101
|
Antoniades I, Stylianou P, Christodoulou N, Skourides PA. Addressing the Functional Determinants of FAK during Ciliogenesis in Multiciliated Cells. J Biol Chem 2016; 292:488-504. [PMID: 27895123 DOI: 10.1074/jbc.m116.767111] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Revised: 11/24/2016] [Indexed: 11/06/2022] Open
Abstract
We previously identified focal adhesion kinase (FAK) as an important regulator of ciliogenesis in multiciliated cells. FAK and other focal adhesion (FA) proteins associate with the basal bodies and their striated rootlets and form complexes named ciliary adhesions (CAs). CAs display similarities with FAs but are established in an integrin independent fashion and are responsible for anchoring basal bodies to the actin cytoskeleton during ciliogenesis as well as in mature multiciliated cells. FAK down-regulation leads to aberrant ciliogenesis due to impaired association between the basal bodies and the actin cytoskeleton, suggesting that FAK is an important regulator of the CA complex. However, the mechanism through which FAK functions in the complex is not clear, and in this study we examined the role of this protein in both ciliogenesis and ciliary function. We show that localization of FAK at CAs depends on interactions taking place at the amino-terminal (FERM) and carboxyl-terminal (FAT) domains and that both domains are required for proper ciliogenesis and ciliary function. Furthermore, we show that an interaction with another CA protein, paxillin, is essential for correct localization of FAK in multiciliated cells. This interaction is indispensable for both ciliogenesis and ciliary function. Finally, we provide evidence that despite the fact that FAK is in the active, open conformation at CAs, its kinase activity is dispensable for ciliogenesis and ciliary function revealing that FAK plays a scaffolding role in multiciliated cells. Overall these data show that the role of FAK at CAs displays similarities but also important differences compared with its role at FAs.
Collapse
Affiliation(s)
- Ioanna Antoniades
- From the Laboratory of Cell Biology and Molecular Embryology, Department of Biological Sciences, University of Cyprus, 1 University Avenue, Nicosia 2109, Cyprus
| | - Panayiota Stylianou
- From the Laboratory of Cell Biology and Molecular Embryology, Department of Biological Sciences, University of Cyprus, 1 University Avenue, Nicosia 2109, Cyprus
| | - Neophytos Christodoulou
- From the Laboratory of Cell Biology and Molecular Embryology, Department of Biological Sciences, University of Cyprus, 1 University Avenue, Nicosia 2109, Cyprus
| | - Paris A Skourides
- From the Laboratory of Cell Biology and Molecular Embryology, Department of Biological Sciences, University of Cyprus, 1 University Avenue, Nicosia 2109, Cyprus
| |
Collapse
|
102
|
ERK5 kinase activity is dispensable for cellular immune response and proliferation. Proc Natl Acad Sci U S A 2016; 113:11865-11870. [PMID: 27679845 DOI: 10.1073/pnas.1609019113] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Unlike other members of the MAPK family, ERK5 contains a large C-terminal domain with transcriptional activation capability in addition to an N-terminal canonical kinase domain. Genetic deletion of ERK5 is embryonic lethal, and tissue-restricted deletions have profound effects on erythroid development, cardiac function, and neurogenesis. In addition, depletion of ERK5 is antiinflammatory and antitumorigenic. Small molecule inhibition of ERK5 has been shown to have promising activity in cell and animal models of inflammation and oncology. Here we report the synthesis and biological characterization of potent, selective ERK5 inhibitors. In contrast to both genetic depletion/deletion of ERK5 and inhibition with previously reported compounds, inhibition of the kinase with the most selective of the new inhibitors had no antiinflammatory or antiproliferative activity. The source of efficacy in previously reported ERK5 inhibitors is shown to be off-target activity on bromodomains, conserved protein modules involved in recognition of acetyl-lysine residues during transcriptional processes. It is likely that phenotypes reported from genetic deletion or depletion of ERK5 arise from removal of a noncatalytic function of ERK5. The newly reported inhibitors should be useful in determining which of the many reported phenotypes are due to kinase activity and delineate which can be pharmacologically targeted.
Collapse
|
103
|
Ray D, Cuneo KC, Rehemtulla A, Lawrence TS, Nyati MK. Inducing Oncoprotein Degradation to Improve Targeted Cancer Therapy. Neoplasia 2016; 17:697-703. [PMID: 26476077 PMCID: PMC4611070 DOI: 10.1016/j.neo.2015.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/25/2015] [Accepted: 08/27/2015] [Indexed: 11/28/2022] Open
Abstract
Over the past decade, inhibition of the kinase activities of oncogenic proteins using small molecules and antibodies has been a mainstay of our anticancer drug development effort, resulting in several Food and Drug Administration–approved cancer therapies. The clinical effectiveness of kinase-targeted agents has been inconsistent, mostly because of the development of resistance. The expression and function of oncoproteins and tumor suppressors are regulated by numerous posttranslational protein modifications including phosphorylation, ubiquitination, and acetylation; hence, targeting specific posttranslational protein modifications provides for an attractive strategy for anticancer drug development. The present review discusses the hypothesis that targeted degradation of an oncoprotein may overcome many of the shortcomings seen with kinase inhibitors and that the approach would enable targeted inhibition of oncogenic proteins previously thought to be undruggable.
Collapse
Affiliation(s)
- Dipankar Ray
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48109
| | - Kyle C Cuneo
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48109
| | - Alnawaz Rehemtulla
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48109
| | - Theodore S Lawrence
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48109
| | - Mukesh K Nyati
- Department of Radiation Oncology, University of Michigan, Ann Arbor, MI, 48109.
| |
Collapse
|
104
|
Shang J, Lu S, Jiang Y, Zhang J. Allosteric modulators of MEK1: drug design and discovery. Chem Biol Drug Des 2016; 88:485-97. [PMID: 27115708 DOI: 10.1111/cbdd.12780] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Revised: 04/01/2016] [Accepted: 04/18/2016] [Indexed: 12/20/2022]
Abstract
Mitogen-activated protein kinase kinase (MAPKK, MEK) mediates signal transduction, controlling cell proliferation and survival. MEK occupies a key downstream position in the Ras-Raf-MEK-ERK signaling pathway, implying that inhibition of MEK will potently suppress tumor cell growth, with potential applications in cancer therapy. Based on the promising therapeutic effects of MEK modulators, continued efforts have been made in this class. Here, we review the discovery and development of MEK1 allosteric modulators, classifying them into four structural groups. The allosteric mechanisms and recent clinical progress involving these modulators are also reviewed.
Collapse
Affiliation(s)
- Jialin Shang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Shaoyong Lu
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Yongjun Jiang
- School of Biotechnology and Chemical Engineering, Ningbo Institute of Technology, Zhejiang University, Ningbo, China
| | - Jian Zhang
- Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Shanghai Jiao Tong University, School of Medicine, Shanghai, China. .,Medicinal Bioinformatics Center, Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
| |
Collapse
|
105
|
Li T, Liu H, Xue H, Zhang J, Han X, Yan S, Bo S, Liu S, Yuan L, Deng L, Li G, Wang Z. Neuroprotective Effects of Hydrogen Sulfide Against Early Brain Injury and Secondary Cognitive Deficits Following Subarachnoid Hemorrhage. Brain Pathol 2016; 27:51-63. [PMID: 26822402 DOI: 10.1111/bpa.12361] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2015] [Accepted: 01/24/2016] [Indexed: 01/17/2023] Open
Abstract
Although the neuroprotective effects of hydrogen sulfide (H2 S) have been demonstrated in several studies, whether H2 S protects against early brain injury (EBI) and secondary cognitive dysfunction in subarachnoid hemorrhage (SAH) model remains unknown. This study was undertaken to evaluate the influence of H2 S on both acute brain injury and neurobehavioral changes as well as the underlying mechanisms after SAH. The H2 S donor, NaHS, was administered via an intraperitoneal injection at a dose of 5.6 mg/kg at 2 h, 6 h, 24 h, and 46 h after SAH in rat model. The results showed that NaHS treatment significantly improved brain edema and neurobehavioral function, and attenuated neuronal cell death in the prefrontal cortex, associated with a decrease in Bax/Bcl-2 ratio and suppression of caspase-3 activation at 48 h after SAH. NaHS also promoted phospho-Akt and phospho-ERK levels. Furthermore, NaHS treatment significantly enhanced the levels of brain-derived neurotrophic factor (BDNF) and phospho-CREB. Importantly, NaHS administration improved learning and memory performance in the Morris water maze test at 7 days post-SAH in rats. These results demonstrated that NaHS, as an exogenous H2 S donor, could significantly alleviate the development of EBI and cognitive dysfunction induced by SAH via Akt/ERK-related antiapoptosis pathway, and upregulating BDNF-CREB expression.
Collapse
Affiliation(s)
- Tong Li
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China.,Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| | - Hansen Liu
- Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| | - Hao Xue
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Jinsen Zhang
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Xiao Han
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Shaofeng Yan
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Shishi Bo
- Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| | - Song Liu
- Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| | - Lin Yuan
- Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| | - Lin Deng
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Gang Li
- Department of Neurosurgery, Qilu Hospital of Shandong University and Brain Science Research Institute, Shandong University, 107#, Wenhua Xi Road, Jinan, Shandong Province, 250012, P.R. China
| | - Zhen Wang
- Department of Physiology, Shandong University School of Medicine, 44#, Wenhua Xi Road, Jinan, Shandong, 250012, P.R. China
| |
Collapse
|
106
|
Gierut JJ, Wood LB, Lau KS, Lin YJ, Genetti C, Samatar AA, Lauffenburger DA, Haigis KM. Network-level effects of kinase inhibitors modulate TNF-α-induced apoptosis in the intestinal epithelium. Sci Signal 2015; 8:ra129. [PMID: 26671150 DOI: 10.1126/scisignal.aac7235] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Individual signaling pathways operate in the context of the broader signaling network. Thus, the response of a cell to signals from the environment is affected by the state of the signaling network, such as the clinically relevant example of whether some components in the network are inhibited. The cytokine tumor necrosis factor-α (TNF-α) promotes opposing cellular behaviors under different conditions; the outcome is influenced by the state of the network. For example, in the mouse intestinal epithelium, inhibition of the mitogen-activated protein kinase (MAPK) kinase MEK alters the timing of TNF-α-induced apoptosis. We investigated whether MAPK signaling directly influences TNF-α-induced apoptosis or whether network-level effects secondary to inhibition of the MAPK pathway alter the cellular response. We found that inhibitors of the MAPK kinase kinase Raf, MEK, or extracellular signal-regulated kinase (ERK) exerted distinct effects on the timing and magnitude of TNF-α-induced apoptosis in the mouse intestine. Furthermore, even different MEK inhibitors exerted distinct effects; one, CH5126766, potentiated TNF-α-induced apoptosis, and the others reduced cell death. Computational modeling and experimental perturbation identified the kinase Akt as the primary signaling node that enhanced apoptosis in the context of TNF-α signaling in the presence of CH5126766. Our work emphasizes the importance of integrated network signaling in specifying cellular behavior in response to experimental or therapeutic manipulation. More broadly, this study highlighted the importance of considering the network-level effects of pathway inhibitors and showed the distinct effects of inhibitors that share the same target.
Collapse
Affiliation(s)
- Jessica J Gierut
- Cancer Research Institute, Beth Israel Deaconess Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Levi B Wood
- Cancer Research Institute, Beth Israel Deaconess Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ken S Lau
- Department of Chemical and Physical Biology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.,Epithelial Biology Center and Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Yi-Jang Lin
- Cancer Research Institute, Beth Israel Deaconess Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | - Casie Genetti
- Cancer Research Institute, Beth Israel Deaconess Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| | | | - Douglas A Lauffenburger
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Kevin M Haigis
- Cancer Research Institute, Beth Israel Deaconess Cancer Center and Department of Medicine, Harvard Medical School, Boston, MA 02215, USA
| |
Collapse
|
107
|
Mori N, Wildes F, Kakkad S, Jacob D, Solaiyappan M, Glunde K, Bhujwalla ZM. Choline kinase-α protein and phosphatidylcholine but not phosphocholine are required for breast cancer cell survival. NMR IN BIOMEDICINE 2015; 28:1697-1706. [PMID: 26503172 DOI: 10.1002/nbm.3429] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 09/03/2015] [Accepted: 09/11/2015] [Indexed: 06/05/2023]
Abstract
High levels of total choline and phosphocholine (PC) are consistently observed in aggressive cancers. Choline kinase (Chk) catalyzes choline phosphorylation to produce PC in phosphatidylcholine (PtdCho) biosynthesis. PtdCho is the most abundant phospholipid in eukaryotic cell membranes and plays a dual role as the structural component of membranes and as a substrate to produce lipid second messengers such as phosphatidic acid and diacylglycerol. Chk-α, but not Chk-β, is overexpressed in various cancers, and is closely associated with tumor progression and invasiveness. We have previously shown that downregulation of mRNA using small interfering RNA (siRNA) against Chk-α (siRNA-Chk) or Chk short hairpin RNA, and the resultant decrease of Chk-α protein levels, significantly reduced proliferation in breast cancer cells and tumors. A novel potent and selective small-molecule Chk-α inhibitor, V-11-0711, that inhibits the catalytic activity of Chk has recently been developed. Here, we used triple negative MDA-MB-231 and SUM149 breast cancer cells to further investigate the role of Chk-α in cancer, by examining Chk-α protein levels, cell viability/proliferation, choline phospholipid and lipid metabolism, lipid droplet formation, and apoptosis, following treatment with V-11-0711. Under the conditions used in this study, treatment with V-11-0711 significantly decreased PC levels but did not reduce cell viability as long as Chk-α protein and PtdCho levels were not reduced, suggesting that Chk-α protein and PtdCho, but not PC, may be crucial for breast cancer cell survival. These data also support the approach of antitumor strategies that destabilize Chk-α protein or downregulate PtdCho in breast cancer treatment.
Collapse
Affiliation(s)
- Noriko Mori
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Flonné Wildes
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Samata Kakkad
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Desmond Jacob
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Meiyappan Solaiyappan
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Kristine Glunde
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
- Sidney Kimmel Comprehensive Cancer Center, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| | - Zaver M Bhujwalla
- JHU ICMIC Program, Division of Cancer Imaging Research, The Russell H. Morgan Department of Radiology and Radiological Science, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
- Sidney Kimmel Comprehensive Cancer Center, School of Medicine, The Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
108
|
A positive feedback loop between Gli1 and tyrosine kinase Hck amplifies shh signaling activities in medulloblastoma. Oncogenesis 2015; 4:e176. [PMID: 26619401 PMCID: PMC4670963 DOI: 10.1038/oncsis.2015.38] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/26/2015] [Accepted: 10/27/2015] [Indexed: 12/17/2022] Open
Abstract
Sonic hedgehog (Shh) signaling is critical during normal development, and the abnormal activation of the Shh pathway is involved in many human cancers. As a target gene of the Shh pathway and as a transcription activator downstream of Shh signaling, Gli1 autoregulates and increases Shh signaling output. Gli1 is one of the key oncogenic factors in Shh-induced tumors such as medulloblastoma. Gli1 is posttranslationally modified, but the nature of the active form of Gli1 was unclear. Here we identified a Src family kinase Hck as a novel activator of Gli1. In Shh-responsive NIH3T3 cells, Hck interacts with Gli1 and phosphorylates multiple tyrosine residues in Gli1. Gli1-mediated target gene activation was significantly enhanced by Hck with both kinase activity-dependent and -independent mechanisms. We provide evidence showing that Hck disrupts the interaction between Gli1 and its inhibitor Sufu. In both NIH3T3 cells and cerebellum granule neuron precursors, the Hck gene is also a direct target of Gli1. Therefore, Gli1 and Hck form a positive feedback loop that amplifies Shh signaling transcription outcomes. In Shh-induced medulloblastoma, Hck is highly expressed and Gli1 is tyrosine phosphorylated, which may enhance the tumorigenic effects of the Gli1 oncogene. RNAi-mediated inhibition of Hck expression significantly repressed medulloblastoma cell growth. In summary, a novel positive feedback loop contributes to maximal Gli1 oncogenic activities in Shh-induced tumors such as medulloblastoma.
Collapse
|
109
|
Sipieter F, Cappe B, Gonzalez Pisfil M, Spriet C, Bodart JF, Cailliau-Maggio K, Vandenabeele P, Héliot L, Riquet FB. Novel Reporter for Faithful Monitoring of ERK2 Dynamics in Living Cells and Model Organisms. PLoS One 2015; 10:e0140924. [PMID: 26517832 PMCID: PMC4627772 DOI: 10.1371/journal.pone.0140924] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/01/2015] [Indexed: 12/18/2022] Open
Abstract
Uncoupling of ERK1/2 phosphorylation from subcellular localization is essential towards the understanding of molecular mechanisms that control ERK1/2-mediated cell-fate decision. ERK1/2 non-catalytic functions and discoveries of new specific anchors responsible of the subcellular compartmentalization of ERK1/2 signaling pathway have been proposed as regulation mechanisms for which dynamic monitoring of ERK1/2 localization is necessary. However, studying the spatiotemporal features of ERK2, for instance, in different cellular processes in living cells and tissues requires a tool that can faithfully report on its subcellular distribution. We developed a novel molecular tool, ERK2-LOC, based on the T2A-mediated coexpression of strictly equimolar levels of eGFP-ERK2 and MEK1, to faithfully visualize ERK2 localization patterns. MEK1 and eGFP-ERK2 were expressed reliably and functionally both in vitro and in single living cells. We then assessed the subcellular distribution and mobility of ERK2-LOC using fluorescence microscopy in non-stimulated conditions and after activation/inhibition of the MAPK/ERK1/2 signaling pathway. Finally, we used our coexpression system in Xenopus laevis embryos during the early stages of development. This is the first report on MEK1/ERK2 T2A-mediated coexpression in living embryos, and we show that there is a strong correlation between the spatiotemporal subcellular distribution of ERK2-LOC and the phosphorylation patterns of ERK1/2. Our approach can be used to study the spatiotemporal localization of ERK2 and its dynamics in a variety of processes in living cells and embryonic tissues.
Collapse
Affiliation(s)
- François Sipieter
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Molecular Signaling and Cell Death Unit, Inflammation Research Center (IRC), VIB, Ghent, Belgium
- Equipe Biophotonique Cellulaire Fonctionnelle, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS-UMR 8523, Villeneuve d'Ascq, France
- Regulation of Signal Division Team, Structural and Functional Glycobiology Unit (UGSF), CNRS-UMR 8576, Lille 1 University, Villeneuve d’Ascq, France
- Groupement de Recherche Microscopie Imagerie du Vivant, GDR2588 MIV-CNRS, Villeneuve d'Ascq, France
| | - Benjamin Cappe
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Molecular Signaling and Cell Death Unit, Inflammation Research Center (IRC), VIB, Ghent, Belgium
- Groupement de Recherche Microscopie Imagerie du Vivant, GDR2588 MIV-CNRS, Villeneuve d'Ascq, France
| | - Mariano Gonzalez Pisfil
- Equipe Biophotonique Cellulaire Fonctionnelle, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS-UMR 8523, Villeneuve d'Ascq, France
- Groupement de Recherche Microscopie Imagerie du Vivant, GDR2588 MIV-CNRS, Villeneuve d'Ascq, France
| | - Corentin Spriet
- TISBio, Structural and Functional Glycobiology Unit (UGSF), CNRS-UMR 8576, FR3688, Lille 1 University, Villeneuve d’Ascq, France
| | - Jean-François Bodart
- Regulation of Signal Division Team, Structural and Functional Glycobiology Unit (UGSF), CNRS-UMR 8576, Lille 1 University, Villeneuve d’Ascq, France
| | - Katia Cailliau-Maggio
- Regulation of Signal Division Team, Structural and Functional Glycobiology Unit (UGSF), CNRS-UMR 8576, Lille 1 University, Villeneuve d’Ascq, France
| | - Peter Vandenabeele
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Molecular Signaling and Cell Death Unit, Inflammation Research Center (IRC), VIB, Ghent, Belgium
- Methusalem Program, Ghent University, Ghent, Belgium
| | - Laurent Héliot
- Equipe Biophotonique Cellulaire Fonctionnelle, Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS-UMR 8523, Villeneuve d'Ascq, France
- Groupement de Recherche Microscopie Imagerie du Vivant, GDR2588 MIV-CNRS, Villeneuve d'Ascq, France
| | - Franck B. Riquet
- Molecular Signaling and Cell Death Unit, Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
- Molecular Signaling and Cell Death Unit, Inflammation Research Center (IRC), VIB, Ghent, Belgium
- Structural and Functional Glycobiology Unit (UGSF), CNRS-UMR 8576, Lille 1 University, Villeneuve d’Ascq, France
- Groupement de Recherche Microscopie Imagerie du Vivant, GDR2588 MIV-CNRS, Villeneuve d'Ascq, France
- * E-mail:
| |
Collapse
|
110
|
Cuneo KC, Nyati MK, Ray D, Lawrence TS. EGFR targeted therapies and radiation: Optimizing efficacy by appropriate drug scheduling and patient selection. Pharmacol Ther 2015; 154:67-77. [PMID: 26205191 PMCID: PMC4570853 DOI: 10.1016/j.pharmthera.2015.07.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 07/01/2015] [Indexed: 12/13/2022]
Abstract
The epidermal growth factor receptor (EGFR) plays an important role in tumor progression and treatment resistance for many types of malignancies including head and neck, colorectal, and nonsmall cell lung cancer. Several EGFR targeted therapies are efficacious as single agents or in combination with chemotherapy. Given the toxicity associated with chemoradiation and poor outcomes seen in several types of cancers, combinations of EGFR targeted agents with or without chemotherapy have been tested in patients receiving radiation. To date, the only FDA approved use of an anti-EGFR therapy in combination with radiation therapy is for locally advanced head and neck cancer. Given the important role EGFR plays in lung and colorectal cancer and the benefit of EGFR inhibition combined with chemotherapy in these disease sites, it is perplexing why EGFR targeted therapies in combination with radiation or chemoradiation have not been more successful. In this review we summarize the clinical findings of EGFR targeted therapies combined with radiation and chemoradiation regimens. We then discuss the interaction between EGFR and radiation including radiation induced EGFR signaling, the effect of EGFR on DNA damage repair, and potential mechanisms of radiosensitization. Finally, we examine the potential pitfalls with scheduling EGFR targeted therapies with chemoradiation and the use of predictive biomarkers to improve patient selection.
Collapse
Affiliation(s)
- Kyle C Cuneo
- University of Michigan, Department of Radiation Oncology, Ann Arbor, MI, United States; Ann Arbor Veterans Affairs Hospital, Department of Radiation Oncology, Ann Arbor, MI, United States
| | - Mukesh K Nyati
- University of Michigan, Department of Radiation Oncology, Ann Arbor, MI, United States
| | - Dipankar Ray
- University of Michigan, Department of Radiation Oncology, Ann Arbor, MI, United States
| | - Theodore S Lawrence
- University of Michigan, Department of Radiation Oncology, Ann Arbor, MI, United States.
| |
Collapse
|
111
|
Salvador-Reyes LA, Luesch H. Biological targets and mechanisms of action of natural products from marine cyanobacteria. Nat Prod Rep 2015; 32:478-503. [PMID: 25571978 DOI: 10.1039/c4np00104d] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Marine cyanobacteria are an ancient group of organisms and prolific producers of bioactive secondary metabolites. These compounds are presumably optimized by evolution over billions of years to exert high affinity for their intended biological target in the ecologically relevant organism but likely also possess activity in different biological contexts such as human cells. Screening of marine cyanobacterial extracts for bioactive natural products has largely focused on cancer cell viability; however, diversification of the screening platform led to the characterization of many new bioactive compounds. Targets of compounds have oftentimes been elusive if the compounds were discovered through phenotypic assays. Over the past few years, technology has advanced to determine mechanism of action (MOA) and targets through reverse chemical genetic and proteomic approaches, which has been applied to certain cyanobacterial compounds and will be discussed in this review. Some cyanobacterial molecules are the most-potent-in-class inhibitors and therefore may become valuable tools for chemical biology to probe protein function but also be templates for novel drugs, assuming in vitro potency translates into cellular and in vivo activity. Our review will focus on compounds for which the direct targets have been deciphered or which were found to target a novel pathway, and link them to disease states where target modulation may be beneficial.
Collapse
Affiliation(s)
- Lilibeth A Salvador-Reyes
- Department of Medicinal Chemistry, College of Pharmacy, University of Florida, Gainesville, Florida 32610, USA.
| | | |
Collapse
|
112
|
Lee HH, Wang YN, Hung MC. Non-canonical signaling mode of the epidermal growth factor receptor family. Am J Cancer Res 2015; 5:2944-58. [PMID: 26693051 PMCID: PMC4656722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 08/18/2015] [Indexed: 06/05/2023] Open
Abstract
Epidermal growth factor receptor (EGFR) and its family members are key players in both physiological and pathological settings for which they are well recognized as models for investigating the functions and regulations of other membrane receptor tyrosine kinases (RTKs) and serve as therapeutic targets critical to clinical need and fundamental research. The canonical view of the pivotal functions in the EGFR family has been well documented as being an initiator of signaling amplification cascades from the plasma membrane to different subcellular compartments via receptor endocytic trafficking, intermolecular interaction, and kinase-substrate reaction in a temporalspatial manner. However, several lines of evidence have identified non-canonical roles of the EGFR family, acting as a transcriptional factor and a chromatin regulator in the nucleus to regulate gene expression, DNA replication, and DNA damage repair. Moreover, the EGFR family can even exert its impact outside the host cell through exosomal vesicle secretion. The emerging concept of the non-canonical roles of the EGFR family reveals an astonishing and elaborate scheme on the molecular functions of membrane RTKs, offering new insights into the receptor biology as well as the development of comprehensive therapeutic strategies in the future.
Collapse
Affiliation(s)
- Heng-Huan Lee
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer CenterHouston 77030, TX, USA
| | - Ying-Nai Wang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer CenterHouston 77030, TX, USA
- Center for Molecular Medicine and Graduate Institute of Cancer Biology, China Medical UniversityTaichung 404, Taiwan
| | - Mien-Chie Hung
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer CenterHouston 77030, TX, USA
- Center for Molecular Medicine and Graduate Institute of Cancer Biology, China Medical UniversityTaichung 404, Taiwan
- The University of Texas Graduate School of Biomedical Sciences at HoustonHouston 77030, TX, USA
- Department of Biotechnology, Asia UniversityTaichung 413, Taiwan
| |
Collapse
|
113
|
Panneton V, Nath A, Sader F, Delaunay N, Pelletier A, Maier D, Oh K, Hipfner DR. Regulation of Catalytic and Non-catalytic Functions of the Drosophila Ste20 Kinase Slik by Activation Segment Phosphorylation. J Biol Chem 2015; 290:20960-20971. [PMID: 26170449 DOI: 10.1074/jbc.m115.645952] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Indexed: 01/21/2023] Open
Abstract
Protein kinases carry out important functions in cells both by phosphorylating substrates and by means of regulated non-catalytic activities. Such non-catalytic functions have been ascribed to many kinases, including some members of the Ste20 family. The Drosophila Ste20 kinase Slik phosphorylates and activates Moesin in developing epithelial tissues to promote epithelial tissue integrity. It also functions non-catalytically to promote epithelial cell proliferation and tissue growth. We carried out a structure-function analysis to determine how these two distinct activities of Slik are controlled. We find that the conserved C-terminal coiled-coil domain of Slik, which is necessary and sufficient for apical localization of the kinase in epithelial cells, is not required for Moesin phosphorylation but is critical for the growth-promoting function of Slik. Slik is auto- and trans-phosphorylated in vivo. Phosphorylation of at least two of three conserved sites in the activation segment is required for both efficient catalytic activity and non-catalytic signaling. Slik function is thus dependent upon proper localization of the kinase via the C-terminal coiled-coil domain and activation via activation segment phosphorylation, which enhances both phosphorylation of substrates like Moesin and engagement of effectors of its non-catalytic growth-promoting activity.
Collapse
Affiliation(s)
- Vincent Panneton
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada
| | - Apurba Nath
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada
| | - Fadi Sader
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Nathalie Delaunay
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Ariane Pelletier
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - Dominic Maier
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 2B2, Canada
| | - Karen Oh
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada
| | - David R Hipfner
- Institut de Recherches Cliniques de Montréal, Montreal, Quebec H2W 1R7, Canada; Molecular Biology Program, Université de Montréal, Montreal, Quebec H3T 3J7, Canada; Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 2B2, Canada; Department of Medicine, Université de Montréal, Montreal, Quebec H3C 3J7, Canada.
| |
Collapse
|
114
|
Fabbro D, Cowan-Jacob SW, Moebitz H. Ten things you should know about protein kinases: IUPHAR Review 14. Br J Pharmacol 2015; 172:2675-700. [PMID: 25630872 DOI: 10.1111/bph.13096] [Citation(s) in RCA: 233] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2014] [Revised: 12/31/2014] [Accepted: 01/20/2015] [Indexed: 12/12/2022] Open
Abstract
Many human malignancies are associated with aberrant regulation of protein or lipid kinases due to mutations, chromosomal rearrangements and/or gene amplification. Protein and lipid kinases represent an important target class for treating human disorders. This review focus on 'the 10 things you should know about protein kinases and their inhibitors', including a short introduction on the history of protein kinases and their inhibitors and ending with a perspective on kinase drug discovery. Although the '10 things' have been, to a certain extent, chosen arbitrarily, they cover in a comprehensive way the past and present efforts in kinase drug discovery and summarize the status quo of the current kinase inhibitors as well as knowledge about kinase structure and binding modes. Besides describing the potentials of protein kinase inhibitors as drugs, this review also focus on their limitations, particularly on how to circumvent emerging resistance against kinase inhibitors in oncological indications.
Collapse
Affiliation(s)
| | | | - Henrik Moebitz
- Novartis Institutes of Biomedical Research, Basel, Switzerland
| |
Collapse
|
115
|
The spinal muscular atrophy with pontocerebellar hypoplasia gene VRK1 regulates neuronal migration through an amyloid-β precursor protein-dependent mechanism. J Neurosci 2015; 35:936-42. [PMID: 25609612 DOI: 10.1523/jneurosci.1998-14.2015] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Spinal muscular atrophy with pontocerebellar hypoplasia (SMA-PCH) is an infantile SMA variant with additional manifestations, particularly severe microcephaly. We previously identified a nonsense mutation in Vaccinia-related kinase 1 (VRK1), R358X, as a cause of SMA-PCH. VRK1-R358X is a rare founder mutation in Ashkenazi Jews, and additional mutations in patients of different origins have recently been identified. VRK1 is a nuclear serine/threonine protein kinase known to play multiple roles in cellular proliferation, cell cycle regulation, and carcinogenesis. However, VRK1 was not known to have neuronal functions before its identification as a gene mutated in SMA-PCH. Here we show that VRK1-R358X homozygosity results in lack of VRK1 protein, and demonstrate a role for VRK1 in neuronal migration and neuronal stem cell proliferation. Using shRNA in utero electroporation in mice, we show that Vrk1 knockdown significantly impairs cortical neuronal migration, and affects the cell cycle of neuronal progenitors. Expression of wild-type human VRK1 rescues both proliferation and migration phenotypes. However, kinase-dead human VRK1 rescues only the migration impairment, suggesting the role of VRK1 in neuronal migration is partly noncatalytic. Furthermore, we found that VRK1 deficiency in human and mouse leads to downregulation of amyloid-β precursor protein (APP), a known neuronal migration gene. APP overexpression rescues the phenotype caused by Vrk1 knockdown, suggesting that VRK1 affects neuronal migration through an APP-dependent mechanism.
Collapse
|
116
|
Dong A, Wodziak D, Lowe AW. Epidermal growth factor receptor (EGFR) signaling requires a specific endoplasmic reticulum thioredoxin for the post-translational control of receptor presentation to the cell surface. J Biol Chem 2015; 290:8016-27. [PMID: 25666625 DOI: 10.1074/jbc.m114.623207] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The epidermal growth factor receptor (EGFR) is a well characterized receptor-tyrosine kinase that functions in development and serves a vital role in many human cancers. Understanding EGFR regulatory mechanisms, and hence approaches for clinical intervention, has focused on ligand-receptor interactions and tyrosine kinase activity. Here, we show using the NCI-H460 lung and A431 epidermoid human cancer cell lines that EGFR binding to anterior gradient homolog 2 (AGR2) in the endoplasmic reticulum is required for receptor delivery to the plasma membrane and thus EGFR signaling. Reduced AGR2 protein levels or mutation of an essential cysteine in the active site result in decreased cell surface EGFR and a concomitant decrease in signaling as reflected by AREG, EGR1, and FOS expression. Similar to previously described EGFR nulls, an AGR2 null also resulted in embryonic lethality. Consistent with its role in regulating EGFR-mediated signaling, AGR2 expression is also enhanced in many human cancers and promotes the transformed phenotype. Furthermore, EGFR-mediated signaling in NCI-H460 cells, which are resistant to the tyrosine kinase inhibitor AG1478, is also disrupted with reduced AGR2 expression. The results provide insights into why cancer prognosis or response to therapy often does not correlate with EGFR protein or RNA levels because they do not reflect delivery to the cell surface where signaling is initiated. AGR2, therefore, represents a novel post-translational regulator of EGFR-mediated signaling and a promising target for treating human cancers.
Collapse
Affiliation(s)
- Aiwen Dong
- From the Department of Medicine, Stanford University, Stanford, California 94305
| | - Dariusz Wodziak
- From the Department of Medicine, Stanford University, Stanford, California 94305
| | - Anson W Lowe
- From the Department of Medicine, Stanford University, Stanford, California 94305
| |
Collapse
|
117
|
Fang Z, Simard JR, Plenker D, Nguyen HD, Phan T, Wolle P, Baumeister S, Rauh D. Discovery of inter-domain stabilizers-a novel assay system for allosteric akt inhibitors. ACS Chem Biol 2015; 10:279-88. [PMID: 24959717 DOI: 10.1021/cb500355c] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In addition to the catalytically active kinase domain, most kinases feature regulatory domains that govern their activity. Modulating and interfering with these interdomain interactions presents a major opportunity for understanding biological systems and developing novel therapeutics. Therefore, small molecule inhibitors that target these interactions through an allosteric mode of action have high intrinsic selectivity, as these interactions are often unique to a single kinase or kinase family. Here we report the development of iFLiK (interface-Fluorescent Labels in Kinases), a fluorescence-based assay that can monitor such interdomain interactions. Using iFLiK, we have demonstrated selective detection of allosteric Akt inhibitors that induce an inactive closed conformation unique to Akt. This methodology easily distinguished small molecule allosteric inhibitors from classic ATP-competitive inhibitors. Screening an in-house compound library with iFLiK, we were able to identify novel compounds with a scaffold that has not been previously described for allosteric Akt inhibitors.
Collapse
Affiliation(s)
- Zhizhou Fang
- Technische Universität Dortmund, Fakultät
für Chemie und Chemische Biologie, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
- Chemical
Genomics
Centre of the Max Planck Society, Otto-Hahn-Strasse
15, 44227 Dortmund, Germany
| | - Jeffrey R. Simard
- Chemical
Genomics
Centre of the Max Planck Society, Otto-Hahn-Strasse
15, 44227 Dortmund, Germany
| | - Dennis Plenker
- University of Cologne, Medical Faculty, Department
of Translational Genomics, Weyertal 115b, 50931 Cologne, Germany
| | - Hoang D. Nguyen
- Chemical
Genomics
Centre of the Max Planck Society, Otto-Hahn-Strasse
15, 44227 Dortmund, Germany
| | - Trang Phan
- Chemical
Genomics
Centre of the Max Planck Society, Otto-Hahn-Strasse
15, 44227 Dortmund, Germany
| | - Patrik Wolle
- Technische Universität Dortmund, Fakultät
für Chemie und Chemische Biologie, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
| | - Stefan Baumeister
- Technische Universität Dortmund, Fakultät
für Chemie und Chemische Biologie, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
| | - Daniel Rauh
- Technische Universität Dortmund, Fakultät
für Chemie und Chemische Biologie, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany
- Chemical
Genomics
Centre of the Max Planck Society, Otto-Hahn-Strasse
15, 44227 Dortmund, Germany
| |
Collapse
|
118
|
Fabbro D. 25 Years of Small Molecular Weight Kinase Inhibitors: Potentials and Limitations. Mol Pharmacol 2014; 87:766-75. [DOI: 10.1124/mol.114.095489] [Citation(s) in RCA: 112] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
|
119
|
Novel approaches for targeting kinases: allosteric inhibition, allosteric activation and pseudokinases. Future Med Chem 2014; 6:541-61. [PMID: 24649957 DOI: 10.4155/fmc.13.216] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Protein kinases are involved in many essential cellular processes and their deregulation can lead to a variety of diseases, including cancer. The pharmaceutical industry has invested heavily in the identification of kinase inhibitors to modulate these disease-promoting pathways, resulting in several successful drugs. However, the field is challenging as it is difficult to identify novel selective inhibitors with good pharmacokinetic/pharmacodynamic properties. In addition, resistance to kinase inhibitor treatment frequently arises. The identification of non-ATP site targeting ('allosteric') inhibitors, the identification of kinase activators and the expansion of kinase target space to include the less studied members of the family, including atypical- and pseudo-kinases, are potential avenues to overcome these challenges. In this perspective, the opportunities and challenges of following these approaches and others will be discussed.
Collapse
|
120
|
Abstract
The phosphoinositide 3-kinase (PI3K) family is important to nearly all aspects of cell and tissue biology and central to human cancer, diabetes and aging. PI3Ks are spatially regulated and multifunctional, and together, act at nearly all membranes in the cell to regulate a wide range of signaling, membrane trafficking and metabolic processes. There is a broadening recognition of the importance of distinct roles for each of the three different PI3K classes (I, II and III), as well as for the different isoforms within each class. Ongoing issues include the need for a better understanding of the in vivo complexity of PI3K regulation and cellular functions. This Cell Science at a Glance article and the accompanying poster summarize the biochemical activities, cellular roles and functional requirements for the three classes of PI3Ks. In doing so, we aim to provide an overview of the parallels, the key differences and crucial interplays between the regulation and roles of the three PI3K classes.
Collapse
Affiliation(s)
- Steve Jean
- Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0380, USA
| | | |
Collapse
|
121
|
Thoma G, Drückes P, Zerwes HG. Selective inhibitors of the Janus kinase Jak3—Are they effective? Bioorg Med Chem Lett 2014; 24:4617-4621. [DOI: 10.1016/j.bmcl.2014.08.046] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2014] [Revised: 08/19/2014] [Accepted: 08/20/2014] [Indexed: 01/21/2023]
|
122
|
Leonard SE, Register AC, Krishnamurty R, Brighty GJ, Maly DJ. Divergent modulation of Src-family kinase regulatory interactions with ATP-competitive inhibitors. ACS Chem Biol 2014; 9:1894-905. [PMID: 24946274 PMCID: PMC4136698 DOI: 10.1021/cb500371g] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
![]()
Multidomain protein kinases, central
controllers of signal transduction,
use regulatory domains to modulate catalytic activity in a complex
cellular environment. Additionally, these domains regulate noncatalytic
functions, including cellular localization and protein–protein
interactions. Src-family kinases (SFKs) are promising therapeutic
targets for a number of diseases and are an excellent model for studying
the regulation of multidomain kinases. Here, we demonstrate that the
regulatory domains of the SFKs Src and Hck are divergently affected
by ligands that stabilize two distinct inactive ATP-binding site conformations.
Conformation-selective, ATP-competitive inhibitors differentially
modulate the ability of the SH3 and SH2 domains of Src and Hck to
engage in intermolecular interactions and the ability of the kinase–inhibitor
complex to undergo post-translational modification by effector enzymes.
This surprising divergence in regulatory domain behavior by two classes
of inhibitors that each stabilize inactive ATP-binding site conformations
is found to occur through perturbation or stabilization of the αC
helix. These studies provide insight into how conformation-selective,
ATP-competitive inhibitors can be designed to modulate domain interactions
and post-translational modifications distal to the ATP-binding site
of kinases.
Collapse
Affiliation(s)
- Stephen E. Leonard
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - A. C. Register
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Ratika Krishnamurty
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Gabriel J. Brighty
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Dustin J. Maly
- Department
of Chemistry, University of Washington, Seattle, Washington 98195, United States
| |
Collapse
|
123
|
Lozić I, Bartlett CA, Shaw JA, Iyer KS, Dunlop SA, Kilburn MR, Fitzgerald M. Changes in subtypes of Ca microdomains following partial injury to the central nervous system. Metallomics 2014; 6:455-64. [PMID: 24425149 DOI: 10.1039/c3mt00336a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rapid changes in Ca(2+) concentration and location in response to injury play key roles in a range of biological systems. However, quantitative analysis of changes in size and distribution of Ca(2+) microdomains in specific cell types in whole tissue samples has been limited by analytical resolution and reliance on indirect Ca(2+) indicator systems. Here, we combine the unique advantages of nanoscale secondary ion mass spectrometry (NanoSIMS) with immunohistochemistry to directly quantify changes in number, size and intensity of Ca microdomains specific to axonal or glial regions vulnerable to spreading damage following neurotrauma. Furthermore, using NanoSIMS allows separate quantification of Ca microdomains according to their co-localization with areas enriched in P. We rapidly excise and cryopreserve optic nerve segments from adult rat at time points ranging from 5 minutes to 3 months after injury, allowing assessment of Ca microdomains dynamics with minimal disruption due to tissue processing. We demonstrate significantly more non-P co-localized Ca microdomains in glial than axonal regions in normal optic nerve. The density of Ca microdomains not co-localized with areas enriched in P rapidly, selectively and significantly decreases after injury; densities of Ca microdomains co-localized with P enriched areas are unchanged. An efflux of Ca(2+) from microdomains not co-localized with P may contribute to the structural and functional deficits observed in nerve vulnerable to spreading damage following neurotrauma. NanoSIMS analyses of Ca microdomains allow quantitative and novel insights into Ca dynamics, applicable to a range of normal, as well as diseased or injured mammalian systems.
Collapse
Affiliation(s)
- Ivan Lozić
- BioNano, School of Chemistry and Biochemistry, The University of Western Australia, 35 Stirling Hwy, Crawley WA 6009, Australia
| | | | | | | | | | | | | |
Collapse
|
124
|
ErbB4 reduces synaptic GABAA currents independent of its receptor tyrosine kinase activity. Proc Natl Acad Sci U S A 2013; 110:19603-8. [PMID: 24218551 DOI: 10.1073/pnas.1312791110] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
ErbB4 signaling in the central nervous system is implicated in neuropsychiatric disorders and epilepsy. In cortical tissue, ErbB4 associates with excitatory synapses located on inhibitory interneurons. However, biochemical and histological data described herein demonstrate that the vast majority of ErbB4 is extrasynaptic and detergent-soluble. To explore the function of this receptor population, we used unbiased proteomics, in combination with electrophysiological, biochemical, and cell biological techniques, to identify a clinically relevant ErbB4-interacting protein, the GABAA receptor α1 subunit (GABAR α1). We show that ErbB4 and GABAR α1 are robustly coexpressed in hippocampal interneurons, and that ErbB4-null mice have diminished cortical GABAR α1 expression. Moreover, we characterize a Neuregulin-mediated ErbB4 signaling modality, independent of receptor tyrosine kinase activity, that couples ErbB4 to decreased postsynaptic GABAR currents on inhibitory interneurons. Consistent with an evolving understanding of GABAR trafficking, this pathway requires both clathrin-mediated endocytosis and protein kinase C to reduce GABAR inhibitory currents, surface GABAR α1 expression, and colocalization with the inhibitory postsynaptic protein gephyrin. Our results reveal a function of ErbB4, independent of its tyrosine kinase activity, that modulates postsynaptic inhibitory control of hippocampal interneurons and may provide a novel pharmacological target in the treatment of neuropsychiatric disorders and epilepsy.
Collapse
|
125
|
Thomas MP, Potter BVL. The enzymes of human diphosphoinositol polyphosphate metabolism. FEBS J 2013; 281:14-33. [PMID: 24152294 PMCID: PMC4063336 DOI: 10.1111/febs.12575] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 09/10/2013] [Accepted: 10/15/2013] [Indexed: 12/22/2022]
Abstract
Diphospho-myo-inositol polyphosphates have many roles to play, including roles in apoptosis, vesicle trafficking, the response of cells to stress, the regulation of telomere length and DNA damage repair, and inhibition of the cyclin-dependent kinase Pho85 system that monitors phosphate levels. This review focuses on the three classes of enzymes involved in the metabolism of these compounds: inositol hexakisphosphate kinases, inositol hexakisphosphate and diphosphoinositol-pentakisphosphate kinases and diphosphoinositol polyphosphate phosphohydrolases. However, these enzymes have roles beyond being mere catalysts, and their interactions with other proteins have cellular consequences. Through their interactions, the three inositol hexakisphosphate kinases have roles in exocytosis, diabetes, the response to infection, and apoptosis. The two inositol hexakisphosphate and diphosphoinositol-pentakisphosphate kinases influence the cellular response to phosphatidylinositol (3,4,5)-trisphosphate and the migration of pleckstrin homology domain-containing proteins to the plasma membrane. The five diphosphoinositol polyphosphate phosphohydrolases interact with ribosomal proteins and transcription factors, as well as proteins involved in membrane trafficking, exocytosis, ubiquitination and the proteasomal degradation of target proteins. Possible directions for future research aiming to determine the roles of these enzymes are highlighted.
Collapse
Affiliation(s)
- Mark P Thomas
- Department of Pharmacy & Pharmacology, University of Bath, UK
| | | |
Collapse
|
126
|
Baljuls A, Kholodenko BN, Kolch W. It takes two to tango--signalling by dimeric Raf kinases. MOLECULAR BIOSYSTEMS 2013; 9:551-8. [PMID: 23212737 DOI: 10.1039/c2mb25393c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Raf kinases function downstream of Ras proteins to activate the MEK-ERK pathway which is deregulated in a large number of human cancers. Raf inhibitors are clinically highly effective for the treatment of cancer and melanoma in particular, but have unexpected side effects that include a paradoxical activation of the ERK pathway. These effects seem to be related to the heterodimerization of Raf-1 and B-Raf kinases. Here, we discuss the role of Raf dimerization as part of the physiological activation mechanism of Raf kinases, the mechanism of Raf dimerization induced by drugs, and the implications of dimerization for drug therapies targeting Raf kinases.
Collapse
Affiliation(s)
- Angela Baljuls
- Systems Biology Ireland, University College Dublin, Dublin 4, Ireland.
| | | | | |
Collapse
|
127
|
Case AJ, Mezhir JJ, O'Leary BR, Hrabe JE, Domann FE. Rational design of a secreted enzymatically inactive mutant of extracellular superoxide dismutase. Redox Rep 2013; 17:239-45. [PMID: 23339859 DOI: 10.1179/1351000212y.0000000028] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Extracellular superoxide dismutase (SOD3) is a secreted enzyme that regulates levels of extracellular superoxide and protects the extracellular matrix from degradation by reactive species. The SOD3 protein contains a heparin-binding domain and resides in a microenvironment rich in other heparin-bound growth factors, raising the possibility that SOD3 may have some biological role independent of its catalytic activity. To begin to address this, we designed and created enzymatically inactive mutant constructs targeting either the copper coordinating (i.e. H96 and H98) or superoxide channeling (i.e. N180 and R186) amino acid residues of SOD3. All constructs expressed equal quantities of immature intracellular SOD proteins, but only the N180A, R186A, and combination N180A/R186A mutants produced fully processed and secreted extracellular protein. Furthermore, while SOD activity was significantly inhibited in the single N180A and R186A mutants, the activity was completely abrogated in the N180A/R186A double mutant. Overall, the use of this novel tool may have broad reaching impacts into various fields of biology and medicine, and will aid in the delineation of cellular processes that are regulated by solely the SOD3 protein, its reactive oxygen species substrates and products, or the combination of both.
Collapse
Affiliation(s)
- Adam J Case
- Free Radical and Radiation Biology Program, Department of Radiation Oncology, Holden Comprehensive Cancer Center, The University of Iowa, Iowa City, IA 52242, USA
| | | | | | | | | |
Collapse
|
128
|
LKB1 controls human bronchial epithelial morphogenesis through p114RhoGEF-dependent RhoA activation. Mol Cell Biol 2013; 33:2671-82. [PMID: 23648482 DOI: 10.1128/mcb.00154-13] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
LKB1 is a Ser/Thr kinase that plays an important role in controlling both energy metabolism and cell polarity in metazoan organisms. LKB1 is also a tumor suppressor, and homozygous, inactivating mutations are found in a wide range of human cancers. In lung cancer, inactivating mutations are found in 10 to 50% of cases, but the consequences of functional loss in this context are poorly understood. We report here that LKB1 is required for the maturation of apical junctions in the human bronchial epithelial cell line 16HBE14o- (16HBE). This activity is dependent on an interaction with the Rho guanine nucleotide exchange factor p114RhoGEF but is independent of LKB1 kinase activity. Together, LKB1 and p114RhoGEF control RhoA activity in these cells to promote apical junction assembly.
Collapse
|
129
|
Wierk JK, Langbehn A, Kamper M, Richter S, Burda PC, Heussler VT, Deschermeier C. Plasmodium berghei MAPK1 displays differential and dynamic subcellular localizations during liver stage development. PLoS One 2013; 8:e59755. [PMID: 23544094 PMCID: PMC3609774 DOI: 10.1371/journal.pone.0059755] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 02/18/2013] [Indexed: 11/18/2022] Open
Abstract
Mitogen-activated protein kinases (MAPKs) regulate key signaling events in eukaryotic cells. In the genomes of protozoan Plasmodium parasites, the causative agents of malaria, two genes encoding kinases with significant homology to other eukaryotic MAPKs have been identified (mapk1, mapk2). In this work, we show that both genes are transcribed during Plasmodium berghei liver stage development, and analyze expression and subcellular localization of the PbMAPK1 protein in liver stage parasites. Live cell imaging of transgenic parasites expressing GFP-tagged PbMAPK1 revealed a nuclear localization of PbMAPK1 in the early schizont stage mediated by nuclear localization signals in the C-terminal domain. In contrast, a distinct localization of PbMAPK1 in comma/ring-shaped structures in proximity to the parasite's nuclei and the invaginating parasite membrane was observed during the cytomere stage of parasite development as well as in immature blood stage schizonts. The PbMAPK1 localization was found to be independent of integrity of a motif putatively involved in ATP binding, integrity of the putative activation motif and the presence of a predicted coiled-coil domain in the C-terminal domain. Although PbMAPK1 knock out parasites showed normal liver stage development, the kinase may still fulfill a dual function in both schizogony and merogony of liver stage parasites regulated by its dynamic and stage-dependent subcellular localization.
Collapse
Affiliation(s)
- Jannika Katharina Wierk
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Annette Langbehn
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Maria Kamper
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | - Stefanie Richter
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| | | | | | - Christina Deschermeier
- Department of Molecular Parasitology, Bernhard Nocht Institute for Tropical Medicine, Hamburg, Germany
| |
Collapse
|
130
|
Fang Z, Grütter C, Rauh D. Strategies for the selective regulation of kinases with allosteric modulators: exploiting exclusive structural features. ACS Chem Biol 2013; 8:58-70. [PMID: 23249378 DOI: 10.1021/cb300663j] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The modulation of kinase function has become an important goal in modern drug discovery and chemical biology research. In cancer-targeted therapies, kinase inhibitors have been experiencing an upsurge, which can be measured by the increasing number of kinase inhibitors approved by the FDA in recent years. However, lack of efficacy, limited selectivity, and the emergence of acquired drug resistance still represent major bottlenecks in the clinic and challenge inhibitor development. Most known kinase inhibitors target the active kinase and are ATP competitive. A second class of small organic molecules, which address remote sites of the kinase and stabilize enzymatically inactive conformations, is rapidly moving to the forefront of kinase inhibitor research. Such allosteric modulators bind to sites that are less conserved across the kinome and only accessible upon conformational changes. These molecules are therefore thought to provide various advantages such as higher selectivity and extended drug target residence times. This review highlights various strategies that have been developed to utilizing exclusive structural features of kinases and thereby modulating their activity allosterically.
Collapse
Affiliation(s)
- Zhizhou Fang
- Technische Universität Dortmund, Fakultät
Chemie − Chemische Biologie, Otto-Hahn-Strasse
6, D-44227 Dortmund, Germany
| | - Christian Grütter
- Technische Universität Dortmund, Fakultät
Chemie − Chemische Biologie, Otto-Hahn-Strasse
6, D-44227 Dortmund, Germany
| | - Daniel Rauh
- Technische Universität Dortmund, Fakultät
Chemie − Chemische Biologie, Otto-Hahn-Strasse
6, D-44227 Dortmund, Germany
| |
Collapse
|
131
|
Falcon SC, Hudson CS, Huang Y, Mortimore M, Golec JM, Charlton PA, Weber P, Sundaram H. A non-catalytic role of choline kinase alpha is important in promoting cancer cell survival. Oncogenesis 2013; 2:e38. [PMID: 25522435 PMCID: PMC3641355 DOI: 10.1038/oncsis.2013.2] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Revised: 01/11/2013] [Accepted: 01/17/2013] [Indexed: 01/09/2023] Open
Abstract
Choline kinase alpha (ChoKα) is regarded as an attractive cancer target. The enzyme catalyses the formation of phosphocholine(PCho), an important precursor in the generation of phospholipids essential for cell growth. ChoKα has oncogenic properties and is critical for the survival of cancer cells. Overexpression of the ChoKα protein can transform noncancer cells into cells with a cancerous phenotype, and depletion of the ChoKα protein can result in cancer cell death. However, the mechanisms underlying the tumourigenic properties of ChoKα are not fully understood. ChoKα was recently demonstrated to associate with other oncogenic proteins, raising the possibility that a non-catalytic protein scaffolding function drives the tumourigenic properties of ChoKα rather than a catalytic function. In order to differentiate these two roles, we compared the impact on cancer cell survival using two tools specific for ChoKα: (1) small interfering RNA (siRNA) to knockdown the ChoKα protein levels; and (2) compound V-11-0711, a novel potent and selective ChoKα inhibitor (ChoKα IC50 20 nM), to impede the catalytic activity. Both treatments targeted the endogenous ChoKα protein in HeLa cells, as demonstrated by a substantial reduction in the PCho levels. siRNA knockdown of the ChoKα protein in HeLa cells resulted in significant cell death through apoptosis. In contrast, compound V-11-0711 caused a reversible growth arrest. This suggests that inhibition of ChoKα catalytic activity alone is not sufficient to kill cancer cells, and leads us to conclude that there is a role for the ChoKα protein in promoting cancer cell survival that is independent of its catalytic activity.
Collapse
Affiliation(s)
- S C Falcon
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - C S Hudson
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - Y Huang
- Vertex Pharmaceuticals Inc, Cambridge, MA, USA
| | - M Mortimore
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - J M Golec
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - P A Charlton
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - P Weber
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| | - H Sundaram
- Vertex Pharmaceuticals (Europe) Limited, Abingdon, Oxfordshire, UK
| |
Collapse
|
132
|
Krishnamurty R, Brigham JL, Leonard SE, Ranjitkar P, Larson ET, Dale EJ, Merritt EA, Maly DJ. Active site profiling reveals coupling between domains in SRC-family kinases. Nat Chem Biol 2012; 9:43-50. [PMID: 23143416 PMCID: PMC3522794 DOI: 10.1038/nchembio.1118] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 10/01/2012] [Indexed: 12/14/2022]
Abstract
Protein kinases, key regulators of intracellular signal transduction, have emerged as an important class of drug targets. Chemical proteomic tools that facilitate the functional interrogation of protein kinase active sites are powerful reagents for studying the regulation of this large enzyme family and for performing inhibitor selectivity screens. Here we describe a new crosslinking strategy that enables rapid and quantitative profiling of protein kinase active sites in lysates and live cells. Applying this methodology to the SRC-family kinases (SFKs) SRC and HCK led to the identification of a series of conformation-specific, ATP-competitive inhibitors that display a distinct preference for autoinhibited forms of these kinases. Furthermore, we show that ligands that demonstrate this selectivity are able to modulate the ability of the regulatory domains of SRC and HCK to engage in intermolecular binding interactions. These studies provide insight into the regulation of this important family of tyrosine kinases.
Collapse
|
133
|
Noiseux N, Borie M, Desnoyers A, Menaouar A, Stevens LM, Mansour S, Danalache BA, Roy DC, Jankowski M, Gutkowska J. Preconditioning of stem cells by oxytocin to improve their therapeutic potential. Endocrinology 2012; 153:5361-72. [PMID: 23024264 DOI: 10.1210/en.2012-1402] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Principal limitation of cell therapy is cell loss after transplantation because of the interplay between ischemia, inflammation, and apoptosis. We investigated the mechanism of preconditioning of mesenchymal stem cells (MSCs) with oxytocin (OT), which has been proposed as a novel strategy for enhancing therapeutic potential of these cells in ischemic heart. In this study, we demonstrate that rat MSCs express binding sites for OT receptor and OT receptor transcript and protein as detected by RT-PCR and immunofluorescence, respectively. In response to OT (10(-10) to 10(-6) M) treatment, MSCs respond with rapid calcium mobilization and up-regulation of the protective protein kinase B (PKB or Akt) and phospho-ERK1/2 proteins. In OT-stimulated cells, phospho-Akt accumulates intracellularly close to the mitochondrial marker cytochrome c oxidase subunit 4. Functional analyses reveal the involvement of Akt/ERK1/2 pathways in cell proliferation, migration, and protection against the cytotoxic and apoptotic effects of hypoxia and serum deprivation. In addition, OT preconditioning increases MSC glucose uptake. Genes with angiogenic, antiapoptotic, and cardiac antiremodeling properties, such as heat shock proteins (hsps) HSP27, HSP32, HSP70, vascular endothelial growth factor, thrombospondin, tissue inhibitor of metalloproteinase (TIMP)-1, TIMP-2, TIMP-3, and matrix metalloproteinase-2, were also up-regulated upon OT exposure. Moreover, coculture with OT-preconditioned MSC reduces apoptosis, as measured using terminal transferase dUTP nick end labeling assay in newborn rat cardiomyocytes exposed to hypoxia and reoxygenation. In conclusion, these results indicate that OT treatment evokes MSC protection through both intrinsic pathways and secretion of cytoprotective factors. Ex vivo cellular treatment with OT represents an attractive strategy aimed to maximize the biological and functional properties of effector cells.
Collapse
Affiliation(s)
- Nicolas Noiseux
- Centre de Recherche, Department of Medicine, Université de Montréal, Québec, Canada.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
134
|
Knight JDR, Pawson T, Gingras AC. Profiling the kinome: current capabilities and future challenges. J Proteomics 2012; 81:43-55. [PMID: 23099349 DOI: 10.1016/j.jprot.2012.10.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 10/09/2012] [Accepted: 10/14/2012] [Indexed: 01/08/2023]
Abstract
Protein kinases are the second largest human protein family, but in terms of research interest, both basic and applied, they are surely the most popular. Over the past decade, many techniques and approaches for studying the kinome have been described and the pace of development is ever increasing. Presently, a molecular biologist can approach the kinome from many different angles: what kinases are active during a specific cell state of interest or become activated in response to a specific stimulus? What are the effects of controlling the activation status of an individual kinase? What substrates are targeted by a particular kinase, either in general or under particular conditions? And what kinase is responsible for targeting a specific phosphorylation site of interest? These are some of the more commonly asked questions during any kinase-centric research project and different strategies have been devised for answering such queries. In this review, we outline the most promising of these approaches, particularly those with a capacity for high-throughput studies. This article is part of a Special Issue entitled: From protein structures to clinical applications.
Collapse
Affiliation(s)
- James D R Knight
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada M5G 1X5
| | | | | |
Collapse
|
135
|
Goyal A, Poluzzi C, Willis CD, Smythies J, Shellard A, Neill T, Iozzo RV. Endorepellin affects angiogenesis by antagonizing diverse vascular endothelial growth factor receptor 2 (VEGFR2)-evoked signaling pathways: transcriptional repression of hypoxia-inducible factor 1α and VEGFA and concurrent inhibition of nuclear factor of activated T cell 1 (NFAT1) activation. J Biol Chem 2012; 287:43543-56. [PMID: 23060442 DOI: 10.1074/jbc.m112.401786] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Endorepellin, the angiostatic C-terminal domain of the heparan sulfate proteoglycan perlecan, inhibits angiogenesis by simultaneously binding to the α2β1 integrin and the vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) on endothelial cells. This interaction triggers the down-regulation of both receptors and the concurrent activation of the tyrosine phosphatase SHP-1, which leads to a signaling cascade resulting in angiostasis. Here, we provide evidence that endorepellin is capable of attenuating both the PI3K/PDK1/Akt/mTOR and the PKC/JNK/AP1 pathways. We show that hypoxia-inducible factor 1α (HIF-1α) transcriptional activity induced by VEGFA was inhibited by endorepellin independent of oxygen concentration and that only a combination of both PI3K and calcineurin inhibitors completely blocked the suppressive activity evoked by endorepellin on HIF1A and VEGFA promoter activity. Moreover, endorepellin inhibited the PKC/JNK/AP1 axis induced by the recruitment of phospholipase γ and attenuated the VEGFA-induced activation of NFAT1, a process dependent on calcineurin activity. Finally, endorepellin inhibited VEGFA-evoked nuclear translocation of NFAT1 and promoted NFAT1 stability. Thus, we provide evidence for a novel downstream signaling axis for an angiostatic fragment and for the key components involved in the dual antagonistic activity of endorepellin, highlighting its potential use as a therapeutic agent.
Collapse
Affiliation(s)
- Atul Goyal
- Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
| | | | | | | | | | | | | |
Collapse
|
136
|
Abstract
Dual-specificity MAP kinase phosphatases (MKPs) provide a complex negative regulatory network that acts to shape the duration, magnitude and spatiotemporal profile of MAP kinase activities in response to both physiological and pathological stimuli. Individual MKPs may exhibit either exquisite specificity towards a single mitogen-activated protein kinase (MAPK) isoform or be able to regulate multiple MAPK pathways in a single cell or tissue. They can act as negative feedback regulators of MAPK activity, but can also provide mechanisms of crosstalk between distinct MAPK pathways and between MAPK signalling and other intracellular signalling modules. In this review, we explore the current state of knowledge with respect to the regulation of MKP expression levels and activities, the mechanisms by which individual MKPs recognize and interact with different MAPK isoforms and their role in the spatiotemporal regulation of MAPK signalling.
Collapse
|
137
|
Getlik M, Simard JR, Termathe M, Grütter C, Rabiller M, van Otterlo WAL, Rauh D. Fluorophore labeled kinase detects ligands that bind within the MAPK insert of p38α kinase. PLoS One 2012; 7:e39713. [PMID: 22768308 PMCID: PMC3388095 DOI: 10.1371/journal.pone.0039713] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2012] [Accepted: 05/25/2012] [Indexed: 11/19/2022] Open
Abstract
The vast majority of small molecules known to modulate kinase activity, target the highly conserved ATP-pocket. Consequently, such ligands are often less specific and in case of inhibitors, this leads to the inhibition of multiple kinases. Thus, selective modulation of kinase function remains a major hurdle. One of the next great challenges in kinase research is the identification of ligands which bind to less conserved sites and target the non-catalytic functions of protein kinases. However, approaches that allow for the unambiguous identification of molecules that bind to these less conserved sites are few in number. We have previously reported the use of fluorescent labels in kinases (FLiK) to develop direct kinase binding assays that exclusively detect ligands which stabilize inactive (DFG-out) kinase conformations. Here, we present the successful application of the FLiK approach to develop a high-throughput binding assay capable of directly monitoring ligand binding to a remote site within the MAPK insert of p38α mitogen-activated protein kinase (MAPK). Guided by the crystal structure of an initially identified hit molecule in complex with p38α, we developed a tight binding ligand which may serve as an ideal starting point for further investigations of the biological function of the MAPK insert in regulating the p38α signaling pathway.
Collapse
Affiliation(s)
- Matthäus Getlik
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Jeffrey R. Simard
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Martin Termathe
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Christian Grütter
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Fakultät Chemie, Chemische Biologie, Technische Universität Dortmund, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Matthias Rabiller
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
| | - Willem A. L. van Otterlo
- Department of Chemistry and Polymer Sciences, Stellenbosch University, Stellenbosch, South Africa
| | - Daniel Rauh
- Chemical Genomics Centre of the Max Planck Society, Dortmund, Germany
- Fakultät Chemie, Chemische Biologie, Technische Universität Dortmund, Dortmund, Germany
- Max-Planck-Institute of Molecular Physiology, Dortmund, Germany
- * E-mail:
| |
Collapse
|
138
|
Lewitzky M, Simister PC, Feller SM. Beyond 'furballs' and 'dumpling soups' - towards a molecular architecture of signaling complexes and networks. FEBS Lett 2012; 586:2740-50. [PMID: 22710161 DOI: 10.1016/j.febslet.2012.04.029] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Accepted: 04/16/2012] [Indexed: 12/14/2022]
Abstract
The molecular architectures of intracellular signaling networks are largely unknown. Understanding their design principles and mechanisms of processing information is essential to grasp the molecular basis of virtually all biological processes. This is particularly challenging for human pathologies like cancers, as essentially each tumor is a unique disease with vastly deranged signaling networks. However, even in normal cells we know almost nothing. A few 'signalosomes', like the COP9 and the TCR signaling complexes have been described, but detailed structural information on their architectures is largely lacking. Similarly, many growth factor receptors, for example EGF receptor, insulin receptor and c-Met, signal via huge protein complexes built on large platform proteins (Gab, Irs/Dok, p130Cas[BCAR1], Frs families etc.), which are structurally not well understood. Subsequent higher order processing events remain even more enigmatic. We discuss here methods that can be employed to study signaling architectures, and the importance of too often neglected features like macromolecular crowding, intrinsic disorder in proteins and the sophisticated cellular infrastructures, which need to be carefully considered in order to develop a more mature understanding of cellular signal processing.
Collapse
Affiliation(s)
- Marc Lewitzky
- Biological Systems Architecture Group, Weatherall Institute of Molecular Medicine, Department of Oncology, University of Oxford, Oxford OX3 9DS, United Kingdom.
| | | | | |
Collapse
|