Cell cycle-dependent duplication and bidirectional migration of SeqA-associated DNA-protein complexes in E. coli.

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. Surprisingly, SeqA foci were observed also in an oriC deletion mutant. Statistical analysis revealed that a SeqA focus is localized at midcell in newborn cells. The SeqA focus is duplicated and tethered at midcell until an FtsZ ring is formed. Subsequently, these foci migrate in opposite directions toward cell quarter sites and remain tethered there until the cell divides. The cell cycle-dependent bidirectional migration of SeqA-DNA complexes is quite different from the migration pattern of oriC Dna copies. MukB protein is required for correct localization of SeqA complexes by an unknown mechanism.

[1]  M. Schaechter,et al.  SeqA limits DnaA activity in replication from oriC in Escherichia coli , 1994, Molecular microbiology.

[2]  W. Messer,et al.  Effect of dam methylation on the activity of the E. coli replication origin, oriC. , 1985, The EMBO journal.

[3]  M. Yanagida,et al.  Telomere-led premeiotic chromosome movement in fission yeast. , 1994, Science.

[4]  J. Errington,et al.  Direct evidence for active segregation of oriC regions of the Bacillus subtilis chromosome and co‐localization with the Spo0J partitioning protein , 1997, Molecular microbiology.

[5]  T. Stokke,et al.  Coordinating DNA replication initiation with cell growth: differential roles for DnaA and SeqA proteins. , 1996, Proceedings of the National Academy of Sciences of the United States of America.

[6]  H. Steen,et al.  Timing of initiation of chromosome replication in individual Escherichia coli cells. , 1986, The EMBO journal.

[7]  O. Fayet,et al.  Multiple origin usage for DNA replication in sdrA(rnh) mutants of Escherichia coli K-12. Initiation in the absence of oriC. , 1984, Journal of molecular biology.

[8]  K. Skarstad,et al.  Timing of chromosomal replication in Escherichia coli. , 1988, Biochimica et biophysica acta.

[9]  Moselio Schaechter,et al.  The replicative origin of the E. coli chromosome binds to cell membranes only when hemimethylated , 1988, Cell.

[10]  D. W. Smith,et al.  Methylation of GATC sites is required for precise timing between rounds of DNA replication in Escherichia coli , 1989, Journal of bacteriology.

[11]  J. Garwood,et al.  Co‐ordination between membrane oriC sequestration factors and a chromosome partitioning protein, TolC (MukA) , 1996, Molecular microbiology.

[12]  K. Isono,et al.  The physical map of the whole E. coli chromosome: Application of a new strategy for rapid analysis and sorting of a large genomic library , 1987, Cell.

[13]  T. Ogura,et al.  Chromosome partitioning in Escherichia coli: novel mutants producing anucleate cells , 1989, Journal of bacteriology.

[14]  A. Grossman,et al.  Bipolar Localization of the Replication Origin Regions of Chromosomes in Vegetative and Sporulating Cells of B. subtilis , 1997, Cell.

[15]  T. Ogura,et al.  Carboxyl terminal region of the MukB protein in Escherichia coli is essential for DNA binding activity , 1996 .

[16]  N. Kleckner,et al.  E. coli oriC and the dnaA gene promoter are sequestered from dam methyltransferase following the passage of the chromosomal replication fork , 1990, Cell.

[17]  T. Ogura,et al.  E.coli MukB protein involved in chromosome partition forms a homodimer with a rod‐and‐hinge structure having DNA binding and ATP/GTP binding activities. , 1992, The EMBO journal.

[18]  F. Hansen,et al.  THE ORIGIN OF REPLICATION, oriC, OF THE ESCHERICHIA COLI CHROMOSOME: GENES NEAR oriC AND CONSTRUCTION OF oriC DELETION MUTATIONS , 1980 .

[19]  J. Errington,et al.  Dynamic, mitotic-like behavior of a bacterial protein required for accurate chromosome partitioning. , 1997, Genes & development.

[20]  D. Russell,et al.  Hemimethylation prevents DNA replication in E. coli , 1987, Cell.

[21]  S. Wickner,et al.  Genetics and enzymology of DNA replication in Escherichia coli. , 1992, Annual review of genetics.

[22]  A. Løbner-Olesen,et al.  Chromosome partitioning in Escherichia coli , 1992, Journal of bacteriology.

[23]  T. Yura,et al.  Requirement of the Escherichia coli dnaA gene function for ori-2-dependent mini-F plasmid replication , 1987, Journal of bacteriology.

[24]  S. Hiraga Chromosome and plasmid partition in Escherichia coli. , 1992, Annual review of biochemistry.

[25]  T. Ogura,et al.  The new gene mukB codes for a 177 kd protein with coiled‐coil domains involved in chromosome partitioning of E. coli. , 1991, The EMBO journal.

[26]  A. Landoulsi,et al.  The E. coli cell surface specifically prevents the initiation of DNA replication at oriC on heminethylated DNA templates , 1990, Cell.

[27]  T. Ogura,et al.  Mutants defective in chromosome partitioning in E. coli. , 1991, Research in microbiology.

[28]  Douglas W. Smith,et al.  The bacterial origin of replication, oriC , 1986, Cell.

[29]  E. Bi,et al.  FtsZ ring formation in fts mutants , 1996, Journal of bacteriology.

[30]  K. Skarstad,et al.  The DnaA protein determines the initiation mass of Escherichia coli K-12 , 1989, Cell.

[31]  A. Grossman,et al.  Bipolar localization of a chromosome partition protein in Bacillus subtilis. , 1997, Proceedings of the National Academy of Sciences of the United States of America.

[32]  A. Murray,et al.  Chromosome and Low Copy Plasmid Segregation in E. coli: Visual Evidence for Distinct Mechanisms , 1997, Cell.

[33]  E. Boye,et al.  The role of dam methyltransferase in the control of DNA replication in E. coli , 1990, Cell.

[34]  K. Skarstad,et al.  E. coli SeqA protein binds oriC in two different methyl-modulated reactions appropriate to its roles in DNA replication initiation and origin sequestration , 1995, Cell.

[35]  B. Haarer,et al.  Immunofluorescence methods for yeast. , 1991, Methods in enzymology.

[36]  Nancy Kleckner,et al.  SeqA: A negative modulator of replication initiation in E. coli , 1994, Cell.

[37]  S. Cooper,et al.  On the bacterial life sequence. , 1968, Cold Spring Harbor symposia on quantitative biology.

[38]  J. Gober,et al.  Cell Cycle–Dependent Polar Localization of Chromosome Partitioning Proteins in Caulobacter crescentus , 1997, Cell.

[39]  H. Niki,et al.  Subcellular Distribution of Actively Partitioning F Plasmid during the Cell Division Cycle in E. coli , 1997, Cell.