Archaeology of Eukaryotic DNA Replication

Makarova, Kira S.; Koonin, Eugene V.

doi:10.1101/cshperspect.a012963

Cited by 72 publications

(73 citation statements)

References 115 publications

(155 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The replisome composition is dynamic; some components involved in lagging-strand synthesis only transiently associate with the replisome, whereas others require long-lived stable interactions for activity (1)(2)(3). Although sequence conservation and homology modeling have identified many components of the archaeal replisome, archaeon-specific replication factors have also been isolated from complexes formed with established components of the replication machinery (4)(5)(6)(7)(8)(9)(10). One such factor, encoded by TK1252 in Thermococcus kodakarensis and designated GAN (GINS-associated nuclease), shares sequence and structural similarities with the bacterial RecJ and eukaryotic Cdc45 proteins (11,12).…”

mentioning

confidence: 99%

The GAN Exonuclease or the Flap Endonuclease Fen1 and RNase HII Are Necessary for Viability of Thermococcus kodakarensis

et al. 2017

View full text Add to dashboard Cite

Many aspects of and factors required for DNA replication are conserved across all three domains of life, but there are some significant differences surrounding lagging-strand synthesis. In Archaea, a 5=-to-3= exonuclease, related to both bacterial RecJ and eukaryotic Cdc45, that associates with the replisome specifically through interactions with GINS was identified and designated GAN (for GINS-associated nuclease). Despite the presence of a well-characterized flap endonuclease (Fen1), it was hypothesized that GAN might participate in primer removal during Okazaki fragment maturation, and as a Cdc45 homologue, GAN might also be a structural component of an archaeal CMG (Cdc45, MCM, and GINS) replication complex. We demonstrate here that, individually, either Fen1 or GAN can be deleted, with no discernible effects on viability and growth. However, deletion of both Fen1 and GAN was not possible, consistent with both enzymes catalyzing the same step in primer removal from Okazaki fragments in vivo. RNase HII has also been proposed to participate in primer processing during Okazaki fragment maturation. Strains with both Fen1 and RNase HII deleted grew well. GAN activity is therefore sufficient for viability in the absence of both RNase HII and Fen1, but it was not possible to construct a strain with both RNase HII and GAN deleted. Fen1 alone is therefore insufficient for viability in the absence of both RNase HII and GAN. The ability to delete GAN demonstrates that GAN is not required for the activation or stability of the archaeal MCM replicative helicase. IMPORTANCEThe mechanisms used to remove primer sequences from Okazaki fragments during lagging-strand DNA replication differ in the biological domains. Bacteria use the exonuclease activity of DNA polymerase I, whereas eukaryotes and archaea encode a flap endonuclease (Fen1) that cleaves displaced primer sequences. RNase HII and the GINS-associated exonuclease GAN have also been hypothesized to assist in primer removal in Archaea. Here we demonstrate that in Thermococcus kodakarensis, either Fen1 or GAN activity is sufficient for viability. Furthermore, GAN can support growth in the absence of both Fen1 and RNase HII, but Fen1 and RNase HII are required for viability in the absence of GAN.KEYWORDS Archaea, CMG complex, DNA replication, GINS-associated nuclease GAN, Okazaki fragment, RNase HII, flap endonuclease Fen1 D NA replication is catalyzed by a protein complex, designated the replisome, with structural and catalytic components tightly regulated, intertwined, and coordinated to facilitate both leading-and lagging-strand synthesis. The replisome composition is

show abstract

mentioning

confidence: 99%

The GAN Exonuclease or the Flap Endonuclease Fen1 and RNase HII Are Necessary for Viability of Thermococcus kodakarensis

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In archaea, which like many bacteria have small circular genomes, there are some species, such as the Crenarchaeota Sulfolobus solfataricus, with multiple origins that are used during normal cell division cycles (Bell 2012). How origin-firing events are coordinated in archaea is not known, but interestingly homologs of CDK and DDK are present in most archaeal lineages (Makarova and Koonin 2013). Further studies on replication initiation control across all the domains of life will be important to understand the multiple mechanisms that have evolved to guarantee the perfect duplication and inheritance of the genome.…”

Section: Discussionmentioning

confidence: 99%

Evolutionary conservation of the CDK targets in eukaryotic DNA replication initiation

Zegerman

2015

Chromosoma

View full text Add to dashboard Cite

A fundamental requirement for all organisms is the faithful duplication and transmission of the genetic material. Failure to accurately copy and segregate the genome during cell division leads to loss of genetic information and chromosomal abnormalities. Such genome instability is the hallmark of the earliest stages of tumour formation. Cyclin-dependent kinase (CDK) plays a vital role in regulating the duplication of the genome within the eukaryotic cell cycle. Importantly, this kinase is deregulated in many cancer types and is an emerging target of chemotherapeutics. In this review, I will consider recent advances concerning the role of CDK in replication initiation across eukaryotes. The implications for strict CDK-dependent regulation of genome duplication in the context of the cell cycle will be discussed.

show abstract

“…16 In particular, identification of the CMG complex consisting of Cdc45, Mcm2-7, and GINS as an active DNA helicase [17][18] leads to a common belief that the basic mechanism for the activation of pre-RC is conserved in eukaryotes. However, limited conservations of yeast initiator proteins such as Sld2, Sld3, and Dpb11 with metazoan RecQ4, Treslin, and TopBP1, respectively, suggest that there might be some additional and/or distinct roles for these metazoan replication initiators.…”

Section: Introductionmentioning

confidence: 99%

RecQ4 promotes the conversion of the pre-initiation complex at a site-specific origin for DNA unwinding inXenopusegg extracts

et al. 2015

View full text Add to dashboard Cite

Eukaryotic DNA replication is initiated through stepwise assembly of evolutionarily conserved replication proteins onto replication origins, but how the origin DNA is unwound during the assembly process remains elusive. Here, we established a site-specific origin on a plasmid DNA, using in vitro replication systems derived from Xenopus egg extracts. We found that the pre-replicative complex (pre-RC) was preferentially assembled in the vicinity of GAL4 DNA-binding sites of the plasmid, depending on the binding of Cdc6 fused with a GAL4 DNA-binding domain in Cdc6-depleted extracts. Subsequent addition of nucleoplasmic S-phase extracts to the GAL4-dependent pre-RC promoted initiation of DNA replication from the origin, and components of the pre-initiation complex (pre-IC) and the replisome were recruited to the origin concomitant with origin unwinding. In this replication system, RecQ4 is dispensable for both recruitment of Cdc45 onto the origin and stable binding of Cdc45 and GINS to the pre-RC assembled plasmid. However, both origin binding of DNA polymerase a and unwinding of DNA were diminished upon depletion of RecQ4 from the extracts. These results suggest that RecQ4 plays an important role in the conversion of pre-ICs into active replisomes requiring the unwinding of origin DNA in vertebrates.

show abstract

Archaeology of Eukaryotic DNA Replication

Cited by 72 publications

References 115 publications

The GAN Exonuclease or the Flap Endonuclease Fen1 and RNase HII Are Necessary for Viability of Thermococcus kodakarensis

The GAN Exonuclease or the Flap Endonuclease Fen1 and RNase HII Are Necessary for Viability of Thermococcus kodakarensis

Evolutionary conservation of the CDK targets in eukaryotic DNA replication initiation

RecQ4 promotes the conversion of the pre-initiation complex at a site-specific origin for DNA unwinding inXenopusegg extracts

Contact Info

Product

Resources

About