GONUTS has been updated to MW1.31 Most things seem to be working but be sure to report problems.

Have any questions? Please email us at ecoliwiki@gmail.com

PMID:20167799

From GONUTS
Jump to: navigation, search
Citation

Choi, W and Harshey, RM (2010) DNA repair by the cryptic endonuclease activity of Mu transposase. Proc. Natl. Acad. Sci. U.S.A. 107:10014-9

Abstract

Phage Mu transposes by two distinct pathways depending on the specific stage of its life cycle. A common strand transfer intermediate is resolved differentially in the two pathways. During lytic growth, the intermediate is resolved by replication of Mu initiated within the flanking target DNA; during integration of infecting Mu, it is resolved without replication, by removal and repair of DNA from a previous host that is still attached to the ends of the incoming Mu genome. We have discovered that the cryptic endonuclease activity reported for the isolated C-terminal domain of the transposase MuA [Wu Z, Chaconas G (1995) A novel DNA binding and nuclease activity in domain III of Mu transposase: Evidence for a catalytic region involved in donor cleavage. EMBO J 14:3835-3843], which is not observed in the full-length protein or in the assembled transpososome in vitro, is required in vivo for removal of the attached host DNA or "5'flap" after the infecting Mu genome has integrated into the E. coli chromosome. Efficient flap removal also requires the host protein ClpX, which is known to interact with the C-terminus of MuA to remodel the transpososome for replication. We hypothesize that ClpX constitutes part of a highly regulated mechanism that unmasks the cryptic nuclease activity of MuA specifically in the repair pathway.

Links

PubMed PMC2890431 Online version:10.1073/pnas.0912615107

Keywords

Adenosine Triphosphatases/metabolism; Amino Acid Sequence; Amino Acid Substitution; Bacteriophage mu/genetics; Bacteriophage mu/metabolism; Bacteriophage mu/physiology; DNA Repair/physiology; DNA Replication/physiology; Endonucleases/chemistry; Endonucleases/genetics; Endonucleases/metabolism; Endopeptidase Clp/metabolism; Escherichia coli K12/genetics; Escherichia coli K12/physiology; Escherichia coli K12/virology; Escherichia coli Proteins/metabolism; Lysogeny; Models, Biological; Molecular Chaperones/metabolism; Mutagenesis, Site-Directed; Protein Structure, Tertiary; Recombinant Proteins/chemistry; Recombinant Proteins/genetics; Recombinant Proteins/metabolism; Transposases/chemistry; Transposases/genetics; Transposases/metabolism; Virus Integration/physiology; Virus Replication/physiology

Significance

Annotations

Gene product Qualifier GO Term Evidence Code with/from Aspect Extension Notes Status

BPMU:TRA

enables

GO:1990238: double-stranded DNA endodeoxyribonuclease activity

ECO:0000315: mutant phenotype evidence used in manual assertion

F

Seeded From UniProt

complete

BPMU:TNPA

GO:1990238: double-stranded DNA endodeoxyribonuclease activity

ECO:0000315:

F

WT MuA shows endonuclease activity on pUC19 in OC and SC forms, while domain III defective mutants failed to degrade the plasmid (Figure 2B).

complete
CACAO 10907

BPMU:TNPA

enables

GO:1990238: double-stranded DNA endodeoxyribonuclease activity

ECO:0000315: mutant phenotype evidence used in manual assertion

F

Seeded From UniProt

complete

Notes

See also

References

See Help:References for how to manage references in GONUTS.