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Jung S, Koo KM, Ryu J, Baek I, Kwon SJ, Kim JB, Ahn JW. Overexpression of Phosphoribosyl Pyrophosphate Synthase Enhances Resistance of Chlamydomonas to Ionizing Radiation. FRONTIERS IN PLANT SCIENCE 2021; 12:719846. [PMID: 34512699 PMCID: PMC8427504 DOI: 10.3389/fpls.2021.719846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 07/29/2021] [Indexed: 06/13/2023]
Abstract
The enzyme phosphoribosyl pyrophosphate synthase (PRPS) catalyzes the conversion of ribose 5-phosphate into phosphoribosyl diphosphate; the latter is a precursor of purine and pyrimidine nucleotides. Here, we investigated the function of PRPS from the single-celled green alga Chlamydomonas reinhardtii in its response to DNA damage from gamma radiation or the alkylating agent LiCl. CrPRPS transcripts were upregulated in cells treated with these agents. We generated CrPRPS-overexpressing transgenic lines to study the function of CrPRPS. When grown in culture with LiCl or exposed to gamma radiation, the transgenic cells grew faster and had a greater survival rate than wild-type cells. CrPRPS overexpression enhanced expression of genes associated with DNA damage response, namely RAD51, RAD1, and LIG1. We observed, from transcriptome analysis, upregulation of genes that code for key enzymes in purine metabolism, namely ribonucleoside-diphosphate pyrophosphokinase subunit M1, adenylate kinase, and nucleoside-diphosphate kinase. We conclude that CrPRPS may affect DNA repair process via regulation of de novo nucleotide synthesis.
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Affiliation(s)
- Sera Jung
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
- Advanced Process Technology and Fermentation Research Group, Research and Development Division, World Institute of Kimchi, Jeongeup-si, South Korea
| | - Kwang Min Koo
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
| | - Jaihyunk Ryu
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
| | - Inwoo Baek
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
| | - Soon-Jae Kwon
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
| | - Jin-Baek Kim
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
| | - Joon-Woo Ahn
- Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, South Korea
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2
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Jessulat M, Amin S, Hooshyar M, Malty R, Moutaoufik MT, Zilocchi M, Istace Z, Phanse S, Aoki H, Omidi K, Burnside D, Samanfar B, Aly KA, Golshani A, Babu M. The conserved Tpk1 regulates non-homologous end joining double-strand break repair by phosphorylation of Nej1, a homolog of the human XLF. Nucleic Acids Res 2021; 49:8145-8160. [PMID: 34244791 PMCID: PMC8373142 DOI: 10.1093/nar/gkab585] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 06/13/2021] [Accepted: 06/24/2021] [Indexed: 02/03/2023] Open
Abstract
The yeast cyclic AMP-dependent protein kinase A (PKA) is a ubiquitous serine-threonine kinase, encompassing three catalytic (Tpk1-3) and one regulatory (Bcy1) subunits. Evidence suggests PKA involvement in DNA damage checkpoint response, but how DNA repair pathways are regulated by PKA subunits remains inconclusive. Here, we report that deleting the tpk1 catalytic subunit reduces non-homologous end joining (NHEJ) efficiency, whereas tpk2-3 and bcy1 deletion does not. Epistatic analyses revealed that tpk1, as well as the DNA damage checkpoint kinase (dun1) and NHEJ factor (nej1), co-function in the same pathway, and parallel to the NHEJ factor yku80. Chromatin immunoprecipitation and resection data suggest that tpk1 deletion influences repair protein recruitments and DNA resection. Further, we show that Tpk1 phosphorylation of Nej1 at S298 (a Dun1 phosphosite) is indispensable for NHEJ repair and nuclear targeting of Nej1 and its binding partner Lif1. In mammalian cells, loss of PRKACB (human homolog of Tpk1) also reduced NHEJ efficiency, and similarly, PRKACB was found to phosphorylate XLF (a Nej1 human homolog) at S263, a corresponding residue of the yeast Nej1 S298. Together, our results uncover a new and conserved mechanism for Tpk1 and PRKACB in phosphorylating Nej1 (or XLF), which is critically required for NHEJ repair.
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Affiliation(s)
- Matthew Jessulat
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Shahreen Amin
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Mohsen Hooshyar
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1S5 B6, Canada
| | - Ramy Malty
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | | | - Mara Zilocchi
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Zoe Istace
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Sadhna Phanse
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Hiroyuki Aoki
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Katayoun Omidi
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1S5 B6, Canada
| | - Daniel Burnside
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1S5 B6, Canada
| | - Bahram Samanfar
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1S5 B6, Canada
| | - Khaled A Aly
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
| | - Ashkan Golshani
- Department of Biology, Carleton University, Ottawa, Ontario K1S 5B6, Canada.,Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario K1S5 B6, Canada
| | - Mohan Babu
- Department of Biochemistry, University of Regina, Regina, Saskatchewan S4S 0A2, Canada
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3
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Su L, Yang C, Meng J, Zhou L, Zhang C. Comparative transcriptome and metabolome analysis of Ostrinia furnacalis female adults under UV-A exposure. Sci Rep 2021; 11:6797. [PMID: 33762675 PMCID: PMC7990960 DOI: 10.1038/s41598-021-86269-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 03/08/2021] [Indexed: 01/31/2023] Open
Abstract
Ultraviolet A (UV-A) radiation is a significant environmental factor that causes photoreceptor damage, apoptosis, and oxidative stress in insects. Ostrinia furnacalis is an important pest of corn. To understand the adaptation mechanisms of insect response to UV-A exposure, this study revealed differentially expressed genes (DEGs) and differently expressed metabolites (DEMs) in O. furnacalis under UV-A exposure. Three complementary DNA libraries were constructed from O. furnacalis adult females (CK, UV1h, and UV2h), and 50,106 expressed genes were obtained through Illumina sequencing. Of these, 157 and 637 DEGs were detected in UV1h and UV2h after UV-A exposure for 1 and 2 h, respectively, compared to CK, with 103 and 444 upregulated and 54 and 193 downregulated genes, respectively. Forty four DEGs were detected in UV2h compared to UV1h. Comparative transcriptome analysis between UV-treated and control groups revealed signal transduction, detoxification and stress response, immune defense, and antioxidative system involvement. Metabolomics analysis showed that 181 (UV1h vs. CK), 111 (UV2h vs. CK), and 34 (UV2h vs. UV1h) DEMs were obtained in positive ion mode, while 135 (UV1h vs. CK), 93 (UV2h vs. CK), and 36 (UV2h vs. UV1h) DEMs were obtained in negative ion mode. Moreover, UV-A exposure disturbed amino acid, sugar, and lipid metabolism. These findings provide insight for further studies on how insects protect themselves under UV-A stress.
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Affiliation(s)
- Li Su
- grid.443382.a0000 0004 1804 268XInstitute of Entomology, Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Guizhou University, Guiyang, 550025 People’s Republic of China
| | - Changli Yang
- grid.443382.a0000 0004 1804 268XInstitute of Entomology, Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Guizhou University, Guiyang, 550025 People’s Republic of China
| | - Jianyu Meng
- Guizhou Tobacco Science Research Institute, Guiyang, 550081 People’s Republic of China
| | - Lv Zhou
- grid.443382.a0000 0004 1804 268XInstitute of Entomology, Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Guizhou University, Guiyang, 550025 People’s Republic of China
| | - Changyu Zhang
- grid.443382.a0000 0004 1804 268XInstitute of Entomology, Provincial Key Laboratory for Agricultural Pest Management of Mountainous Regions, Guizhou University, Guiyang, 550025 People’s Republic of China
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Vahidi Ferdowsi P, Ng R, Adulcikas J, Sohal SS, Myers S. Zinc Modulates Several Transcription-Factor Regulated Pathways in Mouse Skeletal Muscle Cells. Molecules 2020; 25:E5098. [PMID: 33153045 PMCID: PMC7663025 DOI: 10.3390/molecules25215098] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 10/28/2020] [Indexed: 02/07/2023] Open
Abstract
Zinc is an essential metal ion involved in many biological processes. Studies have shown that zinc can activate several molecules in the insulin signalling pathway and the concomitant uptake of glucose in skeletal muscle cells. However, there is limited information on other potential pathways that zinc can activate in skeletal muscle. Accordingly, this study aimed to identify other zinc-activating pathways in skeletal muscle cells to further delineate the role of this metal ion in cellular processes. Mouse C2C12 skeletal muscle cells were treated with insulin (10 nM), zinc (20 µM), and the zinc chelator TPEN (various concentrations) over 60 min. Western blots were performed for the zinc-activation of pAkt, pErk, and pCreb. A Cignal 45-Reporter Array that targets 45 signalling pathways was utilised to test the ability of zinc to activate pathways that have not yet been described. Zinc and insulin activated pAkt over 60 min as expected. Moreover, the treatment of C2C12 skeletal muscle cells with TPEN reduced the ability of zinc to activate pAkt and pErk. Zinc also activated several associated novel transcription factor pathways including Nrf1/Nrf2, ATF6, CREB, EGR1, STAT1, AP-1, PPAR, and TCF/LEF, and pCREB protein over 120 min of zinc treatment. These studies have shown that zinc's activity extends beyond that of insulin signalling and plays a role in modulating novel transcription factor activated pathways. Further studies to determine the exact role of zinc in the activation of transcription factor pathways will provide novel insights into this metal ion actions.
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Affiliation(s)
| | | | | | | | - Stephen Myers
- College of Health and Medicine, School of Health Sciences, University of Tasmania, Newnham Campus, Launceston 7250, Australia; (P.V.F.); (R.N.); (J.A.); (S.S.S.)
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5
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Bouchet N, Jaillet J, Gabant G, Brillet B, Briseño-Roa L, Cadene M, Augé-Gouillou C. cAMP protein kinase phosphorylates the Mos1 transposase and regulates its activity: evidences from mass spectrometry and biochemical analyses. Nucleic Acids Res 2014; 42:1117-28. [PMID: 24081583 PMCID: PMC3902898 DOI: 10.1093/nar/gkt874] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 09/05/2013] [Accepted: 09/06/2013] [Indexed: 12/19/2022] Open
Abstract
Genomic plasticity mediated by transposable elements can have a dramatic impact on genome integrity. To minimize its genotoxic effects, it is tightly regulated either by intrinsic mechanisms (linked to the element itself) or by host-mediated mechanisms. Using mass spectrometry, we show here for the first time that MOS1, the transposase driving the mobility of the mariner Mos1 element, is phosphorylated. We also show that the transposition activity of MOS1 is downregulated by protein kinase AMP cyclic-dependent phosphorylation at S170, which renders the transposase unable to promote Mos1 transposition. One step in the transposition cycle, the assembly of the paired-end complex, is specifically inhibited. At the cellular level, we provide evidence that phosphorylation at S170 prevents the active transport of the transposase into the nucleus. Our data suggest that protein kinase AMP cyclic-dependent phosphorylation may play a double role in the early stages of genome invasion by mariner elements.
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Affiliation(s)
- Nicolas Bouchet
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Jérôme Jaillet
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Guillaume Gabant
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Benjamin Brillet
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Luis Briseño-Roa
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Martine Cadene
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
| | - Corinne Augé-Gouillou
- Innovation Moléculaire Thérapeutique, EA 6306, UFR Sciences Pharmaceutiques, Parc Grandmont, Université François Rabelais, 37200 Tours, France, Centre de Biophysique Moléculaire, UPR 4301 CNRS, Rue Charles Sadron, 45071 Orléans, France, Laboratoire Universitaire de Biodiversité et Ecologie Microbienne, IUT de Quimper, Université de Bretagne Occidentale, 6 rue de l’Université, 29000 Quimper, France and Biologie Cellulaire de la Synapse, INSERM U789, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
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6
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Wang Z, Wang G, Yang J, Guo L, Yu Y. Activation of protein kinase A and clustering of cell surface receptors by N-methyl-N'-nitro-N-nitrosoguanidine are independent of genomic DNA damage. Mutat Res 2003; 528:29-36. [PMID: 12873720 DOI: 10.1016/s0027-5107(03)00079-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Alkylating agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induces cellular stress leading to chromosomal aberrations, mutations and cell death. Previous reports from our laboratory have shown that low concentration of MNNG induces untargeted mutation (UTM), which occurs on intact DNA in mammalian cells through changes in gene expression profile. It also causes the activation of cAMP-protein kinase A (PKA) and up-regulation of POL-beta, which is demonstrated to play a role in DNA repair system. In order to find out the possible initial signal involved in UTM, we try to investigate whether the activation of PKA-CREB signal pathway is closely related to DNA damage. Our data shows that the treatment of low concentration MNNG (0.2 microM) activates PKA-CREB pathway in a comparable level both in a nuclear and enucleated cell system. And similar to the cell response caused by UV, the clustering of cell surface receptors of epidermal growth factor (EGF) and tumor necrosis factor alpha (TNFalpha) was also observed in cells exposed to MNNG. It was further demonstrated that the clustering of the surface receptors is independent of the genomic DNA damage, as this phenomenon was also observed in enucleated cells. These observations indicate that the initiation of signal cascades induced by low concentration of MNNG might be associated with its interaction with cell surface receptors and/or direct activation of related signal proteins but not its DNA damaging property.
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Affiliation(s)
- Zheng Wang
- Department of Pathophysiology, School of Medicine, Zhejiang University, Hangzhou, 310031 Zhejiang, China
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7
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Yacoub A, McKinstry R, Hinman D, Chung T, Dent P, Hagan MP. Epidermal growth factor and ionizing radiation up-regulate the DNA repair genes XRCC1 and ERCC1 in DU145 and LNCaP prostate carcinoma through MAPK signaling. Radiat Res 2003; 159:439-52. [PMID: 12643788 DOI: 10.1667/0033-7587(2003)159[0439:egfair]2.0.co;2] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This work examined the importance of radiation-induced and ligand-induced EGFR-ERK signaling for the regulation of DNA repair proteins XRCC1 and ERCC1 in prostate carcinoma cells, DU145 (TP53(mut)), displaying EGFR-TGFA-dependent autocrine growth and high MAPK (ERK1/2) activity, and LNCaP (TP53(wt)) cells expressing low constitutive levels of ERK1/2 activity. Using quantitative RT-PCR and Western analyses, we determined that ionizing radiation activated the DNA repair genes XRCC1 and ERCC1 in an ERK1/2-dependent fashion for each cell line. After irradiation, a rapid increase followed by a decrease in ERK1/2 activity preceded the increase in XRCC1/ERCC1 expression in DU145 cells, while only the rapid decrease in ERK1/2 preceded the increase in XRCC1/ERCC1 expression in LNCaP cells. Administration of EGF, however, markedly increased the up-regulation of phospho-ERK, ERCC1 and XRCC1 in both cell lines. Although the EGFR inhibitor tyrphostin (AG-1478) and the MEK inhibitor PD90859 both attenuated EGF-induced levels of the ERCC1 and XRCC1 protein, PD98059 blocked the induction of ERCC1 and XRCC1 by radiation more effectively in both cell lines. Inhibition of ERK at a level that reduced the up-regulation of DNA repair led to the persistence of apurinic/apyrimidinic (AP) sites of DNA damage and increased cell killing. Taken together, these data imply a complex control of DNA repair activation that may be more generally dependent on MAPK (ERK1/2) signaling than was previously noted. These data provide novel insights into the capacity of the EGFR-ERK signaling to modulate DNA repair in cancer cells and into the functional significance of this signaling.
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Affiliation(s)
- Adly Yacoub
- Department of Radiation Oncology, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia 23298, USA
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Nguyen DT, Rovira II, Finkel T. Regulation of the Werner helicase through a direct interaction with a subunit of protein kinase A. FEBS Lett 2002; 521:170-4. [PMID: 12067711 DOI: 10.1016/s0014-5793(02)02868-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Werner syndrome is a hereditary disease characterized by cancer predisposition, genetic instability, and the premature appearance of features associated with normal aging. At the molecular level this syndrome has been related to mutations in the Werner helicase, a member of the RecQ family of DNA helicases which are required to maintain genomic stability in cells. Here we show by a yeast two-hybrid screen that the Werner helicase can directly interact with the regulatory subunit (RIbeta) of cAMP protein kinase A (PKA). We confirm that this interaction occurs in vivo. Interestingly, serum withdrawal causes a redistribution of the Werner helicase within the nucleus of mammalian cells. Raising intracellular cAMP levels or increased expression of the regulatory but not the catalytic subunit of PKA inhibits this nuclear redistribution stimulated by serum deprivation. These results suggest that similar to lower organisms, gene products linked to genomic instability and aging may be directly regulated by growth factor-sensitive, PKA-dependent pathways.
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Affiliation(s)
- Duy T Nguyen
- Cardiovascular Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bldg 10/6N-240, 10 Center Drive, Bethesda, MD 20892-1622, USA
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