaic acid (0.4 nM). Protein substrates phosphorylated by PKC were rapidly dephosphorylated upon the addition of placental cytosol; this dephosphorylation was prevented by the presence of calyculin A and was removed by fractionation of placental cytosol on DEAE. Protein but not peptide substrate supported both the PKC-inhibitory activity and the dephosphorylation of PKC-phosphorylated substrates. The placental serine-threonine protein phosphatase was active against phosphorylase a, but not against substrate phosphorylated by cAMP-dependent protein kinase. These data indicate that the human placenta contains an endogenous inhibitor of PKC which interacts with substrate rather than with the PKC and that the inhibitor is a protein phosphatase.
Collapse
Affiliation(s)
- K M Eyster
- Department of Physiology and Pharmacology, University of South Dakota, School of Medicine, Vermillion 57069-2390
| | | | | | | | | |
Collapse
|
20
|
Simpson GG, Clark G, Brown JW. Isolation of a maize cDNA encoding a protein with extensive similarity to an inhibitor of protein kinase C and a cyanobacterial open reading frame. BIOCHIMICA ET BIOPHYSICA ACTA 1994; 1222:306-8. [PMID: 8031868 DOI: 10.1016/0167-4889(94)90183-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A full-length cDNA clone, Mz2-12, with a predicted amino acid sequence showing extensive similarity to the sequence of a protein inhibitor of protein kinase C, purified from bovine brain, has been isolated from maize. The sequence of Mz2-12 is also similar to an open reading frame of unknown function on a cyanobacterial dicistronic message. The extensive similarity of the three protein sequences identifies a novel class of evolutionarily conserved proteins.
Collapse
Affiliation(s)
- G G Simpson
- Department of Cell and Molecular Genetics, Scottish Crop Research Institute, Invergowrie, Dundee, UK
| | | | | |
Collapse
|
21
|
Hanson-Painton O, Morgenstern K, Cooper DR, Moore B, Botchlet T, Grammas P. Protein kinase C in rat cerebral microvessels. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1993; 20:245-61. [PMID: 8172627 DOI: 10.1007/bf03160077] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Activation of protein kinase C is a key event in the transduction of receptor-mediated extracellular signals. Little is known about the role of protein kinase C in the microcirculation of the brain. In this study, we examined protein kinase C in isolated cerebral microvessels. A technique for partial purification of protein kinase C from microvessels was employed, using Q-Sepharose batch adsorption and single-step salt elution in microfuge tubes. This procedure greatly reduced variability and increased protein kinase C specific activity in both the cytosolic and particulate fractions by nearly 50-fold. The identity of the enzyme was confirmed by its inhibition by staurosporine and bisindolylmaleimide and by its translocation in response to phorbol ester. The level of protein kinase C was assessed by [3H]phorbol ester binding and the endogenous substrates evaluated by in vitro phosphorylation studies. Finally, western blot analysis of protein kinase C isoforms indicated that the beta-isoform was present in both cytosolic and particulate fractions. The alpha-isoform was present at low levels in the cytosolic fraction, whereas the gamma-isoform was not detected.
Collapse
Affiliation(s)
- O Hanson-Painton
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City 73190
| | | | | | | | | | | |
Collapse
|
22
|
Blumenthal EJ, Copestake C, Hite G, Hoversland RC. Pregnancy-associated, lymphocyte-derived suppressor factor inhibits protein kinase C activity. J Reprod Immunol 1993; 24:97-109. [PMID: 8229996 DOI: 10.1016/0165-0378(93)90013-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
For successful allogenic pregnancy to occur, suppression of maternal defense responses toward the fetus are vital. Suppressor factors elaborated by decidual cells or immune cells may facilitate this suppression. In order for appropriate cellular responses to occur an intact signal transduction/second messenger system must be present. The calcium/phospholipid-dependent protein kinase, Pk-C, plays an important role in regulating immune responses, and may also be important in regulating uterine cell responses and implantation events. Pk-C activation is necessary for IL-2 synthesis and IL-2 receptor synthesis through activation of the proto-oncogenes c-jun and c-fos. These proto-oncogene gene products combine to form the heterodimer AP-1 which then activates IL-2 gene transcription for both peptide and receptor. If Pk-C activity becomes abrogated then appropriate cell responsiveness is diminished. We have shown that Pk-C activity is decreased in the particulate fraction of 4-7 day pregnant spleen, thymus and draining lymph node (DLN) cells. Spleen cells did not exhibit any change in cytosolic Pk-C activity, the thymus was found to have a decrease in both cytosol and particulate fractions, and the DLN cells exhibited a translocation effect whereby particulate Pk-C decreased and cytosolic Pk-C activity increased. Supernatant from 3-day cultures of DLN cells from pregnant animals was shown to inhibit proliferation of spleen cells. In addition, the supernatant was able to directly lower Pk-C activity. We hypothesize that DLN cells secrete a factor(s) that is able to suppress immune response through abrogation of Pk-C activity, thereby decreasing AP-1 formation resulting in decreased IL-2 synthesis and IL-2 receptor synthesis.
Collapse
Affiliation(s)
- E J Blumenthal
- Department of Biology, Indiana University-Purdue University at Fort Wayne 46805
| | | | | | | |
Collapse
|
23
|
Eyster KM. Protein kinase C activity in the rat ovary: increasing enzyme activity and presence of an endogenous inhibitor during pregnancy. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. COMPARATIVE PHYSIOLOGY 1993; 105:245-9. [PMID: 8101156 DOI: 10.1016/0300-9629(93)90203-g] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
1. Protein kinase C (PKC) activity was measured in corpora lutea and ovarian interstitial tissues obtained from rats on days 7, 13/14 and 20 of normal pregnancy. 2. PKC activity increased steadily from day 7 to day 20 of pregnancy in luteal tissue but not in ovarian interstitial tissues. 3. Cytosolic fractions of both tissue types inhibited PKC activity in a control preparation of the enzyme, suggesting that both tissues contain an endogenous inhibitor of PKC throughout pregnancy.
Collapse
Affiliation(s)
- K M Eyster
- Department of Physiology and Pharmacology, University of South Dakota, School of Medicine, Vermillion 57069-9986
| |
Collapse
|
24
|
DeManno DA, Maizels ET, Hunzicker-Dunn M. Hormonal regulation of the type III isoform of C-kinase in porcine ovarian tissues. Mol Cell Endocrinol 1992; 86:157-66. [PMID: 1511785 DOI: 10.1016/0303-7207(92)90140-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
C-kinase activity is notably increased in corpora lutea (CL) compared to preovulatory follicles of porcine ovaries. Our purpose was to identify the C-kinase isoform(s) involved in this increase and to examine the expression of C-kinase in ovarian tissues at different stages. The major component of C-kinase activity in the CL was isoform III, with a molecular weight (M(r)) of 80,000. Minor activities were attributed to the type II isoform (M(r) = 80,000) and an unidentified C-kinase activity (M(r) = 77,000). C-kinase was not partitioned differently in preovulatory follicles and CL as demonstrated by tissue homogenization in the presence of a detergent and increased chelators. A 3-fold increase in immunoreactive C-kinase was detected in postovulatory follicles relative to preovulatory. A second, nearly 3-fold increase in C-kinase was detected in mature CL relative to postovulatory follicles. These increases are examined in the context of the complex hormonal regulation of the porcine CL.
Collapse
Affiliation(s)
- D A DeManno
- Department of Cell, Molecular and Structural Biology, Northwestern University Medical School, Chicago 60611
| | | | | |
Collapse
|