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Ohtsuka S, Miyai Y, Mima H, Magari M, Chiba Y, Suizu F, Sakagami H, Ueno M, Tokumitsu H. Transcriptional, biochemical, and immunohistochemical analyses of CaMKKβ/2 splice variants that co-localize with CaMKIV in spermatids. Cell Calcium 2024; 117:102820. [PMID: 37979343 DOI: 10.1016/j.ceca.2023.102820] [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: 07/28/2023] [Revised: 10/18/2023] [Accepted: 10/29/2023] [Indexed: 11/20/2023]
Abstract
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) phosphorylates and activates downstream protein kinases, including CaMKI, CaMKIV, PKB/Akt, and AMPK; thus, regulates various Ca2+-dependent physiological and pathophysiological pathways. Further, CaMKKβ/2 in mammalian species comprises multiple alternatively spliced variants; however, their functional differences or redundancy remain unclear. In this study, we aimed to characterize mouse CaMKKβ/2 splice variants (CaMKKβ-3 and β-3x). RT-PCR analyses revealed that mouse CaMKKβ-1, consisting of 17 exons, was predominantly expressed in the brain; whereas, mouse CaMKKβ-3 and β-3x, lacking exon 16 and exons 14/16, respectively, were primarily expressed in peripheral tissues. At the protein level, the CaMKKβ-3 or β-3x variants showed high expression levels in mouse cerebrum and testes. This was consistent with the localization of CaMKKβ-3/-3x in spermatids in seminiferous tubules, but not the localization of CaMKKβ-1. We also observed the co-localization of CaMKKβ-3/-3x with a target kinase, CaMKIV, in elongating spermatids. Biochemical characterization further revealed that CaMKKβ-3 exhibited Ca2+/CaM-induced kinase activity similar to CaMKKβ-1. Conversely, we noted that CaMKKβ-3x impaired Ca2+/CaM-binding ability, but exhibited significantly weak autonomous activity (approximately 500-fold lower than CaMKKβ-1 or β-3) due to the absence of C-terminal of the catalytic domain and a putative residue (Ile478) responsible for the kinase autoinhibition. Nevertheless, CaMKKβ-3x showed the ability to phosphorylate downstream kinases, including CaMKIα, CaMKIV, and AMPKα in transfected cells comparable to CaMKKβ-1 and β-3. Collectively, CaMKKβ-3/-3x were identified as functionally active and could be bona fide CaMKIV-kinases in testes involved in the activation of the CaMKIV cascade in spermatids, resulting in the regulation of spermiogenesis.
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Affiliation(s)
- Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Yumi Miyai
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroyuki Mima
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan
| | - Yoichi Chiba
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Futoshi Suizu
- Oncology Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Kanagawa, 252-0374, Japan
| | - Masaki Ueno
- Inflammation Pathology, Department of Pathology and Host Defense, Faculty of Medicine, Kagawa University, Kagawa, 761-0793, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama, 700-8530, Japan.
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The role of CaMKK2 in Golgi-associated vesicle trafficking. Biochem Soc Trans 2023; 51:331-342. [PMID: 36815702 PMCID: PMC9987998 DOI: 10.1042/bst20220833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 02/03/2023] [Accepted: 02/07/2023] [Indexed: 02/24/2023]
Abstract
Calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) is a serine/threonine-protein kinase, that is involved in maintaining various physiological and cellular processes within the cell that regulate energy homeostasis and cell growth. CaMKK2 regulates glucose metabolism by the activation of downstream kinases, AMP-activated protein kinase (AMPK) and other calcium/calmodulin-dependent protein kinases. Consequently, its deregulation has a role in multiple human metabolic diseases including obesity and cancer. Despite the importance of CaMKK2, its signalling pathways and pathological mechanisms are not completely understood. Recent work has been aimed at broadening our understanding of the biological functions of CaMKK2. These studies have uncovered new interaction partners that have led to the description of new functions that include lipogenesis and Golgi vesicle trafficking. Here, we review recent insights into the role of CaMKK2 in membrane trafficking mechanisms and discuss the functional implications in a cellular context and for disease.
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Potential role for protein kinase D inhibitors in prostate cancer. J Mol Med (Berl) 2023; 101:341-349. [PMID: 36843036 DOI: 10.1007/s00109-023-02298-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Revised: 02/01/2023] [Accepted: 02/10/2023] [Indexed: 02/28/2023]
Abstract
Protein kinase D (PrKD), a novel serine-threonine kinase, belongs to a family of calcium calmodulin kinases that consists of three isoforms: PrKD1, PrKD2, and PrKD3. The PrKD isoforms play a major role in pathologic processes such as cardiac hypertrophy and cancer progression. The charter member of the family, PrKD1, is the most extensively studied isoform. PrKD play a dual role as both a proto-oncogene and a tumor suppressor depending on the cellular context. The duplicity of PrKD can be highlighted in advanced prostate cancer (PCa) where expression of PrKD1 is suppressed whereas the expressions of PrKD2 and PrKD3 are upregulated to aid in cancer progression. As understanding of the PrKD signaling pathways has been better elucidated, interest has been garnered in the development of PrKD inhibitors. The broad-spectrum kinase inhibitor staurosporine acts as a potent PrKD inhibitor and is the most well-known; however, several other novel and more specific PrKD inhibitors have been developed over the last two decades. While there is tremendous potential for PrKD inhibitors to be used in a clinical setting, none has progressed beyond preclinical trials due to a variety of challenges. In this review, we focus on PrKD signaling in PCa and the potential role of PrKD inhibitors therein, and explore the possible clinical outcomes based on known function and expression of PrKD isoforms at different stages of PCa.
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Li J, Wang X, Meng X, Zhou X, Huang H, Feng Y, Fu Y, Liu X, Yu B. Geraniin targeting CaMKK2 inhibits lipid accumulation in 3T3-L1 adipocytes by suppressing lipogenesis. Chem Biol Interact 2023; 372:110364. [PMID: 36706894 DOI: 10.1016/j.cbi.2023.110364] [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: 09/19/2022] [Revised: 11/08/2022] [Accepted: 01/23/2023] [Indexed: 01/27/2023]
Abstract
Obesity has become a worldwide burden and is associated with severe medical complications. Geraniin is a polyphenolic compound that has a wide range of bioactive properties. There is also evidence to support its pharmacological effects on improving lipid accumulation and obesity. This research investigates the effect of geraniin on lipid accumulation in adipocytes and the underlying mechanism. Mature adipocytes were differentiated from immature 3T3-L1 cells. Oil Red O staining and a triglyceride content determination were conducted to evaluate the intracellular lipid accumulation. Molecular docking studies were performed to determine the interaction between geraniin and the key proteins. Western blotting was used to detect the expression of lipogenic enzymes and transcription factors. Geraniin dose-dependently inhibited lipid accumulation in adipocytes by reducing the expression of fatty acid synthase and increasing the phosphorylation level of acetyl-coenzyme A carboxylase. Moreover, geraniin promoted the phosphorylation of AMP-activated protein kinase (AMPK) and further reduced the expression of lipogenic transcription factors (peroxisome proliferator-activated receptor gamma and CCAAT/enhancer binding protein alpha). The expression of the calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) was increased by the geraniin administration. The molecular docking study demonstrated that geraniin can interact with CaMKK2, which is an upstream kinase of AMPK. A selective CaMKK2 inhibitor reversed the suppressive effect of geraniin on lipogenesis. Geraniin targeted CaMKK2 to inhibit lipid accumulation in 3T3-L1 adipocytes by suppressing lipogenesis, and this supports its potential as a candidate natural anti-obesity drug.
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Affiliation(s)
- Ji Li
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
| | - Xuedong Wang
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
| | - Xiangyu Meng
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
| | - Xin Zhou
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
| | - Han Huang
- College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin, 150040, PR China
| | - Yi Feng
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
| | - Yujie Fu
- College of Chemistry, Chemical Engineering and Resource Utilization, Northeast Forestry University, Harbin, 150040, PR China
| | - Xinxin Liu
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China.
| | - Bo Yu
- Department of Cardiology, 2nd Affiliated Hospital of Harbin Medical University, Harbin, 150001, China; Key Laboratory of Myocardial Ischemia, Ministry of Education, Harbin Medical University, Harbin, 150001, China
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Gómez-Pinedo U, Torre-Fuentes L, Matías-Guiu JA, Pytel V, Ojeda-Hernández DD, Selma-Calvo B, Montero-Escribano P, Vidorreta-Ballesteros L, Matías-Guiu J. Exonic variants of the P2RX7 gene in familial multiple sclerosis. Neurologia 2022:S2173-5808(22)00189-4. [PMID: 36470550 DOI: 10.1016/j.nrleng.2022.12.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 10/09/2022] [Indexed: 12/12/2022] Open
Abstract
INTRODUCTION Several studies have analysed the presence of P2RX7 variants in patients with MS, reporting diverging results. METHODS Our study analyses P2RX7 variants detected through whole-exome sequencing (WES). RESULTS We analysed P2RX7, P2RX4, and CAMKK2 gene variants detected by whole-exome sequencing in all living members (n = 127) of 21 families including at least 2 individuals with multiple sclerosis. P2RX7 gene polymorphisms previously associated with autoimmune disease. Although no differences were observed between individuals with and without multiple sclerosis, we found greater polymorphism of gain-of-function variants of P2RX7 in families with individuals with multiple sclerosis than in the general population. Copresence of gain-of-function and loss-of-function variants was not observed to reduce the risk of presenting the disease. Three families displayed heterozygous gain-of-function SNPs in patients with multiple sclerosis but not in healthy individuals. We were unable to determine the impact of copresence of P2RX4 and CAMKK2 variants with P2RX7 variants, or the potential effect of the different haplotypes described in the gene. No clinical correlations with other autoimmune diseases were observed in our cohort. CONCLUSIONS Our results support the hypothesis that the disease is polygenic and point to a previously unknown mechanism of genetic predisposition to familial forms of multiple sclerosis. P2RX7 gene activity can be modified, which suggests the possibility of preventive pharmacological treatments for families including patients with familial multiple sclerosis.
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Affiliation(s)
- U Gómez-Pinedo
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain.
| | - L Torre-Fuentes
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - J A Matías-Guiu
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - V Pytel
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain; Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - D D Ojeda-Hernández
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - B Selma-Calvo
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - P Montero-Escribano
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - L Vidorreta-Ballesteros
- Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
| | - J Matías-Guiu
- Laboratory of Neurobiology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain; Department of Neurology, Institute of Neurosciences, IdISSC, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid, Spain
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Molecular Mechanisms Underlying Ca2+/Calmodulin-Dependent Protein Kinase Kinase Signal Transduction. Int J Mol Sci 2022; 23:ijms231911025. [PMID: 36232320 PMCID: PMC9570080 DOI: 10.3390/ijms231911025] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/16/2022] [Accepted: 09/16/2022] [Indexed: 12/03/2022] Open
Abstract
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) is the activating kinase for multiple downstream kinases, including CaM-kinase I (CaMKI), CaM-kinase IV (CaMKIV), protein kinase B (PKB/Akt), and 5′AMP-kinase (AMPK), through the phosphorylation of their activation-loop Thr residues in response to increasing the intracellular Ca2+ concentration, as CaMKK itself is a Ca2+/CaM-dependent enzyme. The CaMKK-mediated kinase cascade plays important roles in a number of Ca2+-dependent pathways, such as neuronal morphogenesis and plasticity, transcriptional activation, autophagy, and metabolic regulation, as well as in pathophysiological pathways, including cancer progression, metabolic syndrome, and mental disorders. This review focuses on the molecular mechanism underlying CaMKK-mediated signal transduction in normal and pathophysiological conditions. We summarize the current knowledge of the structural, functional, and physiological properties of the regulatory kinase, CaMKK, and the development and application of its pharmacological inhibitors.
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Dai S, Venturini E, Yadav S, Lin X, Clapp D, Steckiewicz M, Gocher-Demske AM, Hardie DG, Edelman AM. Calcium/calmodulin-dependent protein kinase kinase 2 mediates pleiotropic effects of epidermal growth factor in cancer cells. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2022; 1869:119252. [PMID: 35271909 DOI: 10.1016/j.bbamcr.2022.119252] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 02/11/2022] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
AIMS Engagement of epidermal growth factor (EGF) with its receptor (EGFR) produces a broad range of cancer phenotypes. The overriding aim of this study was to understand EGFR signaling and its regulation by the Ca2+/calmodulin (CaM) dependent protein kinase kinase 2 (CaMKK2) in cancer cells. RESULTS In ovarian cancer cells and other cancer cell types, EGF-induced activation of oncogenic Akt is mediated by both the canonical PI3K-PDK1 pathway and by CaMKK2. Akt activation induced by EGF occurs by both calcium-dependent and calcium-independent mechanisms. In contrast to the canonical pathway, CaMKK2 neither binds to, nor is regulated by phosphoinositides but is activated by Ca2+/CaM. Akt activation at its primary activation site, T308 occurs by direct phosphorylation by CaMKK2, but activation at its secondary site (S473), is through an indirect mechanism requiring mTORC2. In cells in which another CaMKK2 target, 5'AMP-dependent protein kinase (AMPK) was deleted, Akt activation and calcium-dependency of activation were still observed. CaMKK2 accumulates in the nucleus in response to EGF and regulates transcription of phosphofructokinase platelet (PFKP) a glycolytic regulator. CaMKK2 is required for optimal PFK activity. CaMKK2 regulates transcription of plasminogen activator, urokinase (PLAU) a metastasis regulator. The EGFR inhibitor gefitinib synergizes with CaMKK2 inhibition in the regulation of cell survival and increases the dose-reduction index. CRISPR/Cas9 knockout of CaMKK2 leads to compensatory PTEN downregulation and upregulation of Akt activation. CONCLUSIONS CaMKK2-mediation of EGFR action may enable cancer cells to use intracellular calcium elevation as a signal for growth and survival.
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Affiliation(s)
- Shuhang Dai
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Elisa Venturini
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Saveg Yadav
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Xiaoxuan Lin
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Dylan Clapp
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Martin Steckiewicz
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America
| | - Angela M Gocher-Demske
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America; Department of Immunology School of Medicine, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 1521, United States of America
| | - D Grahame Hardie
- Division of Cell Signaling & Immunology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Arthur M Edelman
- Department of Pharmacology and Toxicology, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY 14203, United States of America.
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Abstract
In 2011, CAMKK2, the gene encoding calcium/calmodulin-dependent kinase kinase 2 (CAMKK2), was demonstrated to be a direct target of the androgen receptor and a driver of prostate cancer progression. Results from multiple independent studies have confirmed these findings and demonstrated the potential role of CAMKK2 as a clinical biomarker and therapeutic target in advanced prostate cancer using a variety of preclinical models. Drug development efforts targeting CAMKK2 have begun accordingly. CAMKK2 regulation can vary across disease stages, which might have important implications in the use of CAMKK2 as a biomarker. Moreover, new non-cell-autonomous roles for CAMKK2 that could affect tumorigenesis, metastasis and possible comorbidities linked to disease and treatment have emerged and could present novel treatment opportunities for prostate cancer.
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Zhou X, Guo W, Yin H, Chen J, Ma L, Yang Q, Zhao Y, Li S, Liu W, Li H. Whole Exome Sequencing Study in a Family with Type 2 Diabetes Mellitus. Int J Gen Med 2021; 14:8217-8229. [PMID: 34815695 PMCID: PMC8605871 DOI: 10.2147/ijgm.s335090] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 10/01/2021] [Indexed: 12/25/2022] Open
Abstract
Background Type 2 diabetes mellitus (T2DM) is characterized by β cell decline in the pancreas and insulin resistance. This study aimed to investigate the possible pathogenic gene mutation sites of T2DM patients using whole exome sequencing. Materials and Methods We recruited a Chinese family with 3-generation history of diabetes. The whole blood genomic DNA of seven members of the family was extracted and sent for whole exome sequencing. Biological information was analyzed with in silico prediction methods, including significance analysis of single nucleotide polymorphism (SNP)/Indel site, and analysis of specific SNP/Indel proteins and their potential mechanisms. Results Six out of seven members of the family were diagnosed with diabetes. All DNA samples (23 kb) met quality requirements of library construction. Clean reads of each sample demonstrated high Q20 and Q30 (>80%), indicating good sequencing quality of sequencing data. A total of 130,693 SNPs and 15,928 Indels were found in DNA samples. A total of 22 significant SNPs and Indel mutation sites located on 19 genes were obtained, including ZCCHC3, SYN2, RPL14, SRRD, AMD1, CAMKK2, ZNF787, RNF157, NPIPB15, ALG3, KIAA0040, MAST2, ESRRA, C8orf58, PNLIPRP1, DACH1, MACC1, CAPN9 and DMKN. An rs2305205 mutation of PNLIPRP1 gene and an rs778701848 mutation of CAMKK2 gene may be associated with the pathogenesis of T2DM in this family. Conclusion Exons of these diabetic patients demonstrated an rs2305205 mutation in PNLIPRP1 gene and an rs778701848 mutation in CAMKK2 gene. These two mutations might promote T2DM occurrence through reducing sensitivity of peripheral tissue to insulin and reducing insulin secretion.
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Affiliation(s)
- Xiaowei Zhou
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Weichang Guo
- Department of Physical Education, Kunming Medical University, Kunming, People's Republic of China
| | - Hejia Yin
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Jie Chen
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Liju Ma
- Department of Clinical Laboratory, First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Qiuping Yang
- Department of Geriatrics, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Yan Zhao
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Shaoyou Li
- Department of NHC Key Laboratory of Drug Addiction Medicine, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Weijun Liu
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
| | - Huifang Li
- Department of Diabetes, The First Affiliated Hospital of Kunming Medical University, Kunming, People's Republic of China
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A complete map of the Calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) signaling pathway. J Cell Commun Signal 2020; 15:283-290. [PMID: 33136287 DOI: 10.1007/s12079-020-00592-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Accepted: 10/19/2020] [Indexed: 12/16/2022] Open
Abstract
Calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) is a serine/threonine-protein kinase belonging to the Ca2+/calmodulin-dependent protein kinase subfamily. CAMKK2 has an autocatalytic site, which gets exposed when Ca2+/calmodulin (CAM) binds to it. This results in autophosphorylation and complete activation of CAMKK2. The three major known downstream targets of CAMKK2 are 5'-adenosine monophosphate (AMP)-activated protein kinase (AMPKα), calcium/calmodulin-dependent protein kinase 1 (CAMK1) and calcium/calmodulin-dependent protein kinase 4 (CAMK4). Activation of these targets by CAMKK2 is important for the maintenance of different cellular and physiological processes within the cell. CAMKK2 is found to be important in neuronal development, bone remodeling, adipogenesis, and systemic glucose homeostasis, osteoclastgensis and postnatal myogensis. CAMKK2 is reported to be involved in pathologies like Duchenne muscular dystrophy, inflammation, osteoporosis and bone remodeling and is also reported to be overexpressed in prostate cancer, hepatic cancer, ovarian and gastric cancer. CAMKK2 is involved in increased cell proliferation and migration through CAMKK2/AMPK pathway in prostate cancer and activation of AKT in ovarian cancer. Although CAMKK2 is a molecule of great importance, a public resource of the CAMKK2 signaling pathway is currently lacking. Therefore, we carried out detailed data mining and documentation of the signaling events associated with CAMKK2 from published literature and developed an integrated reaction map of CAMKK2 signaling. This resulted in the cataloging of 285 reactions belonging to the CAMKK2 signaling pathway, which includes 33 protein-protein interactions, 74 post-translational modifications, 7 protein translocation events, and 22 activation/inhibition events. Besides, 124 gene regulation events and 25 activator/inhibitors involved in CAMKK2 activation were also cataloged. The CAMKK2 signaling pathway map data is made freely accessible through WikiPathway database ( https://www.wikipathways.org/index.php/Pathway:WP4874 ). We expect that data on a signaling map of CAMKK2 will provide the scientific community with an improved platform to facilitate further molecular as well as biomedical investigations on CAMKK2 and its utility in the development of biomarkers and therapeutic targets.
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Sabbir MG, Taylor CG, Zahradka P. Hypomorphic CAMKK2 in EA.hy926 endothelial cells causes abnormal transferrin trafficking, iron homeostasis and glucose metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1867:118763. [DOI: 10.1016/j.bbamcr.2020.118763] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 05/23/2020] [Accepted: 05/27/2020] [Indexed: 02/08/2023]
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Dunn DM, Munger J. Interplay Between Calcium and AMPK Signaling in Human Cytomegalovirus Infection. Front Cell Infect Microbiol 2020; 10:384. [PMID: 32850483 PMCID: PMC7403205 DOI: 10.3389/fcimb.2020.00384] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/23/2020] [Indexed: 12/13/2022] Open
Abstract
Calcium signaling and the AMP-activated protein kinase (AMPK) signaling networks broadly regulate numerous aspects of cell biology. Human Cytomegalovirus (HCMV) infection has been found to actively manipulate the calcium-AMPK signaling axis to support infection. Many HCMV genes have been linked to modulating calcium signaling, and HCMV infection has been found to be reliant on calcium signaling and AMPK activation. Here, we focus on the cell biology of calcium and AMPK signaling and what is currently known about how HCMV modulates these pathways to support HCMV infection and potentially contribute to oncomodulation.
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Affiliation(s)
- Diana M Dunn
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, United States
| | - Joshua Munger
- Department of Biochemistry and Biophysics, School of Medicine and Dentistry, University of Rochester, Rochester, NY, United States
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Sabbir MG. CAMKK2-CAMK4 signaling regulates transferrin trafficking, turnover, and iron homeostasis. Cell Commun Signal 2020; 18:80. [PMID: 32460794 PMCID: PMC7251913 DOI: 10.1186/s12964-020-00575-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Accepted: 04/02/2020] [Indexed: 12/20/2022] Open
Abstract
Background Circulatory iron is a hazardous biometal. Therefore, iron is transported in a redox-safe state by a serum glycoprotein - transferrin (TF). Different organs acquire iron from the systemic circulation through a tightly regulated mechanism at the blood-tissue interface which involves receptor-mediated internalization of TF. Thus, abnormal TF trafficking may lead to iron dyshomeostasis associated with several diseases including neurodegeneration. Iron -induced toxicity can cause neuronal damage to iron-sensitive brain regions. Recently, it was discovered that CAMKK2, a calcium (Ca2+)/calmodulin-activated kinase, controls receptor-mediated TF trafficking in mouse tissues, specifically in the brain. The biological function of CAMKK2 is mediated through multiple downstream effectors. Both CAMKK2 and one of its downstream kinase, CAMK4, exhibit overlapping expression in mouse brain. The role of CAMK4 in vesicular transport has been reported and loss of CAMKK2 or CAMK4 leads to cognitive defects in mouse. Therefore, it was hypothesized that CAMKK2-CAMK4 signaling regulates receptor-mediated TF trafficking and iron homeostasis which may be responsible for the neuronal malfunction observed in CAMKK2- or CAMK4-deficient mice. Methods CAMK4−/− mouse was used to study tissue-specific turnover of TF, TF-receptor (TFRC) and iron. CRISPR/Cas9-based CAMKK2 and/or CAMK4 deleted human embryonic kidney-derived HEK293 cell clones were used to study the molecular defects in receptor-mediated TF trafficking. Further, a “zero functional G protein” condition in HEK293 cell was exploited to study CAMKK2-CAMK4 signaling-mediated regulation of intracellular Ca2+ homeostasis which was linked to calcium signaling during TF trafficking. Results Loss of CAMK4 leads to abnormal post-translational modifications (PTMs) and turnover of TF in mouse cerebellum and liver which was associated with iron dyshomeostasis in these tissues. The HEK293 cell-based study revealed that the absence of CAMKK2-CAMK4 signaling altered intracellular Ca2+ homeostasis and lead to abnormal calcium signaling during TF trafficking. Also, CAMKK2-CAMK4 signaling deficiency affected the molecular interaction of TF and TF-receptor-associated protein complexes which indicated a potential failure in the recruitment of interacting proteins due to differential PTMs in TF. Conclusion Overall, this study established a novel mechanistic link between intracellular Ca2+ level, receptor-mediated TF trafficking, and iron homeostasis, all regulated by CAMKK2-CAMK4 signaling. Video Abstract
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Affiliation(s)
- Mohammad Golam Sabbir
- Canadian Centre for Agri-Food Research in Health and Medicine, St. Boniface Albrechtsen Research Centre, Room R2034 - 351 Taché Avenue, Winnipeg, MB, R2H 2A6, Canada. .,Alzo Biosciences Inc., San Diego, CA, USA.
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14
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O’Byrne SN, Scott JW, Pilotte JR, Santiago ADS, Langendorf CG, Oakhill JS, Eduful BJ, Couñago RM, Wells CI, Zuercher WJ, Willson TM, Drewry DH. In Depth Analysis of Kinase Cross Screening Data to Identify CAMKK2 Inhibitory Scaffolds. Molecules 2020; 25:E325. [PMID: 31941153 PMCID: PMC7024175 DOI: 10.3390/molecules25020325] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 01/07/2020] [Accepted: 01/08/2020] [Indexed: 12/25/2022] Open
Abstract
The calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) activates CAMK1, CAMK4, AMPK, and AKT, leading to numerous physiological responses. The deregulation of CAMKK2 is linked to several diseases, suggesting the utility of CAMKK2 inhibitors for oncological, metabolic and inflammatory indications. In this work, we demonstrate that STO-609, frequently described as a selective inhibitor for CAMKK2, potently inhibits a significant number of other kinases. Through an analysis of literature and public databases, we have identified other potent CAMKK2 inhibitors and verified their activities in differential scanning fluorimetry and enzyme inhibition assays. These inhibitors are potential starting points for the development of selective CAMKK2 inhibitors and will lead to tools that delineate the roles of this kinase in disease biology.
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Affiliation(s)
- Sean N. O’Byrne
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - John W. Scott
- St Vincent’s Institute and Department of Medicine, The University of Melbourne, 41 Victoria Parade, Fitzroy 3065, Australia; (J.W.S.); (C.G.L.); (J.S.O.)
- Mary MacKillop Institute for Health Research, Australian Catholic University, 215 Spring Street, Melbourne 3000, Australia
- The Florey Institute of Neuroscience and Mental Health, 30 Royal Parade, Parkville 3052, Australia
| | - Joseph R. Pilotte
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - André da S. Santiago
- Centro de Química Medicinal (CQMED), Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas (UNICAMP), Campinas SP 13083-875, Brazil; (A.d.S.S.); (R.M.C.)
- Structural Genomics Consortium, Departamento de Genética e Evolução, Instituto de Biologia, UNICAMP, Campinas SP 13083-886, Brazil
| | - Christopher G. Langendorf
- St Vincent’s Institute and Department of Medicine, The University of Melbourne, 41 Victoria Parade, Fitzroy 3065, Australia; (J.W.S.); (C.G.L.); (J.S.O.)
| | - Jonathan S. Oakhill
- St Vincent’s Institute and Department of Medicine, The University of Melbourne, 41 Victoria Parade, Fitzroy 3065, Australia; (J.W.S.); (C.G.L.); (J.S.O.)
- Mary MacKillop Institute for Health Research, Australian Catholic University, 215 Spring Street, Melbourne 3000, Australia
| | - Benjamin J. Eduful
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - Rafael M. Couñago
- Centro de Química Medicinal (CQMED), Centro de Biologia Molecular e Engenharia Genética (CBMEG), Universidade Estadual de Campinas (UNICAMP), Campinas SP 13083-875, Brazil; (A.d.S.S.); (R.M.C.)
- Structural Genomics Consortium, Departamento de Genética e Evolução, Instituto de Biologia, UNICAMP, Campinas SP 13083-886, Brazil
| | - Carrow I. Wells
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - William J. Zuercher
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - Timothy M. Willson
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
| | - David H. Drewry
- Structural Genomics Consortium, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; (S.N.O.); (J.R.P.); (B.J.E.); (C.I.W.); (W.J.Z.); (T.M.W.)
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15
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Regulation of Multifunctional Calcium/Calmodulin Stimulated Protein Kinases by Molecular Targeting. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:649-679. [PMID: 31646529 DOI: 10.1007/978-3-030-12457-1_26] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Multifunctional calcium/calmodulin-stimulated protein kinases control a broad range of cellular functions in a multitude of cell types. This family of kinases contain several structural similarities and all are regulated by phosphorylation, which either activates, inhibits or modulates their kinase activity. As these protein kinases are widely or ubiquitously expressed, and yet regulate a broad range of different cellular functions, additional levels of regulation exist that control these cell-specific functions. Of particular importance for this specificity of function for multifunctional kinases is the expression of specific binding proteins that mediate molecular targeting. These molecular targeting mechanisms allow pools of kinase in different cells, or parts of a cell, to respond differently to activation and produce different functional outcomes.
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16
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Takabatake S, Ohtsuka S, Sugawara T, Hatano N, Kanayama N, Magari M, Sakagami H, Tokumitsu H. Regulation of Ca 2+/calmodulin-dependent protein kinase kinase β by cAMP signaling. Biochim Biophys Acta Gen Subj 2019; 1863:672-680. [PMID: 30660766 DOI: 10.1016/j.bbagen.2018.12.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2018] [Revised: 12/03/2018] [Accepted: 12/18/2018] [Indexed: 12/16/2022]
Abstract
BACKGROUND Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) is a pivotal activator of CaMKI, CaMKIV and 5'-AMP-activated protein kinase (AMPK), controlling Ca2+-dependent intracellular signaling including various neuronal, metabolic and pathophysiological responses. Recently, we demonstrated that CaMKKβ is feedback phosphorylated at Thr144 by the downstream AMPK, resulting in the conversion of CaMKKβ into Ca2+/CaM-dependent enzyme. However, the regulatory phosphorylation of CaMKKβ at Thr144 in intact cells and in vivo remains unclear. METHODS Anti-phosphoThr144 antibody was used to characterize the site-specific phosphorylation of CaMKKβ in immunoprecipitated samples from mouse cerebellum and in transfected mammalian cells that were treated with various agonists and protein kinase inhibitors. CaMKK activity assay and LC-MS/MS analysis were used for biochemical characterization of phosphorylated CaMKKβ. RESULTS Our data suggest that the phosphorylation of Thr144 in CaMKKβ is rapidly induced by cAMP/cAMP-dependent protein kinase (PKA) signaling in CaMKKβ-transfected HeLa cells, that is physiologically relevant in mouse cerebellum. We confirmed that the catalytic subunit of PKA was capable of directly phosphorylating CaMKKβ at Thr144 in vitro and in transfected cells. In addition, the basal phosphorylation of CaMKKβ at Thr144 in transfected HeLa cells was suppressed by AMPK inhibitor (compound C). PKA-catalyzed phosphorylation reduced the autonomous activity of CaMKKβ in vitro without significant effect on the Ca2+/CaM-dependent activity, resulting in the conversion of CaMKKβ into Ca2+/CaM-dependent enzyme. CONCLUSION cAMP/PKA signaling may confer Ca2+-dependency to the CaMKKβ-mediated signaling pathway through direct phosphorylation of Thr144 in intact cells. GENERAL SIGNIFICANCE Our results suggest a novel cross-talk between cAMP/PKA and Ca2+/CaM/CaMKKβ signaling through regulatory phosphorylation.
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Affiliation(s)
- Shota Takabatake
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Satomi Ohtsuka
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Takeyuki Sugawara
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Naoya Hatano
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Naoki Kanayama
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Masaki Magari
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan
| | - Hiroyuki Sakagami
- Department of Anatomy, Kitasato University School of Medicine, Sagamihara, Kanagawa 252-0374, Japan
| | - Hiroshi Tokumitsu
- Applied Cell Biology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University, Okayama 700-8530, Japan.
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17
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Brzozowski JS, Skelding KA. The Multi-Functional Calcium/Calmodulin Stimulated Protein Kinase (CaMK) Family: Emerging Targets for Anti-Cancer Therapeutic Intervention. Pharmaceuticals (Basel) 2019; 12:ph12010008. [PMID: 30621060 PMCID: PMC6469190 DOI: 10.3390/ph12010008] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2018] [Revised: 01/02/2019] [Accepted: 01/04/2019] [Indexed: 01/25/2023] Open
Abstract
The importance of Ca2+ signalling in key events of cancer cell function and tumour progression, such as proliferation, migration, invasion and survival, has recently begun to be appreciated. Many cellular Ca2+-stimulated signalling cascades utilise the intermediate, calmodulin (CaM). The Ca2+/CaM complex binds and activates a variety of enzymes, including members of the multifunctional Ca2+/calmodulin-stimulated protein kinase (CaMK) family. These enzymes control a broad range of cancer-related functions in a multitude of tumour types. Herein, we explore the cancer-related functions of these kinases and discuss their potential as targets for therapeutic intervention.
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Affiliation(s)
- Joshua S Brzozowski
- Priority Research Centre for Cancer Research, Innovation and Translation, School of Biomedical Sciences and Pharmacy, Hunter Medical Research Institute (HMRI) and University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Kathryn A Skelding
- Priority Research Centre for Cancer Research, Innovation and Translation, School of Biomedical Sciences and Pharmacy, Hunter Medical Research Institute (HMRI) and University of Newcastle, Callaghan, NSW 2308, Australia.
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18
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Sabbir MG. Loss of Ca 2+/Calmodulin Dependent Protein Kinase Kinase 2 Leads to Aberrant Transferrin Phosphorylation and Trafficking: A Potential Biomarker for Alzheimer's Disease. Front Mol Biosci 2018; 5:99. [PMID: 30525042 PMCID: PMC6256988 DOI: 10.3389/fmolb.2018.00099] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/25/2018] [Indexed: 01/19/2023] Open
Abstract
Ca2+/calmodulin-dependent protein kinase kinase 2 (CaMKK2) is a serine/threonine kinase that is activated following an increase in the intracellular Ca2+ concentration and activates multiple signaling cascades that control physiologically important neuronal processes. CaMKK2 has been implicated in schizophrenia, bipolar disease, neurodegeneration, and cancer. Using isoelectric focusing (IEF) and mass spectrometry-based proteomic analysis, it was found that knockdown (KD) of CaMKK2 in cultured adult primary dorsal root ganglion (DRG) neurons resulted in the reduction of transferrin (TF) phosphorylation at multiple functionally relevant residues which corresponded to loss of an acidic fraction (pH~3-4) of TF. In vitro studies using CRISPR/Cas9 based CaMKK2 knockout (KO) HEK293 and HepG2 cells lines validated previous findings and revealed that loss of CaMKK2 interfered with TF trafficking and turnover. TF is an iron transporter glycoprotein. Abnormal accumulation of iron and/or deregulated Ca2+ homeostasis leads to neurodegeneration in Alzheimer's disease (AD). Therefore, it was hypothesized that aberrant CaMKK2 in AD may lead to aberrant phosphorylated transferrin (P-TF: pH~3-4 fraction) which may serve as a hallmark biomarker for AD. A significant reduction of P-TF in the brain and serum of CaMKK2 KO mice and a triple-transgenic mouse model of AD (3xTg-AD) supported this hypothesis. In addition, analysis of early (< 65 years) and late-stage (>65 years) postmortem human AD cerebrospinal fluid (CSF) and serum samples revealed that aberrant P-TF (pH~3-4 fraction) profile was associated with both early and late-stage AD compared to age-matched controls. This indicates P-TF (pH~3-4 fraction) profile may be useful as a minimally invasive biomarker for AD. In addition, this study provides a link between aberrant CaMKK2 with TF trafficking and turnover which provides a novel insight into the neurodegeneration process.
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Affiliation(s)
- Mohammad Golam Sabbir
- Division of Neurodegenerative Disorders, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB, Canada
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19
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Gerner L, Munack S, Temmerman K, Lawrence-Dörner AM, Besir H, Wilmanns M, Jensen JK, Thiede B, Mills IG, Morth JP. Using the fluorescent properties of STO-609 as a tool to assist structure-function analyses of recombinant CaMKK2. Biochem Biophys Res Commun 2016; 476:102-7. [PMID: 27178209 DOI: 10.1016/j.bbrc.2016.05.045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/09/2016] [Indexed: 01/20/2023]
Abstract
Calcium/calmodulin-dependent kinase kinase 2 (CaMKK2) has been implicated in the regulation of metabolic activity in cancer and immune cells, and affects whole-body metabolism by regulating ghrelin-signalling in the hypothalamus. This has led to efforts to develop specific CaMKK2 inhibitors, and STO-609 is the standardly used CaMKK2 inhibitor to date. We have developed a novel fluorescence-based assay by exploiting the intrinsic fluorescence properties of STO-609. Here, we report an in vitro binding constant of KD ∼17 nM between STO-609 and purified CaMKK2 or CaMKK2:Calmodulin complex. Whereas high concentrations of ATP were able to displace STO-609 from the kinase, GTP was unable to achieve this confirming the specificity of this association. Recent structural studies on the kinase domain of CaMKK2 had implicated a number of amino acids involved in the binding of STO-609. Our fluorescent assay enabled us to confirm that Phe(267) is critically important for this association since mutation of this residue to a glycine abolished the binding of STO-609. An ATP replacement assay, as well as the mutation of the 'gatekeeper' amino acid Phe(267)Gly, confirmed the specificity of the assay and once more confirmed the strong binding of STO-609 to the kinase. In further characterising the purified kinase and kinase-calmodulin complex we identified a number of phosphorylation sites some of which corroborated previously reported CaMKK2 phosphorylation and some of which, particularly in the activation segment, were novel phosphorylation events. In conclusion, the intrinsic fluorescent properties of STO-609 provide a great opportunity to utilise this drug to label the ATP-binding pocket and probe the impact of mutations and other regulatory modifications and interactions on the pocket. It is however clear that the number of phosphorylation sites on CaMKK2 will pose a challenge in studying the impact of phosphorylation on the pocket unless the field can develop approaches to control the spectrum of modifications that occur during recombinant protein expression in Escherichia coli.
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Affiliation(s)
- Lisa Gerner
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Forskningsparken, University of Oslo, Oslo University Hospitals, 0349 Oslo, Norway
| | - Steffi Munack
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Forskningsparken, University of Oslo, Oslo University Hospitals, 0349 Oslo, Norway
| | - Koen Temmerman
- European Molecular Biology Laboratory Hamburg, Notkestrasse 85, 22603 Hamburg, Germany; European Molecular Biology Laboratory Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | | | - Hüseyin Besir
- European Molecular Biology Laboratory Heidelberg, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Matthias Wilmanns
- European Molecular Biology Laboratory Hamburg, Notkestrasse 85, 22603 Hamburg, Germany
| | - Jan Kristian Jensen
- Department of Molecular Biology and Genetics, Aarhus University, 8000 Aarhus, Denmark
| | - Bernd Thiede
- Department of Biosciences, University of Oslo, Norway
| | - Ian G Mills
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Forskningsparken, University of Oslo, Oslo University Hospitals, 0349 Oslo, Norway.
| | - Jens Preben Morth
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, Forskningsparken, University of Oslo, Oslo University Hospitals, 0349 Oslo, Norway.
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20
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Yu P, Chen X, Zhao W, Zhang Z, Zhang Q, Han B, Zhai J, Chen M, Du B, Deng X, Ji F, Wang C, Xiang YT, Li D, Wu H, Li J, Dong Q, Chen C. Effect of rs1063843 in the CAMKK2 gene on the dorsolateral prefrontal cortex. Hum Brain Mapp 2016; 37:2398-406. [PMID: 27004598 DOI: 10.1002/hbm.23181] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 02/28/2016] [Accepted: 03/01/2016] [Indexed: 11/07/2022] Open
Abstract
Recently, a single nucleotide polymorphism (SNP) in the CAMKK2 gene (rs1063843) was found to be associated with lower expression of the gene in the dorsolateral prefrontal cortex (DLPFC) and with schizophrenia (SCZ) and deficits in working memory and executive function. However, the brain mechanism underlying this association is poorly understood. A functional magnetic resonance imaging (fMRI) study (N = 84 healthy volunteers) involving multiple cognitive tasks, including a Stroop task (to measure attentional executive control), an N-back task (to measure working memory), and a delay discounting task (to measure decision making) to identify the brain regions affected by rs1063843 was performed. Across all three tasks, it was found that carriers of the risk allele consistently exhibited increased activation of the left DLPFC. In addition, the risk allele carriers also exhibited increased activation of the right DLPFC and the left cerebellum during the Stroop task and of the left caudate nucleus during the N-back task. These findings helped to elucidate the role of CAMKK2 in cognitive functions and in the etiology of SCZ. Hum Brain Mapp 37:2398-2406, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Ping Yu
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Xiongying Chen
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Wan Zhao
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Zhifang Zhang
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Qiumei Zhang
- School of Mental Health, Jining Medical University, 45# Jianshe South Road, Jining, Shandong Province, 272013, People's Republic of China
| | - Bingqian Han
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Jinguo Zhai
- School of Mental Health, Jining Medical University, 45# Jianshe South Road, Jining, Shandong Province, 272013, People's Republic of China
| | - Min Chen
- School of Mental Health, Jining Medical University, 45# Jianshe South Road, Jining, Shandong Province, 272013, People's Republic of China
| | - Boqi Du
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Xiaoxiang Deng
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Feng Ji
- School of Mental Health, Jining Medical University, 45# Jianshe South Road, Jining, Shandong Province, 272013, People's Republic of China
| | | | - Yu-Tao Xiang
- Beijing Anding Hospital, Beijing, 100088, China.,Faculty of Health Sciences, University of Macau, Taipa, Macau
| | - Dawei Li
- Center for Cognitive Neuroscience, Duke University, Durham, North Carolina, 27701
| | - Hongjie Wu
- Shengli Hospital of Shengli Petroleum Administration Bureau, Dongying, Shandong Province, 257022, People's Republic of China
| | - Jun Li
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Qi Dong
- State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China.,Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China
| | - Chuansheng Chen
- Department of Psychology and Social Behavior, University of California, Irvine, California, 92697
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Tessier SN, Storey KB. To be or not to be: the regulation of mRNA fate as a survival strategy during mammalian hibernation. Cell Stress Chaperones 2014; 19:763-76. [PMID: 24789358 PMCID: PMC4389848 DOI: 10.1007/s12192-014-0512-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 04/13/2014] [Indexed: 12/20/2022] Open
Abstract
Mammalian hibernators undergo profound behavioral, physiological, and biochemical changes in order to cope with hypothermia, ischemia-reperfusion, and finite fuel reserves over days or weeks of continuous torpor. Against a backdrop of global reductions in energy-expensive processes such as transcription and translation, a subset of genes/proteins are strategically upregulated in order to meet challenges associated with hibernation. Consequently, hibernation involves substantial transcriptional and posttranscriptional regulatory mechanisms and provides a phenomenon with which to understand how a set of common genes/proteins can be differentially regulated in order to enhance stress tolerance beyond that which is possible for nonhibernators. The present review focuses on the involvement of messenger RNA (mRNA) interacting factors that play a role in the regulation of gene/protein expression programs that define the hibernating phenotype. These include proteins involved in mRNA processing (i.e., capping, splicing, and polyadenylation) and the possible role of alternative splicing as a means of enhancing protein diversity. Since the total pool of mRNA remains constant throughout torpor, mechanisms which enhance mRNA stability are discussed in the context of RNA binding proteins and mRNA decay pathways. Furthermore, mechanisms which control the global reduction of cap-dependent translation and the involvement of internal ribosome entry sites in mRNAs encoding stress response proteins are also discussed. Finally, the concept of regulating each of these factors in discrete subcellular compartments for enhanced efficiency is addressed. The analysis draws on recent research from several well-studied mammalian hibernators including ground squirrels, bats, and bears.
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Affiliation(s)
- Shannon N. Tessier
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6 Canada
| | - Kenneth B. Storey
- Institute of Biochemistry & Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON K1S 5B6 Canada
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22
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Racioppi L, Means AR. Calcium/calmodulin-dependent protein kinase kinase 2: roles in signaling and pathophysiology. J Biol Chem 2012; 287:31658-65. [PMID: 22778263 DOI: 10.1074/jbc.r112.356485] [Citation(s) in RCA: 204] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Many cellular Ca(2+)-dependent signaling cascades utilize calmodulin (CaM) as the intracellular Ca(2+) receptor. Ca(2+)/CaM binds and activates a plethora of enzymes, including CaM kinases (CaMKs). CaMKK2 is one of the most versatile of the CaMKs and will phosphorylate and activate CaMKI, CaMKIV, and AMP-activated protein kinase. Cell expression of CaMKK2 is limited, yet CaMKK2 is involved in regulating many important physiological and pathophysiological processes, including energy balance, adiposity, glucose homeostasis, hematopoiesis, inflammation, and cancer. Here, we explore known functions of CaMKK2 and discuss its potential as a target for therapeutic intervention.
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Affiliation(s)
- Luigi Racioppi
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Duke University, Durham, North Carolina 27710, USA.
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Skelding KA, Rostas JAP. The role of molecular regulation and targeting in regulating calcium/calmodulin stimulated protein kinases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 740:703-30. [PMID: 22453966 DOI: 10.1007/978-94-007-2888-2_31] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Calcium/calmodulin-stimulated protein kinases can be classified as one of two types - restricted or multifunctional. This family of kinases contains several structural similarities: all possess a calmodulin binding motif and an autoinhibitory region. In addition, all of the calcium/calmodulin-stimulated protein kinases examined in this chapter are regulated by phosphorylation, which either activates or inhibits their kinase activity. However, as the multifunctional calcium/calmodulin-stimulated protein kinases are ubiquitously expressed, yet regulate a broad range of cellular functions, additional levels of regulation that control these cell-specific functions must exist. These additional layers of control include gene expression, signaling pathways, and expression of binding proteins and molecular targeting. All of the multifunctional calcium/calmodulin-stimulated protein kinases examined in this chapter appear to be regulated by these additional layers of control, however, this does not appear to be the case for the restricted kinases.
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Affiliation(s)
- Kathryn A Skelding
- School of Biomedical Sciences and Pharmacy and Hunter Medical Research Institute, Faculty of Health, The University of Newcastle, University Drive, Callaghan, NSW 2308, Australia
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Cao W, Sohail M, Liu G, Koumbadinga GA, Lobo VG, Xie J. Differential effects of PKA-controlled CaMKK2 variants on neuronal differentiation. RNA Biol 2011; 8:1061-72. [PMID: 21957496 DOI: 10.4161/rna.8.6.16691] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Regulation between protein kinases is critical for the establishment of signaling pathways/networks to 'orchestrate' cellular processes. Besides posttranslational phosphorylation, alternative pre-mRNA splicing is another way to control kinase properties, but splicing regulation between two kinases and the effect of resulting variants on cells has barely been explored. Here we examined the effect of the protein kinase A (PKA) pathway on the alternative splicing and variant properties of the Ca²⁺/calmodulin-dependent protein kinase kinase 2 (CaMKK2) gene in B35 neuroblastoma cells. Inclusion of the exon 16 of CaMKK2 was significantly reduced by H89, a PKA selective inhibitor. Consistently, overexpressed PKA strongly promoted the exon inclusion in a CaMKK2 sequence-dependent way in splicing reporter assays. In vitro, purified CaMKKβ1 variant proteins were found to be kinase-active. In cells, they were differentially phosphorylated by PKA. In RNA interference assays, CaMKKβ1 was found to be essential for forskolin-induced neurite growth. Interestingly, overexpression of the variant without exon 16 (-E16) promoted neurite elongation while the other one (+E16) promoted neurite branching; in contrast, reduction of the latter one enhanced neurite elongation. Moreover, the variants are differentially expressed and the exon 16-containing transcripts highly enriched in the brain, particularly the cerebellum and hippocampus. Thus, PKA regulates the alternative splicing of CaMKK2 to produce variants that differentially modulate neuronal differentiation. Taken together with the many distinct variants of kinases, alternative splicing regulation likely adds another layer of modulation between protein kinases in cellular signaling networks.
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Affiliation(s)
- Wenguang Cao
- Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada
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25
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Tokumitsu H, Hatano N, Fujimoto T, Yurimoto S, Kobayashi R. Generation of Autonomous Activity of Ca2+/Calmodulin-Dependent Protein Kinase Kinase β by Autophosphorylation. Biochemistry 2011; 50:8193-201. [DOI: 10.1021/bi201005g] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hiroshi Tokumitsu
- Department of Signal Transduction
Sciences, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Naoya Hatano
- The Integrated Center for Mass
Spectrometry, Graduate School of Medicine, Kobe University, Hyogo 650-0017, Japan
| | - Tomohito Fujimoto
- Department of Signal Transduction
Sciences, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Saki Yurimoto
- Department of Signal Transduction
Sciences, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Ryoji Kobayashi
- Department of Signal Transduction
Sciences, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan
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26
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Hsu LS, Liang CJ, Tseng CY, Yeh CW, Tsai JN. Zebrafish cyclin-dependent protein kinase-like 1 (zcdkl1): identification and functional characterization. Int J Mol Sci 2011; 12:3606-17. [PMID: 21747697 PMCID: PMC3131581 DOI: 10.3390/ijms12063606] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2011] [Revised: 05/19/2011] [Accepted: 05/22/2011] [Indexed: 11/16/2022] Open
Abstract
The cyclin-dependent protein kinase family regulates a wide range of cellular functions such as cell cycle progression, differentiation, and apoptosis. In this study, we identified a zebrafish cyclin-dependent protein kinase-like 1 protein called zebrafish cdkl1 (zcdkl1), which shared a high degree of homology and conserved synteny with mammalian orthologs. zcdkl1 exhibited abilities for phosphorylation of myelin basic protein and histone H1. RT-PCR analysis revealed that zcdkl1 was expressed starting from fertilization and continuing thereafter. In adult tissues, zcdkl1 was predominantly detected in brain, ovary, and testis, and was expressed at low levels in other tissues. At 50% epiboly stage, zcdkl1 was widely expressed. At 12 to 48 h post-fertilization, zcdkl1 was predominantly expressed in the hypochord, the medial and lateral floor plate, and the pronephric duct. Interference of zcdkl1 expression resulted in abnormalities, such as brain and eye malformation, pericardial edema, and body axis curvature. Disruption of zcdkl1 reduced neurogenin-1 in the brain and sonic hedgehog expression in the floor plate region. These deformities were apparently rescued by co-injection of zcdkl1 mRNA. Findings of this study indicate that zcdkl1 plays an essential role in zebrafish development.
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Affiliation(s)
- Li-Sung Hsu
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan; E-Mails: (C.-J.L.); (C.-Y.T.); (C.-W.Y.)
- Clinical Laboratory, Chung Shan Medical University Hospital, Taichung 402, Taiwan
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +886-4-24730022 ext. 11682; Fax: +886-4-23248195
| | - Cyong-Jhih Liang
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan; E-Mails: (C.-J.L.); (C.-Y.T.); (C.-W.Y.)
| | - Chen-Yuan Tseng
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan; E-Mails: (C.-J.L.); (C.-Y.T.); (C.-W.Y.)
| | - Chi-Wei Yeh
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan; E-Mails: (C.-J.L.); (C.-Y.T.); (C.-W.Y.)
| | - Jen-Ning Tsai
- School of Medical Laboratory and Biotechnology, Chung Shan Medical University, Taichung 402, Taiwan; E-Mail:
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27
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Hsu LS, Tseng CY. Zebrafish calcium/calmodulin-dependent protein kinase II (cam-kii) inhibitors: expression patterns and their roles in zebrafish brain development. Dev Dyn 2011; 239:3098-105. [PMID: 20925123 DOI: 10.1002/dvdy.22433] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Calcium/calmodulin-dependent protein kinase II (CaM-KII) plays a critical role in neuronal functions. In this report, we demonstrate the expression patterns, functional analysis, and development role of the two zebrafish CaM-KII inhibitors, cam-kiin1 and cam-kiin2. Both of these genes were detected in the 5-somite stage and are persistently expressed thereafter. The RNA transcripts of cam-kiin1 were prominently expressed in the forebrain and hindbrain regions, especially in the telencephalon, while cam-kiin2 was detected in the anterior brain region and neurons of the hindbrain. Through GST-pull down, co-immunoprecipitation, and kinase assay, cam-kii inhibitors can bind to and reduce cam-kiiα activity. However, no overt alternation of brain marker such as ngn1, otx2, and pax2.1 was observed in morphants received each one or combined MO. Our results suggest that the two cam-kii inhibitors exhibited distinct expression pattern and may play a minor role in zebrafish brain development.
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Affiliation(s)
- Li-Sung Hsu
- Institute of Biochemistry and Biotechnology, Chung Shan Medical University, Taichung, Taiwan.
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28
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Frigo DE, Howe MK, Wittmann BM, Brunner AM, Cushman I, Wang Q, Brown M, Means AR, McDonnell DP. CaM kinase kinase beta-mediated activation of the growth regulatory kinase AMPK is required for androgen-dependent migration of prostate cancer cells. Cancer Res 2010; 71:528-37. [PMID: 21098087 DOI: 10.1158/0008-5472.can-10-2581] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
While patients with advanced prostate cancer initially respond favorably to androgen ablation therapy, most experience a relapse of the disease within 1-2 years. Although hormone-refractory disease is unresponsive to androgen-deprivation, androgen receptor (AR)-regulated signaling pathways remain active and are necessary for cancer progression. Thus, both AR itself and the processes downstream of the receptor remain viable targets for therapeutic intervention. Microarray analysis of multiple clinical cohorts showed that the serine/threonine kinase Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) is both highly expressed in the prostate and further elevated in prostate cancers. Using cellular models of prostate cancer, we have determined that androgens (a) directly increase the expression of a CaMKKβ splice variant and (b) increase functional CaMKKβ protein levels as determined by the phosphorylation of both CaMKI and AMP-activated protein kinase (AMPK), two of CaMKKβ's primary substrates. Importantly, inhibition of the CaMKKβ-AMPK, but not CaMKI, signaling axis in prostate cancer cells by pharmacological inhibitors or siRNA-mediated knockdown blocks androgen-mediated migration and invasion. Conversely, overexpression of CaMKKβ alone leads to both increased AMPK phosphorylation and cell migration. Given the key roles of CaMKKβ and AMPK in the biology of prostate cancer cells, we propose that these enzymes are potential therapeutic targets in prostate cancer.
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Affiliation(s)
- Daniel E Frigo
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA
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29
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Lai RH, Wang MJ, Yang SH, Chen JY. Genomic organization and functional characterization of the promoter for the human suppressor of cytokine signaling 6 gene. Gene 2009; 448:64-73. [PMID: 19716864 DOI: 10.1016/j.gene.2009.07.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Revised: 07/02/2009] [Accepted: 07/12/2009] [Indexed: 11/18/2022]
Abstract
In this study, we report the expression and genomic structure of the gene encoding human suppressor of cytokine signaling 6 (SOCS6), and the characterization of the functional promoter region. The human SOCS6 gene, spanning 40 kb on chromosome 18q22.2, is composed of two exons separated by an intron of 35 kb. Two transcripts are ubiquitously expressed, and both encode the full-length open reading frame of SOCS6. A primer extension assay revealed that the major transcription initiation site is located 469 bp upstream the ATG codon. Luciferase promoter analysis demonstrated that the 5'-flanking region is able to drive transcription, and the CpG-rich sequences near the transcription initiation site are important for the TATA-less SOCS6 promoter activity. Analogous to SOCS1 and SOCS3, which are down-regulated in several human cancers, SOCS6 is expressed at lower levels in carcinomas of stomach and colon. We demonstrated that hypermethylation of the SOCS6 promoter is one of the mechanisms for the epigenetic regulation of SOCS6 expression. Firstly, in vitro methylation of the reporter promoter plasmid significantly suppressed the promoter activity. Secondly, SOCS6 expression in vivo was enhanced by treating cells with a methyltransferase inhibitor. The SOCS6 gene from various species shares significant homology in amino acid sequences, transcription factor binding motifs in promoter regions and the two-exon genomic structure, suggesting that the SOCS6 gene is highly conserved.
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Affiliation(s)
- Rai-Hua Lai
- Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan, ROC
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30
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Li H, Liu G, Yu J, Cao W, Lobo VG, Xie J. In vivo selection of kinase-responsive RNA elements controlling alternative splicing. J Biol Chem 2009; 284:16191-16201. [PMID: 19386606 DOI: 10.1074/jbc.m900393200] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Alternative pre-mRNA splicing is often controlled by cell signals, for example, those activating the cAMP-dependent protein kinase (PKA) or the Ca2+/calmodulin-dependent protein kinase IV (CaMKIV). We have shown that CaMKIV regulates alternative splicing through short CA repeats and hnRNP L. Here we use a splicing reporter that shows PKA/CaMKIV promotion of exon inclusion to select from exons containing random 13-nt sequences for RNA elements responsive to the kinases in cultured cells. This selection not only identified both PKA- and CaMKIV-responsive elements that are similar to the CaMKIV-responsive RNA element 1 (CaRRE1) or CA repeats, but also A-rich elements not previously known to respond to these kinases. Consistently, hnRNP L is identified as a factor binding the CA-rich elements. Analyses of the motifs in the highly responsive elements indicate that they are indeed critical for the kinase effect and are enriched in alternative exons. Interestingly, a CAAAAAA motif is sufficient for the PKA/CaMKIV-regulated splicing of the exon 16 of the CaMK kinase beta1 (CaMKK2) transcripts, implying a role of this motif in signaling cross-talk or feedback regulation between these kinases through alternative splicing. Therefore, these experiments identified a group of RNA elements responsive to PKA and CaMKIV from in vivo selection. This also provides an approach for selecting RNA elements similarly responsive to other cell signals controlling alternative splicing.
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Affiliation(s)
- Hongzhao Li
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Guodong Liu
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Jiankun Yu
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Wenguang Cao
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Vincent G Lobo
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada
| | - Jiuyong Xie
- From the Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba R3E 0J9, Canada.
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31
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Takai N, Ueda T, Nasu K, Yamashita S, Toyofuku M, Narahara H. Targeting calcium/calmodulin-dependence kinase I and II as a potential anti-proliferation remedy for endometrial carcinomas. Cancer Lett 2009; 277:235-43. [PMID: 19168280 DOI: 10.1016/j.canlet.2008.12.018] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Revised: 12/09/2008] [Accepted: 12/09/2008] [Indexed: 11/17/2022]
Abstract
Calcium/calmodulin-dependent kinase (CaMK) I and II expression in endometrial cancer cells correlates with the malignant potential of this tumor, and CaMKI and II are potential therapeutic targets in endometrial cancer. CaMKI and II expression was significantly associated with PCNA-labeling index, clinical stage, histological grade, the presence of invasion to greater than one-half the myometrium, and clinical outcome. All endometrial cancer cell lines examined were sensitive to the growth-inhibitory effect of KN-93, a membrane-permeant CaMKs-selective inhibitor that is competitive with calmodulin. KN-93 induced the G0/G1 arrest and apoptosis, rising hopes that KN-93 may become a useful treatment for endometrial cancers.
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Affiliation(s)
- Noriyuki Takai
- Department of Obstetrics and Gynecology, Oita University Faculty of Medicine, 1-1 Idaigaioka, Hasama-machi, Yufu-shi, Oita, Japan.
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32
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Colomer J, Means AR. Physiological roles of the Ca2+/CaM-dependent protein kinase cascade in health and disease. Subcell Biochem 2008; 45:169-214. [PMID: 18193638 DOI: 10.1007/978-1-4020-6191-2_7] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Numerous hormones, growth factors and physiological processes cause a rise in cytosolic Ca2+, which is translated into meaningful cellular responses by interacting with a large number of Ca2(+)-binding proteins. The Ca2(+)-binding protein that is most pervasive in mediating these responses is calmodulin (CaM), which acts as a primary receptor for Ca2+ in all eukaryotic cells. In turn, Ca2+/CaM functions as an allosteric activator of a host of enzymatic proteins including a considerable number of protein kinases. The topic of this review is to discuss the physiological roles of a sub-set of these protein kinases which can function in cells as a Ca2+/CaM-dependent kinase signaling cascade. The cascade was originally believed to consist of a CaM kinase kinase that phosphorylates and activates one of two CaM kinases, CaMKI or CaMKIV. The unusual aspect of this cascade is that both the kinase kinase and the kinase require the binding of Ca2+/CaM for activation. More recently, one of the CaM kinase kinases has been found to activate another important enzyme, the AMP-dependent protein kinase so the concept of the CaM kinase cascade must be expanded. A CaM kinase cascade is important for many normal physiological processes that when misregulated can lead to a variety of disease states. These processes include: cell proliferation and apoptosis that may conspire in the genesis of cancer; neuronal growth and function related to brain development, synaptic plasticity as well as memory formation and maintenance; proper function of the immune system including the inflammatory response, activation of T lymphocytes and hematopoietic stem cell maintenance; and the central control of energy balance that, when altered, can lead to obesity and diabetes. Although the study of the CaM-dependent kinase cascades is still in its infancy continued analysis of the pathways regulated by these Ca2(+)-initiated signaling cascades holds considerable promise for the future of disease-related research.
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Affiliation(s)
- J Colomer
- Department of Pharmacology and Cancer Biology, Duke University Medical Center USA
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33
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Yuan L, Chen J, Lin B, Liang B, Zhang S, Wu D. Up-regulation of a non-kinase activity isoform of Ca2+/calmodulin-dependent protein kinase kinase beta1 (CaMKKβ1) in hibernating bat brain. Comp Biochem Physiol B Biochem Mol Biol 2007; 146:438-44. [PMID: 17258919 DOI: 10.1016/j.cbpb.2006.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2006] [Revised: 12/04/2006] [Accepted: 12/05/2006] [Indexed: 11/17/2022]
Abstract
Hibernation is an adaptive strategy that is utilized by some animals to survive the harsh environments of low temperature and food scarce. Hibernators, however, can survive in frequent and dramatic fluctuation of body temperature and blood flow causing by periodic arousals during hibernation without brain insult, and this indicates that it must have some unique adaptive aspects of hibernation physiology. To find out the up-regulated genes of bat brain during hibernation and explore the brain function adaptive mechanism of bat, the suppression subtractive hybridization (SSH) library was constructed from the brain tissue of greater horseshoe bats. Dot blot screening was carried out and the up-regulated genes in hibernating state were obtained. Then RT-PCR and RQ-PCR were performed to test the expression patterns of selected cDNAs. Here we first show that the functional and non-functional isoforms of bat CaMKKbeta1 display distinct expression patterns between hibernating and active states. The up-regulation of non-functional form of CaMKKbeta1 may represent a new neuroprotective strategy adopted by bats or even other hibernators to avoid the CNS damage during hibernation. Our results showed that bat CaMKKbeta1 gene has four transcript isoforms and these transcript variants differ primarily in exons b and d, which are 129 bp and 43 bp respectively. Statistical analyses indicated that these isoforms display distinct expression patterns at different states, in which only isoform 3, the non-functional form, increased 300% at hibernating state. These results suggest that distinct expression patterns of transcript isoforms of a gene, which have different activity, may represent a new potential adaptive mechanism in hibernation, except for the simple up-regulation of selected genes/proteins and the reversible protein phosphorylation.
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Affiliation(s)
- Lihong Yuan
- Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China
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Rodriguez-Mora OG, LaHair MM, McCubrey JA, Franklin RA. Calcium/calmodulin-dependent kinase I and calcium/calmodulin-dependent kinase kinase participate in the control of cell cycle progression in MCF-7 human breast cancer cells. Cancer Res 2005; 65:5408-16. [PMID: 15958590 DOI: 10.1158/0008-5472.can-05-0271] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Calcium is universally required for cell growth and proliferation. Calmodulin is the main intracellular receptor for calcium. Although calcium and calmodulin are well known to be required for cell cycle regulation, the target pathways for their action remain poorly defined. Potential targets include the calcium/calmodulin-dependent kinases (CaM-K). The aim of this study was to determine the role of the CaM-Ks on cell proliferation and progress through the cell cycle in breast cancer cells. CaM-KI inhibition with either KN-93 or specific interfering RNA (siRNA) caused an arrest in the cell cycle in the human breast cancer cell line, MCF-7. This arrest occurred in the G(1) phase of the cell cycle. Supporting this finding, CaM-K inhibition using KN-93 also resulted in a reduction of cyclin D1 protein and pRb phosphorylation when cells were compared with control cultures. Furthermore, inhibition of the upstream activator of CaM-KI, CaM-KK, using siRNA also resulted in cell cycle arrest. In summary, CaM-KK and CaM-KI participate in the control of the G(0)-G(1) restriction check point of the cell cycle in human breast cancer cells. This arrest seems due to an inhibition in cyclin D1 synthesis and a reduction in pRb phosphorylation. To the best of our knowledge, this is the first time that CaM-KK has been reported to be involved in mammalian cell cycle regulation and that CaM-Ks are regulating breast cancer cell cycle.
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Affiliation(s)
- Oswaldo G Rodriguez-Mora
- Department of Microbiology and Immunology and the Leo Jenkins Cancer Center, Brody School of Medicine at East Carolina University, Greenville, North Carolina 27834, USA
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35
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Hurley RL, Anderson KA, Franzone JM, Kemp BE, Means AR, Witters LA. The Ca2+/calmodulin-dependent protein kinase kinases are AMP-activated protein kinase kinases. J Biol Chem 2005; 280:29060-6. [PMID: 15980064 DOI: 10.1074/jbc.m503824200] [Citation(s) in RCA: 795] [Impact Index Per Article: 41.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The AMP-activated protein kinase (AMPK) is an important regulator of cellular metabolism in response to metabolic stress and to other regulatory signals. AMPK activity is absolutely dependent upon phosphorylation of AMPKalphaThr-172 in its activation loop by one or more AMPK kinases (AMPKKs). The tumor suppressor kinase, LKB1, is a major AMPKK present in a variety of tissues and cells, but several lines of evidence point to the existence of other AMPKKs. We have employed three cell lines deficient in LKB1 to study AMPK regulation and phosphorylation, HeLa, A549, and murine embryo fibroblasts derived from LKB(-/-) mice. In HeLa and A549 cells, mannitol, 2-deoxyglucose, and ionomycin, but not 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR), treatment activates AMPK by alphaThr-172 phosphorylation. These responses, as well as the downstream effects of AMPK on the phosphorylation of acetyl-CoA carboxylase, are largely inhibited by the Ca(2+)/ calmodulin-dependent protein kinase kinase (CaMKK) inhibitor, STO-609. AMPKK activity in HeLa cell lysates measured in vitro is totally inhibited by STO-609 with an IC50 comparable with that of the known CaMKK isoforms, CaMKKalpha and CaMKKbeta. Furthermore, 2-deoxyglucose- and ionomycin-stimulated AMPK activity, alphaThr-172 phosphorylation, and acetyl-CoA carboxylase phosphorylation are substantially reduced in HeLa cells transfected with small interfering RNAs specific for CaMKKalpha and CaMKKbeta. Lastly, the activation of AMPK in response to ionomycin and 2-deoxyglucose is not impaired in LKB1(-/-) murine embryo fibroblasts. These data indicate that the CaMKKs function in intact cells as AMPKKs, predicting wider roles for these kinases in regulating AMPK activity in vivo.
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Affiliation(s)
- Rebecca L Hurley
- Departments of Medicine and Biochemistry, Dartmouth Medical School and the Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA
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36
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Hsieh HL, Yen MH, Jou MJ, Yang CM. Intracellular signalings underlying bradykinin-induced matrix metalloproteinase-9 expression in rat brain astrocyte-1. Cell Signal 2004; 16:1163-76. [PMID: 15240011 DOI: 10.1016/j.cellsig.2004.03.021] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2004] [Revised: 03/12/2004] [Accepted: 03/15/2004] [Indexed: 11/21/2022]
Abstract
Bradykinin (BK), an inflammatory mediator, has been shown to increase the expression of proteins such as matrix metalloproteinases (MMPs) on brain cells and contributes to the pathophysiology of inflammatory responses. However, the mechanisms regulating MMP-9 expression by BK in rat brain astrocytes-1 (RBA-1) remain unclear. Here we report that the mitogen-activated protein kinase (MAPK) and NF-kappaB pathways participate in the induction of MMP-9 expression induced by BK in RBA cells. Zymographic, Western blotting, and RT-PCR analyses showed that BK increased expression of MMP-9 mRNA and protein in a time- and concentration-dependent manner. BK-induced MMP-9 mRNA and protein expression was inhibited by MEK1/2 inhibitor PD98059, PI3-K inhibitor LY294002, and NF-kappaB inhibitor helenalin. In accordance with these findings, BK-induced phosphorylation of p42/p44 MAPK and Akt and activation of NF-kappaB was attenuated by prior treatment with PD98059, LY294002, and helenalin, respectively. The effects of BK on MMP-9 expression and p42/p44 MAPK and Akt phosphorylation were inhibited by B(2) receptor antagonist Hoe 140, indicating the involvement of B(2) receptors revealed by [(3)H]-BK binding assay. Furthermore, BK-stimulated translocation of NF-kappaB into the nucleus was revealed by Western blotting and immnofluorescence staining and blocked by Hoe140, PD98059, LY294002, and helenalin. Taken together, these results suggest that in RBA cells, activation of p42/p44 MAPK and Akt cascades mediated through NF-kappaB pathway are essential for BK-induced MMP-9 gene expression. This study may provide insights into the regulation of MMP-9 production in CNS, which may occur in vivo in pathological situations such as CNS inflammation and brain astrocytoma.
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Affiliation(s)
- Hsi-Lung Hsieh
- Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan, ROC
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37
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Loss of Ca2+/calmodulin kinase kinase beta affects the formation of some, but not all, types of hippocampus-dependent long-term memory. J Neurosci 2003. [PMID: 14586002 DOI: 10.1523/jneurosci.23-30-09752.2003] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Long-term memory (LTM) requires activation of the transcription factor cAMP-responsive element binding protein (CREB). Signaling by the Ca2+/calmodulin (CaM) kinase cascade has been implicated in CREB activation and memory consolidation processes in the hippocampus. The CaM kinase kinase beta isoforms belong to the CaM kinase cascade, and we have generated null mutant mice to investigate the role of these kinases in several forms of learning and memory. The null mutants were impaired in spatial training-induced CREB activation and spatial memory formation. Furthermore, the mutants lacked late, but not early, long-term potentiation at the hippocampal CA1 synapse, and they were impaired in LTM, but not short-term memory, for the social transmission of food preferences. We suggest that the CaM kinase kinasebeta isoforms are required for the formation of hippocampal LTM. Surprisingly, however, these kinases were not needed for contextual, trace fear, and passive avoidance LTM. Our results demonstrate that different signaling processes underlie the formation of these types of hippocampal LTM.
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Ishikawa Y, Tokumitsu H, Inuzuka H, Murata-Hori M, Hosoya H, Kobayashi R. Identification and characterization of novel components of a Ca2+/calmodulin-dependent protein kinase cascade in HeLa cells. FEBS Lett 2003; 550:57-63. [PMID: 12935886 DOI: 10.1016/s0014-5793(03)00817-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
In this report, we cloned a novel calmodulin-kinase (CaM-KIdelta) from HeLa cells and characterized its activation mechanism. CaM-KIdelta exhibits Ca(2+)/CaM-dependent activity that is enhanced (approximately 30-fold) in vitro by phosphorylation of its Thr180 by CaM-K kinase (CaM-KK)alpha, consistent with detection of CaM-KIdelta-activating activity in HeLa cells. We also identified a novel CaM-KKbeta isoform (CaM-KKbeta-3) in HeLa cells whose activity was highly Ca(2+)/CaM-independent. Transiently expressed CaM-KIdelta exhibited enhanced protein kinase activity in HeLa cells without ionomycin stimulation. This sustained activation of CaM-KIdelta was completely abolished by Thr180Ala mutation and inhibited by CaM-KK inhibitor, STO-609, indicating a functional CaM-KK/CaM-KIdelta cascade in HeLa cells.
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Affiliation(s)
- Yumi Ishikawa
- Department of Signal Transduction Sciences, Kagawa Medical University, 1750-1 Miki-cho, Kita-gun, Kagawa 761-0793, Japan
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Vinet J, Carra S, Blom JMC, Harvey M, Brunello N, Barden N, Tascedda F. Cloning of mouse Ca2+/calmodulin-dependent protein kinase kinase beta (CaMKKbeta) and characterization of CaMKKbeta and CaMKKalpha distribution in the adult mouse brain. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 2003; 111:216-21. [PMID: 12654522 DOI: 10.1016/s0169-328x(02)00698-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The Ca(2+)/calmodulin-dependent protein kinase kinases alpha and beta (CaMKKs alpha and beta) are novel members of the CaM kinase family. The CaMKKbeta was cloned from mouse brain. The deduced amino acid sequence shared 96.43% homology with the rat CaMKKbeta. Both the alpha and beta isoforms were widely distributed throughout the adult mouse brain. Additionally, all peripheral tissues examined displayed CaMKK alpha and beta expression.
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Affiliation(s)
- Jonathan Vinet
- Dipartimento di Scienze Farmaceutiche, Università degli Studi di Modena e Reggio Emilia, Via Campi 183, 41100 Modena, Italy
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