Bacterial DNA segregation dynamics mediated by the polymerizing protein ParF

Barillà, Daniela; Rosenberg, Mark F.; Nobbmann, Ulf; Hayes, Finbarr

doi:10.1038/sj.emboj.7600619

Cited by 129 publications

(226 citation statements)

References 42 publications

(89 reference statements)

Supporting

Mentioning

208

Contrasting

Order By: Relevance

“…2B and Fig. S1) (12,17,33,34). The hydrolytic activity of ParA2 was enhanced in the presence of DNA and ParB2 (Fig.…”

Section: Para2 Does Not Form Higher Molecular Weight Structures In Thementioning

confidence: 99%

“…Several of these proteins have been shown to form dynamic filamentous structures in vivo and/or ATPdependent filaments in vitro (9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). The best example of how a Par ATPase can drive the partitioning process is provided by studies of ParM, the type II ATPase of plasmid R1.…”

mentioning

confidence: 99%

“…Furthermore, the structures of ParA filaments differ from their type II counterparts, suggesting that type I par systems rely on distinct mechanisms to mediate segregation. Several ParA homologs-including SopA of F (Ia), ParF of pTP228 (Ib), and ParA of pB171 (Ib)-form bundled filaments with one frayed end when incubated with ATP, leading to speculation that filament polarity is important for function (12,16,17).…”

mentioning

confidence: 99%

See 2 more Smart Citations

ParA2, aVibrio choleraechromosome partitioning protein, forms left-handed helical filaments on DNA

Hui

Galkin²,

Xiong³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Most bacterial chromosomes contain homologs of plasmid partitioning (par) loci. These loci encode ATPases called ParA that are thought to contribute to the mechanical force required for chromosome and plasmid segregation. In Vibrio cholerae, the chromosome II (chrII) par locus is essential for chrII segregation. Here, we found that purified ParA2 had ATPase activities comparable to other ParA homologs, but, unlike many other ParA homologs, did not form high molecular weight complexes in the presence of ATP alone. Instead, formation of high molecular weight ParA2 polymers required DNA. Electron microscopy and three-dimensional reconstruction revealed that ParA2 formed bipolar helical filaments on double-stranded DNA in a sequence-independent manner. These filaments had a distinct change in pitch when ParA2 was polymerized in the presence of ATP versus in the absence of a nucleotide cofactor. Fitting a crystal structure of a ParA protein into our filament reconstruction showed how a dimer of ParA2 binds the DNA. The filaments formed with ATP are left-handed, but surprisingly these filaments exert no topological changes on the right-handed B-DNA to which they are bound. The stoichiometry of binding is one dimer for every eight base pairs, and this determines the geometry of the ParA2 filaments with 4.4 dimers per 120 Å pitch left-handed turn. Our findings will be critical for understanding how ParA proteins function in plasmid and chromosome segregation.nucleoprotein filament | DNA segregation

show abstract

“…2B and Fig. S1) (12,17,33,34). The hydrolytic activity of ParA2 was enhanced in the presence of DNA and ParB2 (Fig.…”

Section: Para2 Does Not Form Higher Molecular Weight Structures In Thementioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

ParA2, aVibrio choleraechromosome partitioning protein, forms left-handed helical filaments on DNA

Hui

Galkin²,

Xiong³

et al. 2010

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

show abstract

“…The DLS method is generally used to determine the size distribution of small particles dispersed in solution and is often applied to protein complexes (Schmitz, 1990;Barilla et al, 2005; Tönges et al, 2006). We employed DLS analysis to determine the hydrodynamic diameter, or size, of multimers formed by the NTD, ID and N63K.…”

Section: Dls Analysismentioning

confidence: 99%

Domain organization of the N-terminal portion of hordeivirus movement protein TGBp1

Makarov

Rybakova

Ефимов

et al. 2009

Journal of General Virology

View full text Add to dashboard Cite

Three 'triple gene block' proteins known as TGBp1, TGBp2 and TGBp3 are required for cell-tocell movement of plant viruses belonging to a number of genera including Hordeivirus. Hordeiviral TGBp1 interacts with viral genomic RNAs to form ribonucleoprotein (RNP) complexes competent for translocation between cells through plasmodesmata and over long distances via the phloem. Binding of hordeivirus TGBp1 to RNA involves two protein regions, the C-terminal NTPase/ helicase domain and the N-terminal extension region. This study demonstrated that the extension region of hordeivirus TGBp1 consists of two structurally and functionally distinct domains called the N-terminal domain (NTD) and the internal domain (ID). In agreement with secondary structure predictions, analysis of circular dichroism spectra of the isolated NTD and ID demonstrated that the NTD represents a natively unfolded protein domain, whereas the ID has a pronounced secondary structure. Both the NTD and ID were able to bind ssRNA non-specifically. However, whilst the NTD interacted with ssRNA non-cooperatively, the ID bound ssRNA in a cooperative manner. Additionally, both domains bound dsRNA. The NTD and ID formed low-molecular-mass oligomers, whereas the ID also gave rise to high-molecular-mass complexes. The isolated ID was able to interact with both the NTD and the C-terminal NTPase/helicase domain in solution. These data demonstrate that the hordeivirus TGBp1 has three RNA-binding domains and that interaction between these structural units can provide a basis for remodelling of viral RNP complexes at different steps of cell-to-cell and long-distance transport of virus infection. INTRODUCTIONTransport of plant viruses from cell to cell occurs through plasmodesmata and requires virus-encoded movement proteins (Boevink & Oparka, 2005;Lucas, 2006;Epel, 2009). In the genus Hordeivirus, viral movement proteins are represented by three proteins encoded by a 'triple gene block' (TGB) and referred to as TGBp1, TGBp2 and TGBp3 (Solovyev et al., 1996). The TGB is a conserved module of overlapping genes found in a number of virus groups (Morozov & Solovyev, 2003). Hordeivirus TGBp1 binds viral genomic RNA forming a cell-to-cell transportcompetent complex (Brakke et al., 1988;Kalinina et al., 2001;Lim et al., 2008;Jackson et al., 2009). TGBp2 and TGBp3 are small membrane proteins necessary for intracellular transport of complexes containing TGBp1 and viral RNA to plasmodesmata (Morozov & Solovyev, 2003;Zamyatnin et al., 2004; Haupt et al., 2005;Jackson et al., 2009 Lim et al., 2008;Jackson et al., 2009). Such TGBp1-RNA complexes are considered to be a form of viral genome capable of cell-to-cell and long-distance transport in plants (Morozov & Solovyev, 2003;Lim et al., 2008). In potex-like TGBs, the whole TGBp1 sequence is represented by the NTPase/helicase domain (HELD) with seven conserved motifs of the superfamily 1 NTPases/helicases (Gorbalenya et al., 1989), whereas the hordei-like TGBp1 has an additional N-terminal 'extension region' (Morozov & Solovyev, ...

show abstract

“…In the ATP-bound form, they specifically interact with cognate partition complexes through contact with ParB proteins. The ATP-bound form of type I ParAs spontaneously forms polymers, which appear as bundled filaments in electron micrographs (12,(17)(18)(19). The role of these filaments is not understood but they could be related to the rapid movement of partition complexes in the cell.…”

mentioning

confidence: 99%

Dual Role of DNA in Regulating ATP Hydrolysis by the SopA Partition Protein

Ah-Seng

Lopez

Pasta

et al. 2009

Journal of Biological Chemistry

View full text Add to dashboard Cite

In bacteria, mitotic stability of plasmids and many chromosomes depends on replicon-specific systems, which comprise a centromere, a centromere-binding protein and an ATPase. Dynamic self-assembly of the ATPase appears to enable active partition of replicon copies into cell-halves, but for Walker-box partition ATPases the molecular mechanism is unknown. ATPase activity appears to be essential for this process. DNA and centromere-binding proteins are known to stimulate the ATPase activity but molecular details of the stimulation mechanism have not been reported. We have investigated the interactions which stimulate ATP hydrolysis by the SopA partition ATPase of plasmid F. By using SopA and SopB proteins deficient in DNA binding, we have found that the intrinsic ability of SopA to hydrolyze ATP requires direct DNA binding by SopA but not by SopB. Our results show that two independent interactions of SopA act in synergy to stimulate its ATPase. SopA must interact with (i) DNA, through its ATP-dependent nonspecific DNA binding domain and (ii) SopB, which we show here to provide an arginine-finger motif. In addition, the latter interaction stimulates ATPase maximally when SopB is part of the partition complex. Hence, our data demonstrate that DNA acts on SopA in two ways, directly as nonspecific DNA and through SopB as centromeric DNA, to fully activate SopA ATP hydrolysis.

show abstract

Bacterial DNA segregation dynamics mediated by the polymerizing protein ParF

Cited by 129 publications

References 42 publications

ParA2, aVibrio choleraechromosome partitioning protein, forms left-handed helical filaments on DNA

ParA2, aVibrio choleraechromosome partitioning protein, forms left-handed helical filaments on DNA

Domain organization of the N-terminal portion of hordeivirus movement protein TGBp1

Dual Role of DNA in Regulating ATP Hydrolysis by the SopA Partition Protein

Contact Info

Product

Resources

About