seqA

Summary

Gene Symbol: seqA
Description: negative modulator of initiation of replication
Alias: ECK0675, JW0674, hsm-1
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. ncbi The assembly and migration of SeqA-Gfp fusion in living cells of Escherichia coli
    T Onogi
    Department of Molecular Cell Biology, Kumamoto University School of Medicine, Japan
    Mol Microbiol 31:1775-82. 1999
  2. ncbi The Escherichia coli SeqA protein destabilizes mutant DnaA204 protein
    N K Torheim
    Departments of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Mol Microbiol 37:629-38. 2000
  3. pmc Escherichia coli cell cycle control genes affect chromosome superhelicity
    T Weitao
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Sweden
    EMBO Rep 1:494-9. 2000
  4. pmc SeqA blocking of DnaA-oriC interactions ensures staged assembly of the E. coli pre-RC
    Christian Nievera
    Department of Biological Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, Florida 32901 USA
    Mol Cell 24:581-92. 2006
  5. ncbi Specific N-terminal interactions of the Escherichia coli SeqA protein are required to form multimers that restrain negative supercoils and form foci
    Ingvild Odsbu
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Genes Cells 10:1039-49. 2005
  6. ncbi Eclipse period without sequestration in Escherichia coli
    Jan Olsson
    Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Box 596, SE 751 24 Uppsala, Sweden
    Mol Microbiol 44:1429-40. 2002
  7. ncbi Insights into negative modulation of E. coli replication initiation from the structure of SeqA-hemimethylated DNA complex
    Alba Guarné
    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
    Nat Struct Biol 9:839-43. 2002
  8. ncbi Sequential binding of SeqA to paired hemi-methylated GATC sequences mediates formation of higher order complexes
    Joo Seok Han
    Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 278:34983-9. 2003
  9. ncbi SeqA protein stimulates the relaxing and decatenating activities of topoisomerase IV
    Sukhyun Kang
    Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 278:48779-85. 2003
  10. pmc Structural and biochemical analyses of hemimethylated DNA binding by the SeqA protein
    Norie Fujikawa
    RIKEN Genomic Sciences Center, 1 7 22 Suehiro cho, Tsurumi, Yokohama 230 0045, Japan
    Nucleic Acids Res 32:82-92. 2004

Research Grants

Scientific Experts

  • D Daghfous
  • V Norris
  • K Skarstad
  • S Hiraga
  • Alba Guarné
  • A Kuzminov
  • Erik Boye
  • Daghfous Douraid
  • Jolanta Zakrzewska-Czerwinska
  • Kurt Nordström
  • JON KAGUNI
  • Sukhyun Kang
  • Ella Rotman
  • Joo Seok Han
  • Grzegorz Wegrzyn
  • Ingvild Odsbu
  • Susan T Lovett
  • Torsten Waldminghaus
  • - Morigen
  • Solveig Fossum
  • Deog Su Hwang
  • Vincent A Sutera
  • James J Foti
  • Trond Bach
  • Alicja Wegrzyn
  • Mitsuyoshi Yamazoe
  • Norie Fujikawa
  • Daniel J Ferullo
  • M Kohiyama
  • H Lee
  • T Brendler
  • Mohan C Joshi
  • S Kang
  • M Yamazoe
  • S DasGupta
  • T Weitao
  • Kathryn L Molt
  • Magdalena M Felczak
  • Yu Seon Chung
  • T Onogi
  • Ana Babic
  • Robert Lyzeń
  • E Reshetnyak
  • Keith Champion
  • Stuart Austin
  • Magdalena Narajczyk
  • Therese Brendler
  • Agnieszka Szalewska-Pałasz
  • Aleksandra E Sikora
  • Robert Łyzeń
  • Elliott Crooke
  • Christian Nievera
  • D S Hwang
  • Sung Ho Kim
  • R Kern
  • Johanna E Camara
  • Jong Hoon Park
  • A Taghbalout
  • Elena A Kouzminova
  • U von Freiesleben
  • Felipe Molina
  • Hege Kjellesvik Klungsøyr
  • Hanjing Yang
  • Hitoshi Kurumizaka
  • Shigeyuki Yokoyama
  • Monika Słomińska
  • Jan A Olsson
  • Monika Slominska
  • Santanu Dasgupta
  • Jan Olsson
  • Jason Correnti
  • S Austin
  • Sharik R Khan
  • Elena Kouzminova
  • Nicholas Stepankiw
  • Timothy P Montminy
  • David Bates
  • Mark Lies
  • David Magnan
  • M Slominska
  • Christoph Weigel
  • A Malki
  • K Ohsumi
  • S Wold
  • A Løbner-Olesen
  • N K Torheim
  • T A Azam
  • H Niki
  • Preston Bratcher
  • Kathryn K Moore

Detail Information

Publications89

  1. ncbi The assembly and migration of SeqA-Gfp fusion in living cells of Escherichia coli
    T Onogi
    Department of Molecular Cell Biology, Kumamoto University School of Medicine, Japan
    Mol Microbiol 31:1775-82. 1999
    b>SeqA protein, which binds to hemi-methylated GATC sequences of DNA, is localized to discrete fluorescent foci in wild-type Escherichia coli cells. In this work, we observed cellular localization of the SeqA-Gfp fusion in living cells...
  2. ncbi The Escherichia coli SeqA protein destabilizes mutant DnaA204 protein
    N K Torheim
    Departments of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Mol Microbiol 37:629-38. 2000
    ..The reason for the DnaA protein deficiency was found to be a rapid degradation of the mutant protein. Absence of SeqA protein stabilized the DnaA204 protein, increased the DnaA protein concentration and normalized the initiation mass ..
  3. pmc Escherichia coli cell cycle control genes affect chromosome superhelicity
    T Weitao
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Sweden
    EMBO Rep 1:494-9. 2000
    ..supercoiling of Escherichia coli chromosome caused by mutations inactivating the cell cycle functions mukB and seqA. The amounts of the intercalative agent required to relax the supercoiled chromosome in mukB and seqA mutants were ..
  4. pmc SeqA blocking of DnaA-oriC interactions ensures staged assembly of the E. coli pre-RC
    Christian Nievera
    Department of Biological Sciences, Florida Institute of Technology, 150 West University Boulevard, Melbourne, Florida 32901 USA
    Mol Cell 24:581-92. 2006
    ..After initiation, SeqA binds to hemimethylated oriC, sequestering oriC while levels of active DnaA are reduced, preventing reinitiation...
  5. ncbi Specific N-terminal interactions of the Escherichia coli SeqA protein are required to form multimers that restrain negative supercoils and form foci
    Ingvild Odsbu
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Genes Cells 10:1039-49. 2005
    The Escherichia coli SeqA protein binds preferentially to hemimethylated DNA and is required for inactivation (sequestration) of newly formed origins...
  6. ncbi Eclipse period without sequestration in Escherichia coli
    Jan Olsson
    Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Box 596, SE 751 24 Uppsala, Sweden
    Mol Microbiol 44:1429-40. 2002
    ..For strains with seqA, dam and damseqA mutants, the length of the eclipse period was 0.16, 0.40 and 0.32 generation times respectively...
  7. ncbi Insights into negative modulation of E. coli replication initiation from the structure of SeqA-hemimethylated DNA complex
    Alba Guarné
    Laboratory of Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
    Nat Struct Biol 9:839-43. 2002
    The SeqA protein binds clusters of fully methylated or hemimethylated GATC sequences at oriC and negatively modulates the initiation of DNA replication...
  8. ncbi Sequential binding of SeqA to paired hemi-methylated GATC sequences mediates formation of higher order complexes
    Joo Seok Han
    Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 278:34983-9. 2003
    Preferential binding of the SeqA protein to hemi-methylated GATC sequences functions as a negative regulator for Escherichia coli initiation of chromosomal replication at oriC and is implicated in segregating replicated chromosomes for ..
  9. ncbi SeqA protein stimulates the relaxing and decatenating activities of topoisomerase IV
    Sukhyun Kang
    Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 278:48779-85. 2003
    The SeqA protein, which prevents overinitiation of chromosome replication, has been suggested to also participate in the segregation of chromosomes in Escherichia coli...
  10. pmc Structural and biochemical analyses of hemimethylated DNA binding by the SeqA protein
    Norie Fujikawa
    RIKEN Genomic Sciences Center, 1 7 22 Suehiro cho, Tsurumi, Yokohama 230 0045, Japan
    Nucleic Acids Res 32:82-92. 2004
    The Escherichia coli SeqA protein recognizes the 11 hemimethylated G-mA-T-C sites in the oriC region of the chromosome, and prevents replication over-initiation within one cell cycle...
  11. ncbi Replication fork and SeqA focus distributions in Escherichia coli suggest a replication hyperstructure dependent on nucleotide metabolism
    Felipe Molina
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Mol Microbiol 52:1597-612. 2004
    ..of cells growing with four different growth and replication rates, and compared these with the distributions of SeqA foci...
  12. ncbi Positive supercoiling is generated in the presence of Escherichia coli SeqA protein
    Hege Kjellesvik Klungsøyr
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Mol Microbiol 54:123-31. 2004
    In Escherichia coli, the SeqA protein is known as a negative regulator of chromosome replication. This protein is also suggested to have a role in chromosome organization...
  13. pmc RecA-dependent mutants in Escherichia coli reveal strategies to avoid chromosomal fragmentation
    Elena A Kouzminova
    Department of Microbiology, University of Illinois at Urbana Champaign, Urbana, IL 61801 3709, USA
    Proc Natl Acad Sci U S A 101:16262-7. 2004
    ..The fur, ubiE, and ubiH mutants are likely to have increased levels of reactive oxygen species. The seqA, topA mutants and an insertion in smtA perturbing the downstream mukFEB genes affect nucleoid administration...
  14. ncbi Sequential binding of SeqA protein to nascent DNA segments at replication forks in synchronized cultures of Escherichia coli
    Mitsuyoshi Yamazoe
    Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Konoe, Yoshida, Sakyo ku, Kyoto 606 8501, Japan
    Mol Microbiol 55:289-98. 2005
    To demonstrate that sequestration A (SeqA) protein binds preferentially to hemimethylated GATC sequences at replication forks and forms clusters in Escherichia coli growing cells, we analysed, by the chromatin immunoprecipitation (ChIP) ..
  15. ncbi A bacterial G protein-mediated response to replication arrest
    James J Foti
    Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454 9110, USA
    Mol Cell 17:549-60. 2005
    ..ObgE overexpression caused SeqA foci, normally localized to replication forks, to spread extensively within the cell...
  16. pmc Dimeric configuration of SeqA protein bound to a pair of hemi-methylated GATC sequences
    Sukhyun Kang
    Institute of Molecular Biology and Genetics, Seoul National University Seoul 151 742, Republic of Korea
    Nucleic Acids Res 33:1524-31. 2005
    The binding of SeqA protein to hemi-methylated GATC sequences (hemi-sites) regulates chromosome initiation and the segregation of replicated chromosome in Escherichia coli...
  17. pmc Crystal structure of a SeqA-N filament: implications for DNA replication and chromosome organization
    Alba Guarné
    Laboratory of Molecular Biology, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
    EMBO J 24:1502-11. 2005
    Escherichia coli SeqA binds clusters of transiently hemimethylated GATC sequences and sequesters the origin of replication, oriC, from methylation and premature reinitiation...
  18. ncbi Lack of SeqA focus formation, specific DNA binding and proper protein multimerization in the Escherichia coli sequestration mutant seqA2
    Solveig Fossum
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Mol Microbiol 47:619-32. 2003
    ..mutants discovered in a screen for the inability to sequester hemimethylated origins have been mapped to the seqA gene...
  19. ncbi The role of replication initiation control in promoting survival of replication fork damage
    Vincent A Sutera
    Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454 9110, USA
    Mol Microbiol 60:229-39. 2006
    ..Dam's role in tolerance of DNA damage is to provide binding sites for SeqA, because seqA mutants showed similar sensitivity that was genetically epistatic to dam...
  20. ncbi DnaA: controlling the initiation of bacterial DNA replication and more
    Jon M Kaguni
    Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824 1319, USA
    Annu Rev Microbiol 60:351-75. 2006
    ..A major player in this pathway is SeqA protein and involves its ability to bind preferentially to oriC when it is hemi-methylated...
  21. ncbi Aggregation of SeqA protein requires positively charged amino acids in the hinge region
    Sukhyun Kang
    Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151 742, Republic of Korea
    Biochem Biophys Res Commun 360:63-9. 2007
    b>SeqA proteins of Escherichia coli bound to the hemimethylated GATC sequences (hemi-sites) interact with each other and eventually form an aggregate...
  22. doi Direct visualization of horizontal gene transfer
    Ana Babic
    INSERM U571, Paris F 75015, France
    Science 319:1533-6. 2008
    ..Using a fluorescent protein fusion, SeqA-YFP, we have visualized this process in real time and in single cells of Escherichia coli...
  23. doi The initiator protein DnaA contributes to keeping new origins inactivated by promoting the presence of hemimethylated DNA
    Trond Bach
    Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Rikshospitalet, University of Oslo, 0310 Oslo, Norway
    J Mol Biol 384:1076-85. 2008
    ..The prolonged period of hemimethylation has been attributed to the presence of bound SeqA protein...
  24. pmc The stringent response and cell cycle arrest in Escherichia coli
    Daniel J Ferullo
    Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA, USA
    PLoS Genet 4:e1000300. 2008
    ..Arrest of replication and inhibition of colony formation by ppGpp accumulation is relieved in seqA and dam mutants, although other aspects of the stringent response appear to be intact...
  25. doi The Escherichia coli SeqA protein
    Torsten Waldminghaus
    Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Rikshospitalet, University of Oslo, 0310 Oslo, Norway
    Plasmid 61:141-50. 2009
    The Escherichia coli SeqA protein contributes to regulation of chromosome replication by preventing re-initiation at newly replicated origins. SeqA protein binds to new DNA which is hemimethylated at the adenine of GATC sequences...
  26. doi Growth rate dependent numbers of SeqA structures organize the multiple replication forks in rapidly growing Escherichia coli
    - Morigen
    Department of Cell Biology, Institute for Cancer Research, Norwegian Radium Hospital, Rikshospitalet, University of Oslo, 0310 Oslo, Norway
    Genes Cells 14:643-57. 2009
    ..The newly synthesized, hemimethylated DNA at each fork is bound by SeqA protein. The SeqA-DNA structures form distinct foci that can be observed by immunofluorescence microscopy...
  27. pmc Replication fork movement and methylation govern SeqA binding to the Escherichia coli chromosome
    Torsten Waldminghaus
    Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital and University of Oslo, 0310 Oslo, Norway
    Nucleic Acids Res 40:5465-76. 2012
    In Escherichia coli, the SeqA protein binds specifically to GATC sequences which are methylated on the A of the old strand but not on the new strand...
  28. pmc Regulation of sister chromosome cohesion by the replication fork tracking protein SeqA
    Mohan C Joshi
    Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
    PLoS Genet 9:e1003673. 2013
    ..coli is not currently understood. We report that the abundant fork tracking protein SeqA is a strong positive regulator of cohesion, and is responsible for markedly prolonged cohesion observed at "snap" ..
  29. pmc Replication fork inhibition in seqA mutants of Escherichia coli triggers replication fork breakage
    Ella Rotman
    Department of Microbiology, University of Illinois at Urbana Champaign, Urbana, IL, USA
    Mol Microbiol 93:50-64. 2014
    b>SeqA protein negatively regulates replication initiation in Escherichia coli and is also proposed to organize maturation and segregation of the newly replicated DNA...
  30. ncbi Interaction of SeqA and Dam methylase on the hemimethylated origin of Escherichia coli chromosomal DNA replication
    S Kang
    Institute for Molecular Biology and Genetics, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 274:11463-8. 1999
    Preferential binding of SeqA protein to hemimethylated oriC, the origin of Escherichia coli chromosomal replication, delays methylation by Dam methylase...
  31. ncbi A SeqA hyperstructure and its interactions direct the replication and sequestration of DNA
    V Norris
    Laboratoire des Processus Intégratifs Cellulaires, UPRES A CNRS 6037, IFR Systèmes Intégrés, Faculte des Sciences et Techniques, Universite de Rouen, F76821 Mont Saint Aignan Cedex, France
    Mol Microbiol 37:696-702. 2000
    ..In Escherichia coli, the formation of a SeqA hyperstructure via the phenomenon of local concentration may explain how the binding of SeqA to hemimethylated GATC ..
  32. ncbi The Escherichia coli SeqA protein binds specifically and co-operatively to two sites in hemimethylated and fully methylated oriC
    K Skarstad
    Department of Cell Biology, Institute for Cancer Research, Norway
    Mol Microbiol 36:1319-26. 2000
    The Escherichia coli SeqA protein has been found to affect initiation of replication negatively, both in vivo and in vitro. The mechanism of inhibition is, however, not known...
  33. ncbi Bidirectional migration of SeqA-bound hemimethylated DNA clusters and pairing of oriC copies in Escherichia coli
    S Hiraga
    Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University School of Medicine, Kumamoto 862 0976, Japan
    Genes Cells 5:327-41. 2000
    We previously found that SeqA protein, which binds preferentially to newly replicated hemimethylated DNA, is localized as discrete fluorescent foci in Escherichia coli cells...
  34. pmc The eclipse period of Escherichia coli
    U von Freiesleben
    Department of Microbiology, The Technical University of Denmark, Building 301, DK 2800 Lyngby, Denmark
    EMBO J 19:6240-8. 2000
    ..The SeqA protein was absolutely required for the eclipse, and DnaA titration studies suggested that the SeqA protein ..
  35. ncbi Mutual suppression of mukB and seqA phenotypes might arise from their opposing influences on the Escherichia coli nucleoid structure
    T Weitao
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, SE 751 24 Uppsala, Sweden
    Mol Microbiol 34:157-68. 1999
    A strain of Escherichia coli in which both the seqA and mukB genes were inactivated displayed partial suppressions of their individual phenotypes...
  36. pmc A case for sliding SeqA tracts at anchored replication forks during Escherichia coli chromosome replication and segregation
    T Brendler
    Gene Regulation and Chromosome Biology Laboratory, Division of Basic Sciences, NCI Frederick Cancer Research and Development Center, Frederick, MD 21702 1201, USA
    EMBO J 19:6249-58. 2000
    b>SeqA is an Escherichia coli DNA-binding protein that acts at replication origins and controls DNA replication. However, binding is not exclusive to origins...
  37. pmc Binding of SeqA protein to DNA requires interaction between two or more complexes bound to separate hemimethylated GATC sequences
    T Brendler
    ABL Basic Research Program, NCI Frederick Cancer Research and Development Center, Frederick, MD 21702 1201, USA
    EMBO J 18:2304-10. 1999
    The SeqA protein binds to the post-replicative forms of the origins of replication of the Escherichia coli chromosome (oriC) and the P1 plasmid (P1oriR) at hemimethylated GATC adenine methylation sites...
  38. pmc Effects of purified SeqA protein on oriC-dependent DNA replication in vitro
    S Wold
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    EMBO J 17:4158-65. 1998
    In vivo studies suggest that the Escherichia coli SeqA protein modulates replication initiation in two ways: by delaying initiation and by sequestering newly replicated origins from undergoing re-replication...
  39. pmc Coordinating DNA replication initiation with cell growth: differential roles for DnaA and SeqA proteins
    E Boye
    Department of Biophysics and Cell Biology, Institute for Cancer Research, Montebello, Oslo, Norway
    Proc Natl Acad Sci U S A 93:12206-11. 1996
    ..Furthermore, a comparison between wild-type and seqA mutant cells shows that initiation occurs at a 10-20% lower mass in the seqA mutant, providing direct evidence that ..
  40. ncbi SeqA: a negative modulator of replication initiation in E. coli
    M Lu
    Department of Biochemistry and Molecular Biology Harvard University, Cambridge, Massachusetts 02138
    Cell 77:413-26. 1994
    ..We report the identification of a gene required for sequestration and demonstrate that this gene, seqA, also serves as a negative modulator of the primary initiation process...
  41. ncbi SeqA limits DnaA activity in replication from oriC in Escherichia coli
    U von Freiesleben
    Department of Molecular Biology and Microbiology, Tufts University Medical School, Boston, Massachusetts 02111
    Mol Microbiol 14:763-72. 1994
    ..A similar mutation in this gene, named seqA1, has also been isolated. Here we show that the product of the seqA gene, SeqA, normally acts as an inhibitor of chromosomal initiation...
  42. pmc A protein that binds to the P1 origin core and the oriC 13mer region in a methylation-specific fashion is the product of the host seqA gene
    T Brendler
    Laboratory of Chromosome Biology, ABL Basic Research Program, NCI Frederick Cancer Research and Development Center, MD 21702 1201, USA
    EMBO J 14:4083-9. 1995
    ..It proved to be the product of the seqA gene that acts in the negative control of oriC by sequestration...
  43. ncbi Chromosome segregation control by Escherichia coli ObgE GTPase
    James J Foti
    Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454 9110, USA
    Mol Microbiol 65:569-81. 2007
    ..Localization of the SeqA DNA binding protein, normally seen as punctate foci, however, was disturbed...
  44. ncbi Cell cycle-dependent duplication and bidirectional migration of SeqA-associated DNA-protein complexes in E. coli
    S Hiraga
    Department of Molecular Cell Biology, Kumamoto University School of Medicine, Japan
    Mol Cell 1:381-7. 1998
    Using immunofluorescence microscopy, we have found that SeqA protein, a regulator of replication initiation, is localized as discrete fluorescent foci in E. coli wild-type cells...
  45. pmc Organization of sister origins and replisomes during multifork DNA replication in Escherichia coli
    Solveig Fossum
    Department of Cell Biology, Institute of Cancer Research, The Norwegian Radium Hospital, Oslo, Norway
    EMBO J 26:4514-22. 2007
    ..1-0.2 generations. The role of origin inactivation (sequestration) by the SeqA protein in origin colocalization was studied by comparing sequestration-deficient mutants with wild-type cells...
  46. ncbi E. coli SeqA protein binds oriC in two different methyl-modulated reactions appropriate to its roles in DNA replication initiation and origin sequestration
    S Slater
    Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts 02138, USA
    Cell 82:927-36. 1995
    The seqA gene negatively modulates replication initiation at the E. coli origin, oriC...
  47. ncbi Binding of SeqA protein to hemi-methylated GATC sequences enhances their interaction and aggregation properties
    Joo Seok Han
    School of Biological Sciences and Institute of Molecular Biology and Genetics, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 279:30236-43. 2004
    The SeqA protein regulates chromosome initiation and is involved in segregation in Escherichia coli. One SeqA protein binds to two hemi-methylated GATC sequences to form a stable SeqA-DNA complex...
  48. pmc Excess SeqA prolongs sequestration of oriC and delays nucleoid segregation and cell division
    Trond Bach
    Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, 0310 Oslo, Norway
    EMBO J 22:315-23. 2003
    ..The SeqA protein binds hemimethylated oriC in vitro...
  49. ncbi Identification of functional domains of the Escherichia coli SeqA protein
    Norie Fujikawa
    RIKEN Genomic Sciences Center, 1 7 22 Suehiro cho, Tsurumi, Yokohama 230 0045, Japan
    Biochem Biophys Res Commun 300:699-705. 2003
    The Escherichia coli SeqA protein, a negative regulator of chromosomal DNA replication, prevents the overinitiation of replication within one cell cycle by binding to hemimethylated G-mA-T-C sequences in the replication origin, oriC...
  50. ncbi SeqA protein aggregation is necessary for SeqA function
    H Lee
    Institute of Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Seoul 151 742, Korea
    J Biol Chem 276:34600-6. 2001
    The binding of SeqA protein to hemimethylated GATC sequences is important in the negative modulation of chromosomal initiation at oriC, and in the formation of SeqA foci necessary for Escherichia coli chromosome segregation...
  51. doi Modeling of the full-length Escherichia coli SeqA protein, in complex with DNA
    D Daghfous
    Laboratoire de Biochimie et de Biologie Moleculaire, Faculte des Sciences de Bizerte, 7021 Zarzouna, Tunisia
    Pathol Biol (Paris) 57:e61-6. 2009
    The Escherichia coli SeqA protein, a negative regulator of chromosome DNA replication, prevents the overinitiation of replication within one cell cycle by binding to hemimethylated GATC sequences in the replication origin, oriC...
  52. pmc Hda inactivation of DnaA is the predominant mechanism preventing hyperinitiation of Escherichia coli DNA replication
    Johanna E Camara
    Department of Biochemistry and Molecular Biology, Georgetown University Medical Center, Washington, District of Columbia 20007, USA
    EMBO Rep 6:736-41. 2005
    ..proposed: titration of free DnaA initiator protein by the datA locus, sequestration of newly replicated origins by SeqA protein and regulatory inactivation of DnaA (RIDA), in which active ATP-DnaA is converted to the inactive ADP-bound ..
  53. pmc Limiting DNA replication to once and only once
    E Boye
    Department of Cell Biology, Institute for Cancer Research, Montebello, Oslo, Norway
    EMBO Rep 1:479-83. 2000
    ..All cells have developed mechanisms for origin inactivation, but those of other bacteria and eukaryotic cells are clearly distinct from those of E. coli. Possible differences and similarities are discussed...
  54. ncbi Dynamic localization of bacterial and plasmid chromosomes
    S Hiraga
    Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kuhonji 4 24 1, Kumamoto 862 0976, Japan
    Annu Rev Genet 34:21-59. 2000
    ..coli, but not B. subtilis, the chromosomal DNA is fully methylated by DNA adenine methyltransferase. The E. coli SeqA protein, which binds preferentially to hemimethylated nascent DNA strands, exists as discrete foci in vivo...
  55. pmc New genes with old modus operandi. The connection between supercoiling and partitioning of DNA in Escherichia coli
    S DasGupta
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Centre, Sweden
    EMBO Rep 1:323-7. 2000
    ..daughter chromosomes are recondensed and moved apart through the concerted activities of topoisomerases and the SeqA (sequestration) and MukB (chromosome condensation) proteins, all of which modulate nucleoid superhelicity...
  56. ncbi Modulation of lambda plasmid and phage DNA replication by Escherichia coli SeqA protein
    Magdalena Narajczyk
    Department of Molecular Biology, University of Gdansk, 80 822 Gdansk, Poland
    Microbiology 153:1653-63. 2007
    b>SeqA protein, a main negative regulator of the replication initiation of the Escherichia coli chromosome, also has several other functions which are still poorly understood...
  57. ncbi Regulation of the initiation of chromosomal replication in bacteria
    Jolanta Zakrzewska-Czerwinska
    Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Wrocław, Poland
    FEMS Microbiol Rev 31:378-87. 2007
    ..This review summarizes recent research into the regulatory mechanisms of the initiation of chromosomal replication in bacteria, with emphasis on organisms other than E. coli...
  58. pmc Gene transcription and chromosome replication in Escherichia coli
    P Zhou
    Department of Biological Sciences, Florida Institute of Technology, Melbourne 32901, USA
    J Bacteriol 179:163-9. 1997
    ..Levels of transcripts from four of the genes, dam, nrdA, mukB, and seqA, were reduced at a certain stage during chromosome replication...
  59. ncbi Different localization of SeqA-bound nascent DNA clusters and MukF-MukE-MukB complex in Escherichia coli cells
    K Ohsumi
    Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kuhonji 4 24 1, Kumamoto 862 0976, Japan
    Mol Microbiol 40:835-45. 2001
    ..cells have two foci of mukB-gfpUV4 at one-quarter and three-quarter positions in the cell length and one focus of SeqA-bound nascent DNA at or near the middle of the cell...
  60. ncbi A novel cytoplasmic hemimethylated oriC binding activity
    J Garwood
    Biochemical Genetics Group, Institut Jacques Monod, Universite Paris, France
    J Biol Chem 271:7404-11. 1996
    ..The activity does not correspond to known hemimethylated binding proteins, although in the seqA deletion mutant, there is a 3-fold reduction of the activity...
  61. ncbi DNA replication defect in the Escherichia coli cgtA(ts) mutant arising from reduced DnaA levels
    Aleksandra E Sikora
    Department of Molecular Biology, University of Gdansk, Kładki 24, 80 822, Gdansk, Poland
    Arch Microbiol 185:340-7. 2006
    ..expression of dnaA were specific as analogous expression of another gene coding for a replication regulator, seqA, had no significant changes in growth and DNA synthesis in the cgtA mutant...
  62. pmc Reduced lipopolysaccharide phosphorylation in Escherichia coli lowers the elevated ori/ter ratio in seqA mutants
    Ella Rotman
    Department of Microbiology, University of Illinois, Urbana Champaign, IL, USA
    Mol Microbiol 72:1273-92. 2009
    The seqA defect in Escherichia coli increases the ori/ter ratio and causes chromosomal fragmentation, making seqA mutants dependent on recombinational repair (the seqA recA colethality)...
  63. pmc DnaAcos hyperinitiates by circumventing regulatory pathways that control the frequency of initiation in Escherichia coli
    Magdalena M Felczak
    Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824 1319, USA
    Mol Microbiol 72:1348-63. 2009
    ..or overcoming pathways that control initiation, respectively, we developed a genetic selection and identified seqA, datA, dnaN and hda, which function in pathways that either act at oriC or modulate DnaA activity...
  64. ncbi Hypothesis: hyperstructures regulate initiation in Escherichia coli and other bacteria
    Vic Norris
    Laboratoire des Processus Intégratifs Cellulaires, UPRESA CNRS 6037, Faculte des Sciences et Techniques, Universite de Rouen, 76821 Cedex, Mont Saint Aignan, France
    Biochimie 84:341-7. 2002
    ..directly involved in the cell cycle include initiation, replication and division hyperstructures based on DnaA, SeqA and the 2-minute cluster, respectively...
  65. ncbi Identification of mutator genes and mutational pathways in Escherichia coli using a multicopy cloning approach
    Hanjing Yang
    Department of Microbiology, Immunology and Molecular Genetics, and the Molecular Biology Institute, 1602 Molecular Sciences Building, 405 Hilgard Avenue, University of California, Los Angeles, CA 90095, USA
    Mol Microbiol 53:283-95. 2004
    ..MutS) and a primosomal component (DnaT), a negative modulator of initiation of replication/GATC-binding protein (SeqA), a stationary phase regulator AppY, a transcriptional regulator PaaX and three putative open reading frames, ycgW, ..
  66. ncbi Two types of localization of the DNA-binding proteins within the Escherichia coli nucleoid
    T A Azam
    Department of Molecular Genetics, National Institute of Genetics, Mishima, Shizuoka 411 8540, Japan
    Genes Cells 5:613-26. 2000
    ..The intracellular localization of these proteins in E. coli could be predicted from these data, but no attempt has been made thus far to directly observe the intracellular distribution of the DNA-binding proteins...
  67. ncbi Replication initiation. A new controller in Escherichia coli
    T A Baker
    Department of Biology, Massachusetts Institute of Technology, Cambridge 02139
    Curr Biol 4:945-6. 1994
    A new factor involved in the sequestration of recently active replication origins in Escherichia coli, SeqA, has been discovered and appears to be a multifaceted negative regulator of replication initiation.
  68. pmc Parental strand recognition of the DNA replication origin by the outer membrane in Escherichia coli
    J Herrick
    Institut Jacques Monod, CNRS, Universite Paris 7, France
    EMBO J 13:4695-703. 1994
    ..The purified LacZ-HobH fusion protein specifically binds oriC DNA at the same preferential sites as the membrane. A mutant of the hobH gene reveals partial asynchronous initiation of DNA replication...
  69. pmc Structural insights into the cooperative binding of SeqA to a tandem GATC repeat
    Yu Seon Chung
    Department of Biochemistry and Biomedical Sciences, Health Sciences Center, McMaster University, 1200 Main Street West, Hamilton, ON L8N 3Z5, Canada
    Nucleic Acids Res 37:3143-52. 2009
    b>SeqA is a negative regulator of DNA replication in Escherichia coli and related bacteria that functions by sequestering the origin of replication and facilitating its resetting after every initiation event...
  70. ncbi Competition between the replication initiator DnaA and the sequestration factor SeqA for binding to the hemimethylated chromosomal origin of E. coli in vitro
    A Taghbalout
    Institut Jacques Monod, CNRS, Université Paris 6 7, France
    Genes Cells 5:873-884. 2000
    ..oriC) in Escherichia coli enters a hemimethylated state at Dam methylation sites which are recognized by the SeqA protein. SeqA binds preferentially to hemimethylated GATC sequences of DNA in vitro...
  71. doi IHF- and SeqA-binding sites, present in plasmid cloning vectors, may significantly influence activities of promoters
    Robert Lyzeń
    Department of Molecular Biology, University of Gdansk, Kładki 24, 80 822 Gdansk, Poland
    Plasmid 60:125-30. 2008
    ..The IHF consensus sites are abundant and they can bind the IHF protein as shown in in vitro studies. The SeqA protein has a role in the complex regulation of pR activity, together with other factors altering DNA topology...
  72. pmc A role for nonessential domain II of initiator protein, DnaA, in replication control
    Kathryn L Molt
    Department of Biology and Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, Massachusetts 02454 9110, USA
    Genetics 183:39-49. 2009
    ..These suppressors suppressed the replication control defects of mutants in seqA alone and genetically mapped to the essential dnaA replication initiator gene...
  73. pmc A reduction in ribonucleotide reductase activity slows down the chromosome replication fork but does not change its localization
    Ingvild Odsbu
    Department of Cell Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway
    PLoS ONE 4:e7617. 2009
    ..Here we have investigated the effect of changes in ribonucleotide reductase (RNR) activity on chromosome replication and organization of replication forks in Escherichia coli...
  74. ncbi SeqA-mediated stimulation of a promoter activity by facilitating functions of a transcription activator
    Monika Słomińska
    Department of Molecular Biology, University of Gdansk, Kładki 24, 80 822 Gdansk, Poland
    Mol Microbiol 47:1669-79. 2003
    It was demonstrated recently that the SeqA protein, a main negative regulator of Escherichia coli chromosome replication initiation, is also a specific transcription factor...
  75. pmc Growth rate toxicity phenotypes and homeostatic supercoil control differentiate Escherichia coli from Salmonella enterica serovar Typhimurium
    Keith Champion
    Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
    J Bacteriol 189:5839-49. 2007
    ....
  76. ncbi Stimulation of the lambda pR promoter by Escherichia coli SeqA protein requires downstream GATC sequences and involves late stages of transcription initiation
    Robert Łyzeń
    Department of Molecular Biology, University of Gdansk, Kladki 24, 80 822 Gdansk, Poland
    Microbiology 152:2985-92. 2006
    Escherichia coli SeqA protein is a major negative regulator of chromosomal DNA replication acting by sequestration, and thus inactivation, of newly formed oriC regions...
  77. pmc High-affinity binding of hemimethylated oriC by Escherichia coli membranes is mediated by a multiprotein system that includes SeqA and a newly identified factor, SeqB
    N Shakibai
    Department of Microbiology, University of Connecticut Health Center, Farmington, CT 06032, USA
    Proc Natl Acad Sci U S A 95:11117-21. 1998
    ..in the prevention of premature reinitiation at newly replicated chromosomal origins in a reaction that involves the SeqA protein...
  78. ncbi Phospholipid changes in seqA and dam mutants of Escherichia coli
    Douraid Daghfous
    Laboratoire de Biochimie et de Biologie Moleculaire, Faculte des Sciences de Bizerte, 7021 Zarzouna, Tunisie
    C R Biol 329:271-6. 2006
    b>SeqA and Dam proteins were known to be responsible for regulating the initiation of replication and to affect the expression of many genes and metabolisms...
  79. pmc Null mutation of the dam or seqA gene suppresses temperature-sensitive lethality but not hypersensitivity to novobiocin of muk null mutants
    T Onogi
    Department of Molecular Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, Kumamoto 862 0976, Japan
    J Bacteriol 182:5898-901. 2000
    ..colony formation, anucleate cell production, chromosome cutting by septum closure, and abnormal localization of SeqA-DNA clusters. We show here that the associated muk null mutations cause hypersensitivity to novobiocin...
  80. ncbi The Escherichia coli SeqA protein binds specifically to two sites in fully and hemimethylated oriC and has the capacity to inhibit DNA replication and affect chromosome topology
    K Skarstad
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310, Oslo, Norway
    Biochimie 83:49-51. 2001
    The SeqA protein was identified as a factor that prevents reinitiation of newly replicated, hemimethylated origins...
  81. pmc Copy-number control of the Escherichia coli chromosome: a plasmidologist's view
    Kurt Nordström
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Centre, Box 596, S 751 24 Uppsala, Sweden
    EMBO Rep 7:484-9. 2006
    ..Superimposed on this basic mechanism are at least three systems that secure the synchronous initiation of multiple origins; however, these mechanisms are not essential for maintaining the copy number...
  82. ncbi Partitioning of the Escherichia coli chromosome: superhelicity and condensation
    K Nordstrom
    Department of Cell and Molecular Biology, Uppsala University, Biomedical Center, Box 596, 751 24, Uppsala, Sweden
    Biochimie 83:41-8. 2001
    ..E. coli strains, lacking mukB or seqA functions, are defective in segregation and cell division...
  83. ncbi Increased expression of a hemimethylated oriC binding protein, SeqA, in an aphA mutant
    M Kohiyama
    Biochimie Génétique, Institut Jacques Monod, CNRS Université Paris VII, France
    Biochimie 80:1043-6. 1998
    ..This sequestration is dependent on a hemimethylated oriC binding protein such as SeqA. We previously isolated a clone of phage lambda gt11 called hobH, producing a LacZ fusion protein which recognizes ..
  84. ncbi Hemi-methylated oriC DNA binding activity found in non-specific acid phosphatase
    E Reshetnyak
    Institut Jacques Monod, CNRS Université Paris 6 7, France
    Mol Microbiol 31:167-75. 1999
    ..Indirect immunofluorescene microscopy revealed the existence of discrete NAP foci at mid-cell in cells with two nucleoids, but at cell poles in those with one nucleoid...
  85. ncbi SeqA, the Escherichia coli origin sequestration protein, is also a specific transcription factor
    M Slominska
    Department of Molecular Biology, University of Gdansk, Kladki 24, 80 822 Gdansk, Poland
    Mol Microbiol 40:1371-9. 2001
    The SeqA protein is a negative regulator of initiation of DNA replication in the Escherichia coli chromosome. Here, we demonstrate that SeqA stimulates transcription from the bacteriophage lambda pR promoter both in vivo and in vitro...
  86. ncbi Dam-dependent phase variation of Ag43 in Escherichia coli is altered in a seqA mutant
    Jason Correnti
    202A Johnson Pavilion, Department of Microbiology, School of Medicine, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia 19104 6076, USA
    Mol Microbiol 44:521-32. 2002
    ..Hemimethylated agn43 DNA was also a binding substrate for the sequestration protein SeqA. Thus, SeqA, OxyR and Dam may compete for the same hemimethylated agn43 DNA that is formed after DNA replication in ..
  87. pmc Degradation of mutant initiator protein DnaA204 by proteases ClpP, ClpQ and Lon is prevented when DNA is SeqA-free
    Monika Slominska
    Department of Cell Biology, Institute for Cancer Research, Montebello, 0310 Oslo, Norway
    Biochem J 370:867-71. 2003
    ..The mutant DnaA protein is stabilized by the lack of SeqA protein. This stabilization was also observed in a dam mutant where the chromosome remains unmethylated...
  88. ncbi Expression of the seqA gene is negatively modulated by the HU protein in Escherichia coli
    H Lee
    Institute for Molecular Biology and Genetics, School of Biological Sciences, Seoul National University, Korea
    Mol Gen Genet 264:931-5. 2001
    The SeqA protein acts as a regulator of chromosomal replication initiation in Escherichia coli by sequestering hemi-methylated oriC, effectively blocking methylation and therefore preventing rapid re-initiation...
  89. ncbi Eclipse-synchrony relationship in Escherichia coli strains with mutations affecting sequestration, initiation of replication and superhelicity of the bacterial chromosome
    Jan A Olsson
    Department of Cell and Molecular Biology, Biomedical Centre, Uppsala University, Box 596, SE 751 24 Uppsala, Sweden
    J Mol Biol 334:919-31. 2003
    ..Sequestration is also believed to be responsible for initiation synchrony, since inactivation of either the seqA or the dam gene abolishes synchrony while drastically reducing the eclipse...

Research Grants1

  1. MECHANISMS OF ESCHERICHIA COLI CHROMOSOMAL REPLICATION
    JON KAGUNI; Fiscal Year: 2008
    ..Further study on the molecular mechanism of initiation and its regulation in E. coli should provide insight into the biochemistry of initiation and its control in other organisms. [unreadable] [unreadable]..