Tus (biology)

Tus is a sequence-specific DNA-binding protein that promotes termination in the DNA replication process of prokaryotes. In E Coli, Tus binds to 10 closely related sites encoded in the chromosome. These sites bind 23 base-pairs. The 10 sites are called Ter sites, and are designated TerA, TerB, ..., TerJ. These binding sites are asymmetric, such that when a Tus-Ter complex (Tus protein bound to a Ter site) is encountered by a replication fork from one direction, the complex is dissociated and replication continues (permissive). But when encountered from the other direction, the Tus-Ter complex provides a much larger kinetic barrier and halts replication (non-permissive). The multiple Ter sites in the chromosome are oriented such that the two oppositely moving replication forks are both stalled in the desired termination region.[2]

Further reading

References

  1. ^ a b Kamada, K.; Horiuchi, T.; Ohsumi, K.; Shimamoto, N.; Morikawa, K. (1996). "Structure of a replication-terminator protein complexed with DNA". Nature 383 (6601): 598–603. Bibcode 1996Natur.383..598K. doi:10.1038/383598a0. PMID 8857533.  edit
  2. ^ a b Mulcair, M.; Schaeffer, P.; Oakley, A.; Cross, H.; Neylon, C.; Hill, T.; Dixon, N. (2006). "A Molecular Mousetrap Determines Polarity of Termination of DNA Replication in E. Coli". Cell 125 (7): 1309–1319. doi:10.1016/j.cell.2006.04.040. PMID 16814717.  edit
  3. ^ Neylon; Brown, S. E.; Kralicek, A. V.; Miles, C. S.; Love, C. A.; Dixon, N. E. (2000). "Interaction of the Escherichia coli replication terminator protein (Tus) with DNA: a model derived from DNA-binding studies of mutant proteins by surface plasmon resonance". Biochemistry 39 (39): 11989–11999. doi:10.1021/bi001174w. PMID 11009613.  edit
  4. ^ Neylon, C.; Kralicek, A. V.; Hill, T. M.; Dixon, N. E. (2005). "Replication Termination in Escherichia coli: Structure and Antihelicase Activity of the Tus-Ter Complex". Microbiology and Molecular Biology Reviews 69 (3): 501. doi:10.1128/MMBR.69.3.501-526.2005. PMC 1197808. PMID 16148308. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1197808.  edit
  5. ^ Skokotas; Wrobleski, M.; Hill, T. M. (1994). "Isolation and characterization of mutants of Tus, the replication arrest protein of Escherichia coli". The Journal of biological chemistry 269 (32): 20446–20455. PMID 8051142.  edit
  6. ^ Coskun-ari; Skokotas, A.; Moe, G. R.; Hill, T. M. (1994). "Biophysical characteristics of Tus, the replication arrest protein of Escherichia coli". The Journal of biological chemistry 269 (6): 4027–4034. PMID 8307958.  edit