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Yin Y, Liu Z, Li Q, Gou M, Han Y, Xu Y. Identification and evolution of PDK-1-like involving lamprey innate immunity. Mol Immunol 2024; 172:47-55. [PMID: 38875755 DOI: 10.1016/j.molimm.2024.06.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 12/02/2023] [Accepted: 06/01/2024] [Indexed: 06/16/2024]
Abstract
3-phosphoinositide-dependent protein kinase-1 (PDK-1) is a key kinase regulating the activity of the PI3K/AKT pathway and a major regulator of the AGC protein kinase family. It is essential in the physiological activities of cells, embryonic development, individual development and immune response. In this study, we have identified for the first time an analogue of PDK-1 in the most primitive vertebrate, lamprey, and named it PDK-1-like. The protein sequence similarity of lamprey PDK-1-like to human, mouse, chicken, African xenopus and zebrafish PDK-1 were 64.4 %, 64.5 %, 65.0 %, 61.3 % and 63.2 %, respectively. The phylogenetic tree showed that PDK-1-like of lamprey were located at the base of the vertebrate branch, in line with the trend of biological evolution. Meanwhile, homology analysis showed that PDK-1 proteins across species shared a conserved kinase structural domain and a Pleckstrin Homology (PH) domain. Genomic synteny analysis revealed that the large-scale duplication blocks were not found in lamprey genome and neighbor genes of lamprey PDK-1-like presented dramatic differences compared with jawed vertebrates. More importantly, qPCR analysis showed that PDK-1-like was widely expressed in lamprey. Its mRNA expression levels varied in response to different pathogenic stimuli, and its expression was generally up-regulated under Polyinosinic-Polycytidylic acid (Poly(I:C)) stimulation. Pearson's correlation analysis showed that PDK-1-like was involved in co-expressed with MyD88-independent TLR-3 pathway during the immune response of lamprey, instead of MyD88-dependent TLR-3 pathway. In summary, our composite results offer valuable clues to the origin and evolution of PDK-1, and imply that PDK-1 s are among the most ancestral immune regulators in vertebrates.
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Affiliation(s)
- Yi Yin
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Zhulin Liu
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Qingwei Li
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China
| | - Meng Gou
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China.
| | - Yinglun Han
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China.
| | - Yang Xu
- College of Life Sciences, Liaoning Normal University, Dalian, China; Lamprey Research Center, Liaoning Normal University, Dalian, China; Collaborative Innovation Center of Seafood Deep Processing, Dalian Polytechnic University, Dalian, China.
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Leroux AE, Biondi RM. The choreography of protein kinase PDK1 and its diverse substrate dance partners. Biochem J 2023; 480:1503-1532. [PMID: 37792325 DOI: 10.1042/bcj20220396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/24/2023] [Accepted: 08/31/2023] [Indexed: 10/05/2023]
Abstract
The protein kinase PDK1 phosphorylates at least 24 distinct substrates, all of which belong to the AGC protein kinase group. Some substrates, such as conventional PKCs, undergo phosphorylation by PDK1 during their synthesis and subsequently get activated by DAG and Calcium. On the other hand, other substrates, including members of the Akt/PKB, S6K, SGK, and RSK families, undergo phosphorylation and activation downstream of PI3-kinase signaling. This review presents two accepted molecular mechanisms that determine the precise and timely phosphorylation of different substrates by PDK1. The first mechanism involves the colocalization of PDK1 with Akt/PKB in the presence of PIP3. The second mechanism involves the regulated docking interaction between the hydrophobic motif (HM) of substrates and the PIF-pocket of PDK1. This interaction, in trans, is equivalent to the molecular mechanism that governs the activity of AGC kinases through their HMs intramolecularly. PDK1 has been instrumental in illustrating the bi-directional allosteric communication between the PIF-pocket and the ATP-binding site and the potential of the system for drug discovery. PDK1's interaction with substrates is not solely regulated by the substrates themselves. Recent research indicates that full-length PDK1 can adopt various conformations based on the positioning of the PH domain relative to the catalytic domain. These distinct conformations of full-length PDK1 can influence the interaction and phosphorylation of substrates. Finally, we critically discuss recent findings proposing that PIP3 can directly regulate the activity of PDK1, which contradicts extensive in vitro and in vivo studies conducted over the years.
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Affiliation(s)
- Alejandro E Leroux
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA) - CONICET - Partner Institute of the Max Planck Society, Buenos Aires C1425FQD, Argentina
| | - Ricardo M Biondi
- Instituto de Investigación en Biomedicina de Buenos Aires (IBioBA) - CONICET - Partner Institute of the Max Planck Society, Buenos Aires C1425FQD, Argentina
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Li H, Cheng L, Su S, Guo P, Wei Z. Pyruvate dehydrogenase kinase 1 regulates the function of human decidual natural killer cells. Am J Reprod Immunol 2023; 90:e13765. [PMID: 37766401 DOI: 10.1111/aji.13765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/24/2023] [Accepted: 08/01/2023] [Indexed: 09/29/2023] Open
Abstract
PROBLEM Pyruvate dehydrogenase kinase 1 (PDK1) is an important enzyme for immune cell development. However, PDK1's role in human decidual natural killer (dNK) cells remains largely unknown. METHODS OF STUDY PDK1 expression in dNK cells from patients with recurrent spontaneous abortions (RSA) and age-matched healthy controls was analyzed by qRT-PCR, western bolt and flow cytometry. Moreover, dNK cells were treated with PDK1 inhibitor or the PDK1 siRNA followed by functional assays. RESULTS The dNK cells from patients who underwent RSAs had higher mRNA expression and increased protein of PDK1, perforin (PRF1), Granzyme B (GZMB), IFN-γ (IFNG), and CD107a expression compared to dNK cells from age-matched healthy controls. Perforin, Granzyme B, IFN-γ and CD107a expression levels in dNK cells were down-regulated when dNK cells were treated with a PDK1 inhibitor. As measured by the 51 Cr release assay, the killing activity of dNK cells was found to be decreased. We also demonstrated that PDK1 blockade could up-regulate the migration and adhesion of dNK cells. Furthermore, PDK1 inhibition reduced the glycolysis of dNK cells. CONCLUSION This study suggested that PDK1 plays an important role in regulating dNK cell functions and human RSA.
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Affiliation(s)
- Huirong Li
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, Anhui Province, China
| | - Linghui Cheng
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, Anhui Province, China
| | - Shiyue Su
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, Anhui Province, China
| | - Peipei Guo
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, Anhui Province, China
| | - Zhaolian Wei
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Anhui Medical University, Anhui Province Key Laboratory of Reproductive Health and Genetics, Biopreservation and Artificial Organs, Anhui Provincial Engineering Research Center, Anhui Medical University, Hefei, Anhui Province, China
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Smith TA, Lopez-Perez GS, Herneisen AL, Shortt E, Lourido S. Screening the Toxoplasma kinome with high-throughput tagging identifies a regulator of invasion and egress. Nat Microbiol 2022; 7:868-881. [PMID: 35484233 PMCID: PMC9167752 DOI: 10.1038/s41564-022-01104-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Accepted: 03/11/2022] [Indexed: 12/26/2022]
Abstract
Protein kinases regulate fundamental aspects of eukaryotic cell biology, making them attractive chemotherapeutic targets in parasites like Plasmodium spp. and Toxoplasma gondii. To systematically examine the parasite kinome, we developed a high-throughput tagging (HiT) strategy to endogenously label protein kinases with an auxin-inducible degron and fluorophore. Hundreds of tagging vectors were assembled from synthetic sequences in a single reaction and used to generate pools of mutants to determine localization and function. Examining 1,160 arrayed clones, we assigned 40 protein localizations and associated 15 kinases with distinct defects. The fitness of tagged alleles was also measured by pooled screening, distinguishing delayed from acute phenotypes. A previously unstudied kinase, associated with a delayed phenotype, was shown to be a regulator of invasion and egress. We named the kinase Store Potentiating/Activating Regulatory Kinase (SPARK), based on its impact on intracellular Ca2+ stores. Despite homology to mammalian 3-phosphoinositide-dependent protein kinase-1 (PDK1), SPARK lacks a lipid-binding domain, suggesting a rewiring of the pathway in parasites. HiT screening extends genome-wide approaches into complex cellular phenotypes, providing a scalable and versatile platform to dissect parasite biology.
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Affiliation(s)
- Tyler A Smith
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | | | - Alice L Herneisen
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Emily Shortt
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, Cambridge, MA, USA.
- Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
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The Landscape of PDK1 in Breast Cancer. Cancers (Basel) 2022; 14:cancers14030811. [PMID: 35159078 PMCID: PMC8834120 DOI: 10.3390/cancers14030811] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 12/31/2021] [Indexed: 02/04/2023] Open
Abstract
Given that 3-phosphoinositide-dependent kinase 1 (PDK1) plays a crucial role in the malignant biological behaviors of a wide range of cancers, we review the influence of PDK1 in breast cancer (BC). First, we describe the power of PDK1 in cellular behaviors and characterize the interaction networks of PDK1. Then, we establish the roles of PDK1 in carcinogenesis, growth and survival, metastasis, and chemoresistance in BC cells. More importantly, we sort the current preclinical or clinical trials of PDK1-targeted therapy in BC and find that, even though no selective PDK1 inhibitor is currently available for BC therapy, the combination trials of PDK1-targeted therapy and other agents have provided some benefit. Thus, there is increasing anticipation that PDK1-targeted therapy will have its space in future therapeutic approaches related to BC, and we hope the novel approaches of targeted therapy will be conducive to ameliorating the dismal prognosis of BC patients.
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Hitz E, Wiedemar N, Passecker A, Graça BAS, Scheurer C, Wittlin S, Brancucci NMB, Vakonakis I, Mäser P, Voss TS. The 3-phosphoinositide-dependent protein kinase 1 is an essential upstream activator of protein kinase A in malaria parasites. PLoS Biol 2021; 19:e3001483. [PMID: 34879056 PMCID: PMC8687544 DOI: 10.1371/journal.pbio.3001483] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 12/20/2021] [Accepted: 11/12/2021] [Indexed: 01/11/2023] Open
Abstract
Cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) signalling is essential for the proliferation of Plasmodium falciparum malaria blood stage parasites. The mechanisms regulating the activity of the catalytic subunit PfPKAc, however, are only partially understood, and PfPKAc function has not been investigated in gametocytes, the sexual blood stage forms that are essential for malaria transmission. By studying a conditional PfPKAc knockdown (cKD) mutant, we confirm the essential role for PfPKAc in erythrocyte invasion by merozoites and show that PfPKAc is involved in regulating gametocyte deformability. We furthermore demonstrate that overexpression of PfPKAc is lethal and kills parasites at the early phase of schizogony. Strikingly, whole genome sequencing (WGS) of parasite mutants selected to tolerate increased PfPKAc expression levels identified missense mutations exclusively in the gene encoding the parasite orthologue of 3-phosphoinositide-dependent protein kinase-1 (PfPDK1). Using targeted mutagenesis, we demonstrate that PfPDK1 is required to activate PfPKAc and that T189 in the PfPKAc activation loop is the crucial target residue in this process. In summary, our results corroborate the importance of tight regulation of PfPKA signalling for parasite survival and imply that PfPDK1 acts as a crucial upstream regulator in this pathway and potential new drug target.
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Affiliation(s)
- Eva Hitz
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Natalie Wiedemar
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Armin Passecker
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Beatriz A. S. Graça
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Christian Scheurer
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Sergio Wittlin
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Nicolas M. B. Brancucci
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Ioannis Vakonakis
- Department of Biochemistry, University of Oxford, Oxford, United Kingdom
| | - Pascal Mäser
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
| | - Till S. Voss
- Department of Medical Parasitology and Infection Biology, Swiss Tropical and Public Health Institute, Basel, Switzerland
- University of Basel, Basel, Switzerland
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Xiao Y, Offringa R. PDK1 regulates auxin transport and Arabidopsis vascular development through AGC1 kinase PAX. NATURE PLANTS 2020; 6:544-555. [PMID: 32393878 DOI: 10.1038/s41477-020-0650-2] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 03/25/2020] [Indexed: 06/11/2023]
Abstract
The 3-phosphoinositide-dependent protein kinase 1 (PDK1) is a conserved master regulator of AGC kinases in eukaryotic organisms. pdk1 loss of function causes a lethal phenotype in animals and yeasts, but only mild phenotypic defects in Arabidopsis thaliana (Arabidopsis). The Arabidopsis genome contains two PDK1-encoding genes, PDK1 and PDK2. Here, we used clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) to generate true loss-of-function pdk1 alleles, which, when combined with pdk2 alleles, showed severe developmental defects including fused cotyledons, a short primary root, dwarf stature and defects in male fertility. We obtained evidence that PDK1 is responsible for AGC1 kinase PROTEIN KINASE ASSOCIATED WITH BRX (PAX) activation by phosphorylation during vascular development, and that the PDK1 phospholipid-binding Pleckstrin Homology domain is not required for this process. Our data indicate that PDK1 regulates polar auxin transport by activating AGC1 clade kinases, resulting in PIN phosphorylation.
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Affiliation(s)
- Yao Xiao
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, the Netherlands
- Plant Systems Biology, TUM School of Life Sciences Weihenstephan, Technical University of Munich, Freising, Germany
| | - Remko Offringa
- Plant Developmental Genetics, Institute of Biology Leiden, Leiden University, Leiden, the Netherlands.
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Gagliardi PA, Puliafito A, Primo L. PDK1: At the crossroad of cancer signaling pathways. Semin Cancer Biol 2018; 48:27-35. [DOI: 10.1016/j.semcancer.2017.04.014] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/28/2017] [Accepted: 04/26/2017] [Indexed: 12/28/2022]
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Yang Y, Kong W, Xia Z, Xiao L, Wang S. Regulation mechanism of PDK1 on macrophage metabolism and function. Cell Biochem Funct 2016; 34:546-553. [DOI: 10.1002/cbf.3235] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 09/11/2016] [Accepted: 10/11/2016] [Indexed: 01/21/2023]
Affiliation(s)
- Yueqin Yang
- Exercise Intervention and Health Promotion Hubei Province Synergy Innovation Center; Wuhan Sports University; Wuhan Hubei China
| | - Weiwei Kong
- Graduate School; Wuhan Sports University; Wuhan Hubei China
| | - Zhi Xia
- Exercise Physiology and Biochemical Laboratory, College of Physical Education; Jinggangshan University; Ji'an Jiangxi China
| | - Lin Xiao
- School of Physical Education and Health Science; Zhaoqing University; Zhaoqing Guangdong China
| | - Song Wang
- Exercise Intervention and Health Promotion Hubei Province Synergy Innovation Center; Wuhan Sports University; Wuhan Hubei China
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10
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PDK1: A signaling hub for cell migration and tumor invasion. Biochim Biophys Acta Rev Cancer 2015; 1856:178-88. [DOI: 10.1016/j.bbcan.2015.07.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 07/28/2015] [Indexed: 01/22/2023]
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Zhou X, Cordon-Barris L, Zurashvili T, Bayascas JR. Fine-tuning the intensity of the PKB/Akt signal enables diverse physiological responses. Cell Cycle 2015; 13:3164-8. [PMID: 25485494 DOI: 10.4161/15384101.2014.962954] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The PI3K/PDK1/PKB signaling pathway plays essential roles in regulating neuronal survival, differentiation and plasticity in response to neurotrophic factors, neurotransmitters and ion channels. Both PDK1 and PKB can interact at the plasma membrane with a phosphoinositide synthesized by PI3K, the second messenger PtdIns(3,4,5)P3, enabling PDK1 to phosphorylate and activate PKB. In the PDK1 K465E knock-in mice expressing a mutant form of PDK1 incapable of phosphoinositide binding, activation of PKB was markedly affected, but not totally abolished. It has been recently proposed that in the absence of PtdIns(3,4,5)P3 binding, PDK1 can still moderately activate PKB due to a docking site-mediated interaction of these 2 kinases. A recent report has uncovered that in the PDK1 K465E mice neurons, a PKB signal threshold was sufficient to support neuronal survival responses, whereas neuritogenesis, neuronal polarization and axon outgrowth were severely impaired. We propose here that the low-efficiency mechanism of PKB activation observed in the PDK1 K465E mice might represent the ancestral mechanism responsible for the essential functions of this pathway, while the phosphoinositide-dependent activation should be considered an evolutionary innovation that enabled the acquisition of novel functions.
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Affiliation(s)
- Xiangyu Zhou
- a Institut de Neurociències & Departament de Bioquímica i Biologia Molecular ; Universitat Autònoma de Barcelona ; Barcelona , Spain
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Hindle MM, Martin SF, Noordally ZB, van Ooijen G, Barrios-Llerena ME, Simpson TI, Le Bihan T, Millar AJ. The reduced kinome of Ostreococcus tauri: core eukaryotic signalling components in a tractable model species. BMC Genomics 2014; 15:640. [PMID: 25085202 PMCID: PMC4143559 DOI: 10.1186/1471-2164-15-640] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Accepted: 07/08/2014] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND The current knowledge of eukaryote signalling originates from phenotypically diverse organisms. There is a pressing need to identify conserved signalling components among eukaryotes, which will lead to the transfer of knowledge across kingdoms. Two useful properties of a eukaryote model for signalling are (1) reduced signalling complexity, and (2) conservation of signalling components. The alga Ostreococcus tauri is described as the smallest free-living eukaryote. With less than 8,000 genes, it represents a highly constrained genomic palette. RESULTS Our survey revealed 133 protein kinases and 34 protein phosphatases (1.7% and 0.4% of the proteome). We conducted phosphoproteomic experiments and constructed domain structures and phylogenies for the catalytic protein-kinases. For each of the major kinases families we review the completeness and divergence of O. tauri representatives in comparison to the well-studied kinomes of the laboratory models Arabidopsis thaliana and Saccharomyces cerevisiae, and of Homo sapiens. Many kinase clades in O. tauri were reduced to a single member, in preference to the loss of family diversity, whereas TKL and ABC1 clades were expanded. We also identified kinases that have been lost in A. thaliana but retained in O. tauri. For three, contrasting eukaryotic pathways - TOR, MAPK, and the circadian clock - we established the subset of conserved components and demonstrate conserved sites of substrate phosphorylation and kinase motifs. CONCLUSIONS We conclude that O. tauri satisfies our two central requirements. Several of its kinases are more closely related to H. sapiens orthologs than S. cerevisiae is to H. sapiens. The greatly reduced kinome of O. tauri is therefore a suitable model for signalling in free-living eukaryotes.
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Affiliation(s)
| | | | | | | | | | | | | | - Andrew J Millar
- SynthSys and School of Biological Sciences, University of Edinburgh, Edinburgh EH9 3JD, UK.
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Arencibia JM, Pastor-Flores D, Bauer AF, Schulze JO, Biondi RM. AGC protein kinases: from structural mechanism of regulation to allosteric drug development for the treatment of human diseases. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2013; 1834:1302-21. [PMID: 23524293 DOI: 10.1016/j.bbapap.2013.03.010] [Citation(s) in RCA: 121] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 03/07/2013] [Indexed: 01/15/2023]
Abstract
The group of AGC protein kinases includes more than 60 protein kinases in the human genome, classified into 14 families: PDK1, AKT/PKB, SGK, PKA, PKG, PKC, PKN/PRK, RSK, NDR, MAST, YANK, DMPK, GRK and SGK494. This group is also widely represented in other eukaryotes, including causative organisms of human infectious diseases. AGC kinases are involved in diverse cellular functions and are potential targets for the treatment of human diseases such as cancer, diabetes, obesity, neurological disorders, inflammation and viral infections. Small molecule inhibitors of AGC kinases may also have potential as novel therapeutic approaches against infectious organisms. Fundamental in the regulation of many AGC kinases is a regulatory site termed the "PIF-pocket" that serves as a docking site for substrates of PDK1. This site is also essential to the mechanism of activation of AGC kinases by phosphorylation and is involved in the allosteric regulation of N-terminal domains of several AGC kinases, such as PKN/PRKs and atypical PKCs. In addition, the C-terminal tail and its interaction with the PIF-pocket are involved in the dimerization of the DMPK family of kinases and may explain the molecular mechanism of allosteric activation of GRKs by GPCR substrates. In this review, we briefly introduce the AGC kinases and their known roles in physiology and disease and the discovery of the PIF-pocket as a regulatory site in AGC kinases. Finally, we summarize the current status and future therapeutic potential of small molecules directed to the PIF-pocket; these molecules can allosterically activate or inhibit the kinase as well as act as substrate-selective inhibitors. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases (2012).
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Affiliation(s)
- José M Arencibia
- Research Group PhosphoSites, Department of Internal Medicine I, Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany
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