Orc
Mostrando 13-24 de 131 artigos, teses e dissertações.
-
13. Xenopus origin recognition complex (ORC) initiates DNA replication preferentially at sequences targeted by Schizosaccharomyces pombe ORC
Budding yeast (Saccharomyces cerevisiae) origin recognition complex (ORC) requires ATP to bind specific DNA sequences, whereas fission yeast (Schizosaccharomyces pombe) ORC binds to specific, asymmetric A:T-rich sites within replication origins, independently of ATP, and frog (Xenopus laevis) ORC seems to bind DNA non-specifically. Here we show that despite
Oxford University Press.
-
14. Functional analysis of mutant and wild-type Drosophila origin recognition complex
The origin recognition complex (ORC) is the DNA replication initiator protein in eukaryotes. We have reconstituted a functional recombinant Drosophila ORC and compared activities of the wild-type and several mutant ORC variants. Drosophila ORC is an ATPase, and our studies show that the ORC1 subunit is essential for ATP hydrolysis and for ATP-dependent DNA b
The National Academy of Sciences.
-
15. The origin recognition complex in silencing, cell cycle progression, and DNA replication.
This report describes the isolation of ORC5, the gene encoding the fifth largest subunit of the origin recognition complex, and the properties of mutants with a defective allele of ORC5. The orc5-1 mutation caused temperature-sensitive growth and, at the restrictive temperature, caused cell cycle arrest. At the permissive temperature, the orc5-1 mutation cau
-
16. Atomic force microscopic analysis of the binding of the Schizosaccharomyces pombe origin recognition complex and the spOrc4 protein with origin DNA
In eukaryotes, the initiation of DNA replication requires the interaction between origin sequences and the origin recognition complex (ORC), which is highly conserved. In this report, atomic force microscopy (AFM) was used to examine the binding of Schizosaccharomyces pombe (sp) ORC and the spOrc4 protein with the sp autonomously replicating sequence 1 (ars1
National Academy of Sciences.
-
17. Genetic Interaction of an Origin Recognition Complex Subunit and the Polycomb Group Gene MEDEA during Seed DevelopmentW⃞
The eukaryotic origin recognition complex (ORC) is made up of six subunits and functions in nuclear DNA replication, chromatin structure, and gene silencing in both fungi and metazoans. We demonstrate that disruption of a plant ORC subunit homolog, AtORC2 of Arabidopsis (Arabidopsis thaliana), causes a zygotic lethal mutant phenotype (orc2). Seeds of orc2 ab
American Society of Plant Biologists.
-
18. The Schizosaccharomyces pombe origin recognition complex interacts with multiple AT-rich regions of the replication origin DNA by means of the AT-hook domains of the spOrc4 protein
The interaction between an origin sequence and the origin recognition complex (ORC), which is highly conserved in eukaryotes, is critical for the initiation of DNA replication. In this report, we have examined the interaction between the Schizosaccharomyces pombe (sp) autonomously replicating sequence 1 (ars1) and the spORC. For this purpose, we have purifie
The National Academy of Sciences.
-
19. Site-Specific DNA Binding of the Schizosaccharomyces pombe Origin Recognition Complex Is Determined by the Orc4 Subunit
The mechanism by which origin recognition complexes (ORCs) identify replication origins was investigated using purified Orc proteins from Schizosaccharomyces pombe. Orc4p alone bound tightly and specifically to several sites within S. pombe replication origins that are genetically required for origin activity. These sites consisted of clusters of A or T resi
American Society for Microbiology.
-
20. Identification and reconstitution of the origin recognition complex from Schizosaccharomyces pombe
The origin recognition complex (ORC), first identified in Saccharomyces cerevisiae (sc), is a six-subunit protein complex that binds to DNA origins. Here, we report the identification and cloning of cDNAs encoding the six subunits of the ORC of Schizosaccharomyces pombe (sp). Sequence analyses revealed that spOrc1, 2, and 5 subunits are highly conserved comp
The National Academy of Sciences.
-
21. Role for Cdk1 (Cdc2)/Cyclin A in Preventing the Mammalian Origin Recognition Complex's Largest Subunit (Orc1) from Binding to Chromatin during Mitosis
The eukaryotic origin recognition complex (ORC) selects the genomic sites where prereplication complexes are assembled and DNA replication begins. In proliferating mammalian cells, ORC activity appears to be regulated by reducing the affinity of the Orc1 subunit for chromatin during S phase and then preventing reformation of a stable ORC-chromatin complex un
American Society for Microbiology.
-
22. Differential DNA affinity specifies roles for the origin recognition complex in budding yeast heterochromatin
The origin recognition complex (ORC) marks chromosomal positions as replication origins and is essential for replication initiation. At a few loci, the ORC functions in heterochromatin formation. We show that the ORC's two roles at the heterochromatic HMRa locus in Saccharomyces cerevisiae were regulated by differences in the ORC's interaction with its
Cold Spring Harbor Laboratory Press.
-
23. DNA topology, not DNA sequence, is a critical determinant for Drosophila ORC–DNA binding
Drosophila origin recognition complex (ORC) localizes to defined positions on chromosomes, and in follicle cells the chorion gene amplification loci are well-studied examples. However, the mechanism of specific localization is not known. We have studied the DNA binding of DmORC to investigate the cis-requirements for DmORC:DNA interaction. DmORC displays at
Nature Publishing Group.
-
24. Mammalian Orc1 Protein Is Selectively Released from Chromatin and Ubiquitinated during the S-to-M Transition in the Cell Division Cycle
Previous studies have shown that changes in the affinity of the hamster Orc1 protein for chromatin during the M-to-G1 transition correlate with the activity of hamster origin recognition complexes (ORCs) and the appearance of prereplication complexes at specific sites. Here we show that Orc1 is selectively released from chromatin as cells enter S phase, conv
American Society for Microbiology.