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Sritawan N, Sirichoat A, Aranarochana A, Pannangrong W, Wigmore P, Welbat JU. Protective effect of metformin on methotrexate induced reduction of rat hippocampal neural stem cells and neurogenesis. Biomed Pharmacother 2023; 162:114613. [PMID: 37001179 DOI: 10.1016/j.biopha.2023.114613] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 03/18/2023] [Accepted: 03/26/2023] [Indexed: 03/30/2023] Open
Abstract
Adult neurogenesis is a process in which the adult neural stem cells produce newborn neurons that are implicated in terms of learning and memory. Methotrexate (MTX) is a chemotherapeutic drug, which has a negative effect on memory and hippocampal neurogenesis in animal models. Metformin is an antidiabetic drug with strong antioxidant capacities. We found that metformin ameliorates MTX induced deteriorations of memory and hippocampal neurogenesis in adult rats. In this study, we focus to investigate neural stem cells, biomarkers of apoptosis, and the protein for synaptogenesis, which involves in the transcription factors of the hippocampus in rats that received metformin and MTX. Male Sprague-Dawley rats were composed of control, MTX, metformin, and MTX+metformin groups. MTX (75 mg/kg, i.v.) was given on days 7 and 14, whereas metformin (200 mg/kg, i.p.) was given for 14 days. Hippocampal neural stem cells in the subgranular zone (SGZ) were quantified using immunofluorescence staining of Sox2 and nestin. Protein expression including PSD95, Casepase-3, Bax, Bcl-2, CREB, and pCREB were determined using Western blotting. MTX-treated rats displayed decreases in Sox2 and nestin-positive cells in the SGZ. Increases in Caspase-3 and Bax levels and decreases in PSD95, Bcl-2, CREB, and pCREB protein expressions in the hippocampus were also detected. However, these negative impacts of MTX were ameliorated by co-treatment with metformin. These consequences postulate that metformin has a potential to increase neural stem cells, synaptic plasticity, decreased apoptotic activities, and transcription factors, resulting in upregulation of hippocampal neurogenesis in MTX-treated rats.
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Affiliation(s)
- Nataya Sritawan
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Neurogenesis Research Group, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
| | - Apiwat Sirichoat
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Neurogenesis Research Group, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
| | - Anusara Aranarochana
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Neurogenesis Research Group, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
| | - Wanassanan Pannangrong
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Neurogenesis Research Group, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
| | - Peter Wigmore
- School of Life Sciences, Medical School, Queen's Medical Centre, University of Nottingham, Nottingham NG7 2RD, UK.
| | - Jariya Umka Welbat
- Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand; Neurogenesis Research Group, Department of Anatomy, Faculty of Medicine, Khon Kaen University, Khon Kaen 40002, Thailand.
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Rojas DA, Urbina F, Solari A, Maldonado E. The Catalytic Subunit of Schizosaccharomyces pombe CK2 (Cka1) Negatively Regulates RNA Polymerase II Transcription through Phosphorylation of Positive Cofactor 4 (PC4). Int J Mol Sci 2022; 23:ijms23169499. [PMID: 36012759 PMCID: PMC9409219 DOI: 10.3390/ijms23169499] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 01/04/2023] Open
Abstract
Positive cofactor 4 (PC4) is a transcriptional coactivator that plays important roles in transcription and DNA replication. In mammals, PC4 is phosphorylated by CK2, and this event downregulates its RNA polymerase II (RNAPII) coactivator function. This work describes the effect of fission yeast PC4 phosphorylation on RNAPII transcription in a cell extract, which closely resembles the cellular context. We found that fission yeast PC4 is strongly phosphorylated by the catalytic subunit of CK2 (Cka1), while the regulatory subunit (Ckb1) downregulates the PC4 phosphorylation. The addition of Cka1 to an in vitro transcription assay can diminish the basal transcription from the Ad-MLP promoter; however, the addition of recombinant fission yeast PC4 or Ckb1 can stimulate the basal transcription in a cell extract. Fission yeast PC4 is phosphorylated in a domain which has consensus phosphorylation sites for CK2, and two serine residues were identified as critical for CK2 phosphorylation. Mutation of one of the serine residues in PC4 does not completely abolish the phosphorylation; however, when the two serine residues are mutated, CK2 is no longer able to phosphorylate PC4. The mutant which is not phosphorylated is able to stimulate transcription even though it is previously phosphorylated by Cka1, while the wild type and the point mutant are inactivated by Cka1 phosphorylation, and they cannot stimulate transcription by RNAPII in cell extracts. Those results demonstrate that CK2 can regulate the coactivator function of fission yeast PC4 and suggests that this event could be important in vivo as well.
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Affiliation(s)
- Diego A. Rojas
- Instituto de Ciencias Biomédicas (ICB), Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Santiago 8910132, Chile
- Correspondence: (D.A.R.); (E.M.)
| | - Fabiola Urbina
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago 8380492, Chile
| | - Aldo Solari
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago 8380492, Chile
| | - Edio Maldonado
- Programa de Biología Celular y Molecular, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago 8380492, Chile
- Correspondence: (D.A.R.); (E.M.)
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Molecular allocation of PC4s provides implications for deciphering thermal response in Zhikong scallop (Chlamys farreri). Gene 2022; 818:146216. [PMID: 35093447 DOI: 10.1016/j.gene.2022.146216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/04/2021] [Accepted: 01/13/2022] [Indexed: 12/15/2022]
Abstract
The increasing sea temperature caused by global warming has led to serious death of Zhikong scallop (Chlamys farreri) and improving its thermal tolerance has become an active research area in scallop aquaculture industry. Gene transcriptional coactivator p15 (PC4) plays pivotally multi-faced roles in most vertebrates and some invertebrates, but the systematic identification and characterization of PC4 genes have less been reported in scallops. In this study, 15 PC4 genes (CfPC4s) were identified in Zhikong scallop through whole-genome scanning, including two pairs of tandem duplicate genes located in the same scaffold (CF-19495.9 and CF-19495.10, CF-6819.1 and CF-6819.2). Protein structural and phylogenetic analyses were performed to verify identities and evolutionary relationships of these genes. Spatiotemporal expression patterns were determined at different development stages and in healthy adult tissues, as well as expression regulations in selected tissues (mantles, gills, hemocytes and hearts) after high temperatures challenge (27 °C) with different durations (3 h, 6 h, 12 h, 24 h, 3 d, 6 d, 15 d and 30 d). Spatiotemporal expressions of CfPC4s were ubiquitous but exhibited different patterns, suggesting the functional roles of CfPC4s in all stages of growth and development of the scallop. Expression regulations of CfPC4s and their functional related factors (TFIIA, TFIID, TFIIH and RNAPII) in pre-initiation complex (PIC) in various tissues displayed up- and/or down-regulated responses at different time points, showing time- and/or tissue-dependent expression patterns with function allocation upon different thermal durations. Collectively, this study demonstrated that gene allocation of CfPC4s provided implications for deciphering thermal response in Zhikong scallop and potentially helped in developing strategies for long-term healthy sustainable Zhikong scallop culture.
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Abdel-Hamid M, Yang P, Mostafa I, Osman A, Romeih E, Yang Y, Huang Z, Awad AA, Li L. Changes in Whey Proteome between Mediterranean and Murrah Buffalo Colostrum and Mature Milk Reflect Their Pharmaceutical and Medicinal Value. Molecules 2022; 27:1575. [PMID: 35268677 PMCID: PMC8912021 DOI: 10.3390/molecules27051575] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 01/27/2023] Open
Abstract
Milk represents an integrated meal for newborns; its whey protein is rich in many health beneficial components and proteins. The current study aimed to investigate the differences between colostrum and mature milk from Mediterranean and Murrah buffaloes using labeled proteomics and bioinformatics tools. In the current work, LC-MS/MS analysis led to identification of 780 proteins from which 638 were shared among three independent TMT experiments. The significantly changed proteins between the studied types were analyzed using gene ontology enrichment and KEGG pathways, and their interactions were generated using STRING database. Results indicated that immunological, muscular development and function, blood coagulation, heme related, neuronal, translation, metabolic process, and binding proteins were the main terms. Overall, colostrum showed higher levels of immunoglobulins, myosins, actin, neurofascin, syntaxins, thyroglobulins, and RNA-binding proteins, reflecting its importance in the development and activity of immunological, muscular, cardiac, neuronal, and thyroid systems, while lactoferrin and ferritin were increased in mature milk, highlighting its role in iron storage and hemoglobin formation.
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Affiliation(s)
- Mahmoud Abdel-Hamid
- Guangxi Buffalo Research Institute, Chinese Academy of Agricultural Sciences, Nanning 530001, China; (M.A.-H.); (P.Y.); (Z.H.)
- Dairy Science Department, Faculty of Agriculture, Cairo University, Giza 12613, Egypt; (E.R.); (A.A.A.)
| | - Pan Yang
- Guangxi Buffalo Research Institute, Chinese Academy of Agricultural Sciences, Nanning 530001, China; (M.A.-H.); (P.Y.); (Z.H.)
| | - Islam Mostafa
- Department of Pharmacognosy, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt;
| | - Ali Osman
- Biochemistry Department, Faculty of Agriculture, Zagazig University, Zagazig 44511, Egypt;
| | - Ehab Romeih
- Dairy Science Department, Faculty of Agriculture, Cairo University, Giza 12613, Egypt; (E.R.); (A.A.A.)
| | - Yongxin Yang
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao 266109, China;
| | - Zizhen Huang
- Guangxi Buffalo Research Institute, Chinese Academy of Agricultural Sciences, Nanning 530001, China; (M.A.-H.); (P.Y.); (Z.H.)
| | - Awad A. Awad
- Dairy Science Department, Faculty of Agriculture, Cairo University, Giza 12613, Egypt; (E.R.); (A.A.A.)
| | - Ling Li
- Guangxi Buffalo Research Institute, Chinese Academy of Agricultural Sciences, Nanning 530001, China; (M.A.-H.); (P.Y.); (Z.H.)
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Chen L, Liao F, Wu J, Wang Z, Jiang Z, Zhang C, Luo P, Ma L, Gong Q, Wang Y, Wang Q, Luo M, Yang Z, Han S, Shi C. Acceleration of ageing via disturbing mTOR-regulated proteostasis by a new ageing-associated gene PC4. Aging Cell 2021; 20:e13370. [PMID: 33957702 PMCID: PMC8208792 DOI: 10.1111/acel.13370] [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: 11/27/2020] [Revised: 02/21/2021] [Accepted: 03/31/2021] [Indexed: 01/08/2023] Open
Abstract
Research on ageing‐associated genes is important for investigating ageing and anti‐ageing strategies. Here, we firstly reported that the human positive cofactor 4 (PC4), a multifunctional and highly conserved nucleoprotein, is accumulated and activated during ageing and causes global accelerated ageing process by disrupting proteostasis. Mechanistically, PC4 interacts with Sin3‐HDAC complex and inhibits its deacetylated activity, leads to hyper‐acetylation of the histones at the promoters of mTOR‐related genes and causes mTOR signalling activation. Accordingly, mTOR activation causes excessive protein synthesis, resulting in impaired proteostasis and accelerated senescence. These results reveal a new biological function of PC4 in vivo, recognizes PC4 as a new ageing‐associated gene and provides a genetically engineered mouse model to simulate natural ageing. More importantly, our findings also indicate that PC4 is involved in histone acetylation and serves as a potential target to improve proteostasis and delay ageing.
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Affiliation(s)
- Long Chen
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Fengying Liao
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Jie Wu
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Ziwen Wang
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
- Department of Cardiology Geriatric Cardiovascular Disease Research and Treatment Center 252 Hospital of PLA (82nd Group Army Hospital of PLA) Baoding China
| | - Zhongyong Jiang
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Chi Zhang
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Peng Luo
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Le Ma
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Qiang Gong
- Department of Hematology Southwest Hospital Third Military Medical University Chongqing China
| | - Yang Wang
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Qing Wang
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Min Luo
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
| | - Zeyu Yang
- Breast and Thyroid Surgical Department Chongqing General Hospital University of Chinese Academy of Sciences Chongqing China
| | - Shiqian Han
- Institute of Tropical Medicine Third Military Medical University Chongqing China
| | - Chunmeng Shi
- Institute of Rocket Force Medicine State Key Laboratory of Trauma, Burns and Combined Injury Third Military Medical University Chongqing China
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Ochiai K, Yamaoka M, Swaminathan A, Shima H, Hiura H, Matsumoto M, Kurotaki D, Nakabayashi J, Funayama R, Nakayama K, Arima T, Ikawa T, Tamura T, Sciammas R, Bouvet P, Kundu TK, Igarashi K. Chromatin Protein PC4 Orchestrates B Cell Differentiation by Collaborating with IKAROS and IRF4. Cell Rep 2020; 33:108517. [PMID: 33357426 DOI: 10.1016/j.celrep.2020.108517] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 10/10/2020] [Accepted: 11/22/2020] [Indexed: 12/24/2022] Open
Abstract
The chromatin protein positive coactivator 4 (PC4) has multiple functions, including chromatin compaction. However, its role in immune cells is largely unknown. We show that PC4 orchestrates chromatin structure and gene expression in mature B cells. B-cell-specific PC4-deficient mice show impaired production of antibody upon antigen stimulation. The PC4 complex purified from B cells contains the transcription factors (TFs) IKAROS and IRF4. IKAROS protein is reduced in PC4-deficient mature B cells, resulting in de-repression of their target genes in part by diminished interactions with gene-silencing components. Upon activation, the amount of IRF4 protein is not increased in PC4-deficient B cells, resulting in reduction of plasma cells. Importantly, IRF4 reciprocally induces PC4 expression via a super-enhancer. PC4 knockdown in human B cell lymphoma and myeloma cells reduces IKAROS protein as an anticancer drug, lenalidomide. Our findings establish PC4 as a chromatin regulator of B cells and a possible therapeutic target adjoining IKAROS in B cell malignancies.
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Affiliation(s)
- Kyoko Ochiai
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan.
| | - Mari Yamaoka
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Amrutha Swaminathan
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India
| | - Hiroki Shima
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Hitoshi Hiura
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Mitsuyo Matsumoto
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan; Center for Regulatory Epigenome and Diseases, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Daisuke Kurotaki
- Department of Immunology, Yokohama City University Graduate School of Medicine, Fukuura 3-9, Yokohama 236-0004, Japan
| | - Jun Nakabayashi
- Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Yokohama 236-0004, Japan
| | - Ryo Funayama
- Center for Regulatory Epigenome and Diseases, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan; Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Keiko Nakayama
- Center for Regulatory Epigenome and Diseases, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan; Division of Cell Proliferation, United Centers for Advanced Research and Translational Medicine, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Takahiro Arima
- Department of Informative Genetics, Environment and Genome Research Center, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan
| | - Tomokatsu Ikawa
- Division of Immunobiology, Tokyo University of Science, Yamazaki 2669, Noda 278-0022, Japan
| | - Tomohiko Tamura
- Department of Immunology, Yokohama City University Graduate School of Medicine, Fukuura 3-9, Yokohama 236-0004, Japan; Advanced Medical Research Center, Yokohama City University, Fukuura 3-9, Yokohama 236-0004, Japan
| | - Roger Sciammas
- Center for Immunology and Infectious Diseases, University of California Davis, Davis, CA 95616, USA
| | - Philippe Bouvet
- Université de Lyon, Ecole Normale Supérieure de Lyon, Centre de Recherche en Cancérologie de Lyon, Cancer Cell Plasticity Department, UMR INSERM 1052 CNRS 5286, Centre Léon Bérard, Lyon, France
| | - Tapas K Kundu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India.
| | - Kazuhiko Igarashi
- Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan; Center for Regulatory Epigenome and Diseases, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan.
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LRRC8A-dependent volume-regulated anion channels contribute to ischemia-induced brain injury and glutamatergic input to hippocampal neurons. Exp Neurol 2020; 332:113391. [PMID: 32598930 DOI: 10.1016/j.expneurol.2020.113391] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Revised: 06/05/2020] [Accepted: 06/25/2020] [Indexed: 11/20/2022]
Abstract
Volume-regulated anion channels (VRACs) are critically involved in regulating cell volume, and leucine-rich repeat-containing protein 8A (LRRC8A, SWELL1) is an obligatory subunit of VRACs. Cell swelling occurs early after brain ischemia, but it is unclear whether neuronal LRRC8a contributes to ischemia-induced glutamate release and brain injury. We found that Lrrc8a conditional knockout (Lrrc8a-cKO) mice produced by crossing NestinCre+/- with Lrrc8aflox+/+ mice died 7-8 weeks of age, indicating an essential role of neuronal LRRC8A for survival. Middle cerebral artery occlusion (MCAO) caused an early increase in LRRC8A protein levels in the hippocampus in wild-type (WT) mice. Whole-cell patch-clamp recording in brain slices revealed that oxygen-glucose deprivation significantly increased the amplitude of VRAC currents in hippocampal CA1 neurons in WT but not in Lrrc8a-cKO mice. Hypotonicity increased the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) in hippocampal CA1 neurons in WT mice, and this was abolished by DCPIB, a VRAC blocker. But in Lrrc8a-cKO mice, hypotonic solution had no effect on the frequency of sEPSCs in these neurons. Furthermore, the brain infarct volume and neurological severity score induced by MCAO were significantly lower in Lrrc8a-cKO mice than in WT mice. In addition, MCAO-induced increases in cleaved caspase-3 and calpain activity, two biochemical markers of neuronal apoptosis and death, in brain tissues were significantly attenuated in Lrrc8a-cKO mice compared with WT mice. These new findings indicate that cerebral ischemia increases neuronal LRRC8A-dependent VRAC activity and that VRACs contribute to increased glutamatergic input to hippocampal neurons and brain injury caused by ischemic stroke.
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Sikder S, Kumari S, Kumar M, Sen S, Singhal NB, Chellappan S, Godbole M, Chandrani P, Dutt A, Gopinath KS, Kundu TK. Chromatin protein PC4 is downregulated in breast cancer to promote disease progression: Implications of miR-29a. Oncotarget 2019; 10:6855-6869. [PMID: 31839879 PMCID: PMC6901337 DOI: 10.18632/oncotarget.27325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 10/19/2019] [Indexed: 02/05/2023] Open
Abstract
The human transcriptional coactivator PC4 has numerous roles to play in the cell. Other than its transcriptional coactivation function, it facilitates chromatin organization, DNA damage repair, viral DNA replication, etc. Although it was found to be an essential protein in vivo, the importance of this multifunctional protein in the regulation of different cellular pathways has not been investigated in details, particularly in oncogenesis. In this study, PC4 downregulation was observed in a significant proportion of mammary tissues obtained from Breast cancer patient samples as well as in a subset of highly invasive and metastatic Breast cancer patient-derived cell lines. We have identified a miRNA, miR-29a which potentially reduce the expression of PC4 both in RNA and protein level. This miR-29a was found to be indeed overexpressed in a substantial number of Breast cancer patient samples and cell lines as well, suggesting one of the key mechanisms of PC4 downregulation. Stable Knockdown of PC4 in MCF7 cells induced its migratory as well as invasive properties. Furthermore, in an orthotopic breast cancer mice model system; we have shown that reduced expression of PC4 enhances the tumorigenic potential substantially. Absence of PC4 led to the upregulation of several genes involved in Epithelial to Mesenchymal Transition (EMT), indicating the possible mechanism of uniform tumour progression in the orthotropic mice. Collectively these data establish the role of PC4 in tumour suppression.
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Affiliation(s)
- Sweta Sikder
- 1Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Sujata Kumari
- 1Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Manoj Kumar
- 1Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Shrinka Sen
- 1Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | | | | | - Mukul Godbole
- 3Integrated Cancer Genomics Lab, Advanced Centre for Treatment, Research and Education in Cancer, Mumbai, India
| | - Pratik Chandrani
- 3Integrated Cancer Genomics Lab, Advanced Centre for Treatment, Research and Education in Cancer, Mumbai, India
| | - Amit Dutt
- 3Integrated Cancer Genomics Lab, Advanced Centre for Treatment, Research and Education in Cancer, Mumbai, India
| | | | - Tapas K. Kundu
- 1Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
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9
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Mondal P, Saleem S, Sikder S, Kundu TK, Biswas SC, Roy S. Multifunctional transcriptional coactivator PC4 is a global co-regulator of p53-dependent stress response and gene regulation. J Biochem 2019; 166:403-413. [PMID: 31236588 DOI: 10.1093/jb/mvz050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Accepted: 06/19/2019] [Indexed: 01/26/2023] Open
Abstract
Human positive coactivator 4 (PC4), a multifunctional chromatin-associated protein, is known to directly interact with p53 and modulate expressions of a few p53-dependent genes. However, the role of PC4 in p53's myriad of other regulatory functions is not known. The p53-PC4 interaction was selectively perturbed by a small peptide which led to abrogation of genotoxic stress-induced up-regulation of many p53-dependent genes and reduction of apoptosis in A549 cells. Over-expression of a PC4 point mutant, incapable of binding p53, recapitulated many of the effects of the peptide. Global gene expression profiling in A549 cells, upon peptide treatment, revealed PC4's involvement in the regulation of many p53-dependent pathways, including the Hippo pathway. Introduction of the peptide in neuronal cells significantly reduced its amyloid-β-induced death. Thus, PC4 emerges as a global co-regulator of p53 and a therapeutic target against pathogeneses where the p53-dependent cell death process plays a crucial role.
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Affiliation(s)
- Priya Mondal
- Department of Biophysics, Bose Institute, P1/12, CIT Scheme VIIM, Kolkata, West Bengal
| | - Suraiya Saleem
- Division of Cell Biology and Physiology, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, West Bengal
| | - Sweta Sikder
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka, India
| | - Tapas K Kundu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, Karnataka, India
| | - Subhas Chandra Biswas
- Division of Cell Biology and Physiology, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Kolkata, West Bengal
| | - Siddhartha Roy
- Department of Biophysics, Bose Institute, P1/12, CIT Scheme VIIM, Kolkata, West Bengal
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Abbott LC, Nigussie F. Adult neurogenesis in the mammalian dentate gyrus. Anat Histol Embryol 2019; 49:3-16. [PMID: 31568602 DOI: 10.1111/ahe.12496] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 06/03/2019] [Accepted: 08/22/2019] [Indexed: 12/30/2022]
Abstract
Earlier observations in neuroscience suggested that no new neurons form in the mature central nervous system. Evidence now indicates that new neurons do form in the adult mammalian brain. Two regions of the mature mammalian brain generate new neurons: (a) the border of the lateral ventricles of the brain (subventricular zone) and (b) the subgranular zone (SGZ) of the dentate gyrus of the hippocampus. This review focuses only on new neuron formation in the dentate gyrus of the hippocampus. During normal prenatal and early postnatal development, neural stem cells (NSCs) give rise to differentiated neurons. NSCs persist in the dentate gyrus SGZ, undergoing cell division, with some daughter cells differentiating into functional neurons that participate in learning and memory and general cognition through integration into pre-existing neural networks. Axons, which emanate from neurons in the entorhinal cortex, synapse with dendrites of the granule cells (small neurons) of the dentate gyrus. Axons from granule cells synapse with pyramidal cells in the hippocampal CA3 region, which send axons to synapse with CA1 hippocampal pyramidal cells that send their axons out of the hippocampus proper. Adult neurogenesis includes proliferation, differentiation, migration, the death of some newly formed cells and final integration of surviving cells into neural networks. We summarise these processes in adult mammalian hippocampal neurogenesis and discuss the roles of major signalling molecules that influence neurogenesis, including neurotransmitters and some hormones. The recent controversy raised concerning whether or not adult neurogenesis occurs in humans also is discussed.
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Affiliation(s)
- Louise C Abbott
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, USA
| | - Fikru Nigussie
- College of Veterinary Medicine, Oregon State University, Corvallis, OR, USA
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11
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Sikder S, Kumari S, Mustafi P, Ramdas N, Padhi S, Saha A, Bhaduri U, Banerjee B, Manjithaya R, Kundu TK. Nonhistone human chromatin protein PC4 is critical for genomic integrity and negatively regulates autophagy. FEBS J 2019; 286:4422-4442. [PMID: 31169983 DOI: 10.1111/febs.14952] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Revised: 05/13/2019] [Accepted: 06/04/2019] [Indexed: 12/28/2022]
Abstract
Multifunctional human transcriptional positive co-activator 4 (PC4) is a bona fide nonhistone component of the chromatin and plays a pivotal role in the process of chromatin compaction and functional genome organization. Knockdown of PC4 expression causes a drastic decompaction which leads to open conformation of the chromatin, and thereby altered nuclear architecture, defects in chromosome segregation and changed epigenetic landscape. Interestingly, these defects do not induce cellular death but result in enhanced cellular proliferation, possibly through enhanced autophagic activity. Moreover, PC4 depletion confers significant resistance to gamma irradiation. Exposure to gamma irradiation further induced autophagy in these cells. Inhibition of autophagy by small molecule inhibitors as well as by silencing of a critical autophagy gene drastically reduces the ability of PC4 knockdown cells to survive. On the contrary, complementation with wild-type PC4 could reverse this phenomenon, confirming the process of autophagy as the key mechanism for radiation resistance in the absence of PC4. These data connect the unexplored role of chromatin architecture in regulating autophagy during stress conditions such as radiation.
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Affiliation(s)
- Sweta Sikder
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Sujata Kumari
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Pallabi Mustafi
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Nisha Ramdas
- Mechanobiology Institute & Department of Biological Sciences, National University of Singapore, Singapore
| | - Swatishree Padhi
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Arka Saha
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Utsa Bhaduri
- Chromatin Biology Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Birendranath Banerjee
- Molecular Stress and Stem Cell Biology Group, School of Biotechnology, KIIT University, Bhubaneswar, India
| | - Ravi Manjithaya
- Autophagy Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
| | - Tapas K Kundu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore, India
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12
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Luo P, Jiang Q, Fang Q, Wang Y, Wang Z, Yang J, Tan X, Li W, Shi C. The human positive cofactor 4 promotes androgen-independent prostate cancer development and progression through HIF-1α/β-catenin pathway. Am J Cancer Res 2019; 9:682-698. [PMID: 31105996 PMCID: PMC6511634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 03/15/2019] [Indexed: 06/09/2023] Open
Abstract
Androgen-dependent prostate cancer (ADPC) eventually progresses to androgen-independent prostate cancer (AIPC), that has a poor prognosis owing to its unclear mechanism and lack of effective therapeutic targets. The human positive cofactor 4 (PC4) is a transcriptional cofactor, and plays a potential role in cancer development. However, the significance and mechanism of PC4 in AIPC progression are unclear. By analyzing the clinical data, we find that PC4 is overexpressed in prostate cancer and closely correlated with the progression, metastasis and prognosis of patients. Additionally, PC4 is significantly upregulated in AIPC cells compared with ADPC cells, implying its importance in the development and progression of AIPC. Then, in vivo and in vitro studies reveal that loss of PC4 inhibits cell growth by suppressing c-Myc/P21 pathway and inducing cell cycle arrest at G1/S phase transition in AIPC. PC4 knockdown also attenuates EMT-mediated metastasis in AIPC. Moreover, for the first time, we find that PC4 exerts its oncogenic functions by promoting the expression of HIF-1α and activating β-catenin signaling. Therefore, our findings determine the signatures and molecular mechanisms of PC4 in AIPC, and indicate that PC4 might be a promising therapeutic target for AIPC.
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Affiliation(s)
- Peng Luo
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
| | - Qingzhi Jiang
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
- Institute of Clinical Medicine, Southwest Medical UniversityLuzhou 646000, Sichuan, China
| | - Qiang Fang
- Department of Urology and Nephrology, The Third Affiliated Hospital of Chongqing Medical UniversityChongqing 401120, China
| | - Yawei Wang
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
| | - Ziwen Wang
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
| | - Jing Yang
- Institute of Pathology and Southwest Cancer Center, Southwest Hospital, Third Military Medical UniversityChongqing 400038, China
| | - Xu Tan
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
| | - Weibing Li
- Department of Urology and Nephrology, The Third Affiliated Hospital of Chongqing Medical UniversityChongqing 401120, China
| | - Chunmeng Shi
- Institute of Rocket Force Medicine, State Key Laboratory of Trauma, Burns and Combined Injury, Third Military Medical UniversityChongqing 400038, China
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13
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Zhang T, Liu X, Chen X, Wang J, Wang Y, Qian D, Pang Q, Wang P. Inhibition of PC4 radiosensitizes non-small cell lung cancer by transcriptionally suppressing XLF. Cancer Med 2018. [PMID: 29522271 PMCID: PMC5911594 DOI: 10.1002/cam4.1332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Positive cofactor 4 (PC4) participates in DNA damage repair and involved in nonhomologous end joining (NHEJ). Our previous results demonstrated that knockdown of PC4 downregulated the expression of XRCC4-like factor (XLF) in esophageal squamous cell carcinoma. However, the mechanism how PC4 regulates the expression of XLF remains unclear. Here, we found that knockdown of PC4 increased radiosensitivity of non-small cell lung cancer (NSCLC) both in vivo and in vitro. Furthermore, we found that PC4 knockdown downregulated the expression of XLF, whereas recovering XLF expression restored radioresistance in the PC4-knockdown NSCLC cells. In addition, PC4 knockdown inhibited XLF expression by transcriptionally suppressing of XLF. Moreover, PC4 expression correlated with radiosensitivity and was an independent prognostic factor of progression-free survival (PFS) in patients with NSCLC. These findings suggest that PC4 could be used as a promising therapeutic target for NSCLC.
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Affiliation(s)
- Tian Zhang
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Xiaojie Liu
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Xiuli Chen
- Department of Radiotherapy, Tianjin Hospital, Tianjin, China
| | - Jing Wang
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Yuwen Wang
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Dong Qian
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Qingsong Pang
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - Ping Wang
- Department of Radiotherapy, National Clinical Research Center for Cancer, Tianjin's Clinical Research Center for Cancer, Key Laboratory of Cancer Prevention and Therapy, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
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14
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Kuttapitiya A, Assi L, Laing K, Hing C, Mitchell P, Whitley G, Harrison A, Howe FA, Ejindu V, Heron C, Sofat N. Microarray analysis of bone marrow lesions in osteoarthritis demonstrates upregulation of genes implicated in osteochondral turnover, neurogenesis and inflammation. Ann Rheum Dis 2017; 76:1764-1773. [PMID: 28705915 PMCID: PMC5629942 DOI: 10.1136/annrheumdis-2017-211396] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/05/2017] [Accepted: 06/05/2017] [Indexed: 12/12/2022]
Abstract
Objective Bone marrow lesions (BMLs) are well described in osteoarthritis (OA) using MRI and are associated with pain, but little is known about their pathological characteristics and gene expression. We evaluated BMLs using novel tissue analysis tools to gain a deeper understanding of their cellular and molecular expression. Methods We recruited 98 participants, 72 with advanced OA requiring total knee replacement (TKR), 12 with mild OA and 14 non-OA controls. Participants were assessed for pain (using Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)) and with a knee MRI (using MOAKS). Tissue was then harvested at TKR for BML analysis using histology and tissue microarray. Results The mean (SD) WOMAC pain scores were significantly increased in advanced OA 59.4 (21.3) and mild OA 30.9 (20.3) compared with controls 0.5 (1.28) (p<0.0001). MOAKS showed all TKR tissue analysed had BMLs, and within these lesions, bone marrow volume was starkly reduced being replaced by dense fibrous connective tissue, new blood vessels, hyaline cartilage and fibrocartilage. Microarray comparing OA BML and normal bone found a significant difference in expression of 218 genes (p<0.05). The most upregulated genes included stathmin 2, thrombospondin 4, matrix metalloproteinase 13 and Wnt/Notch/catenin/chemokine signalling molecules that are known to constitute neuronal, osteogenic and chondrogenic pathways. Conclusion Our study is the first to employ detailed histological analysis and microarray techniques to investigate knee OA BMLs. BMLs demonstrated areas of high metabolic activity expressing pain sensitisation, neuronal, extracellular matrix and proinflammatory signalling genes that may explain their strong association with pain.
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Affiliation(s)
- Anasuya Kuttapitiya
- Institute for Infection & Immunity, St George's, University of London, London, UK
| | - Lena Assi
- Institute for Infection & Immunity, St George's, University of London, London, UK
| | - Ken Laing
- Institute for Infection & Immunity, St George's, University of London, London, UK
| | - Caroline Hing
- St George's University Hospitals NHS Foundation Trust, London, UK
| | - Philip Mitchell
- St George's University Hospitals NHS Foundation Trust, London, UK
| | - Guy Whitley
- Institute for Molecular and Clinical Sciences, St George's, University of London, London, UK
| | - Abiola Harrison
- Institute for Infection & Immunity, St George's, University of London, London, UK
| | - Franklyn A Howe
- Institute for Molecular and Clinical Sciences, St George's, University of London, London, UK
| | - Vivian Ejindu
- St George's University Hospitals NHS Foundation Trust, London, UK
| | - Christine Heron
- St George's University Hospitals NHS Foundation Trust, London, UK
| | - Nidhi Sofat
- Institute for Infection & Immunity, St George's, University of London, London, UK
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15
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Griffin WC, Gao J, Byrd AK, Chib S, Raney KD. A biochemical and biophysical model of G-quadruplex DNA recognition by positive coactivator of transcription 4. J Biol Chem 2017; 292:9567-9582. [PMID: 28416612 DOI: 10.1074/jbc.m117.776211] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 04/14/2017] [Indexed: 12/22/2022] Open
Abstract
DNA sequences that are guanine-rich have received considerable attention because of their potential to fold into a secondary, four-stranded DNA structure termed G-quadruplex (G4), which has been implicated in genomic instability and some human diseases. We have previously identified positive coactivator of transcription (PC4), a single-stranded DNA (ssDNA)-binding protein, as a novel G4 interactor. Here, to expand on these previous observations, we biochemically and biophysically characterized the interaction between PC4 and G4DNA. PC4 can bind alternative G4DNA topologies with a low nanomolar Kd value of ∼2 nm, similar to that observed for ssDNA. In consideration of the different structural features between G4DNA and ssDNA, these binding data indicated that PC4 can interact with G4DNA in a manner distinct from ssDNA. The stoichiometry of the PC4-G4 complex was 1:1 for PC4 dimer:G4 substrate. PC4 did not enhance the rate of folding of G4DNA, and formation of the PC4-G4DNA complex did not result in unfolding of the G4DNA structure. We assembled a G4DNA structure flanked by duplex DNA. We find that PC4 can interact with this G4DNA, as well as the complementary C-rich strand. Molecular docking simulations and DNA footprinting experiments suggest a model where a PC4 dimer accommodates the DNA with one monomer on the G4 strand and the second monomer bound to the C-rich strand. Collectively, these data provide a novel mode of PC4 binding to a DNA secondary structure that remains within the framework of the model for binding to ssDNA. Additionally, consideration of the PC4-G4DNA interaction could provide insight into the biological functions of PC4, which remain incompletely understood.
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Affiliation(s)
- Wezley C Griffin
- From the Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7101
| | - Jun Gao
- From the Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7101
| | - Alicia K Byrd
- From the Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7101
| | - Shubeena Chib
- From the Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7101
| | - Kevin D Raney
- From the Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-7101
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