The hetero-hexameric origin recognition complex (ORC) is well known for its separable roles in DNA replication and heterochromatin assembly. However, ORC and its individual subunits have been implicated in diverse cellular activities in both the nucleus and the cytoplasm. Some of ORC's implied functions, such as cell cycle checkpoint control and mitotic chromosome assembly, may be indirectly re...

Secure information flow attempts to verify that programs do not leak information to unauthorized third parties. Previous approaches to secure information flow have considered classical sequential languages and concurrent languages based on channels. In this work, we demonstrate how techniques from secure information flow can be used to verify security properties of structured concurrent workflo...

The Organic Rankine Cycle (ORC) heat engine constitutes a very promising technology to recover waste heat (for instance from industry or from internal combustion engines) but also to exploit renewable energy sources (such as solar, biomass or geothermal energy). This seminar will emphasize how modeling and simulation tools could be used during the design stage of an ORC system in order to best ...

BACKGROUND The retinoblastoma (Rb) tumor suppressor protein can function as a DNA replication inhibitor as well as a transcription factor. Regulation of DNA replication may occur through interaction of Rb with the origin recognition complex (ORC). PRINCIPAL FINDINGS We characterized the interaction of Drosophila Rb, Rbf1, with ORC. Using expression of proteins in Drosophila S2 cells, we found...

In eukaryotes, the origin recognition complex (ORC) heterohexamer preferentially binds replication origins to trigger initiation of DNA replication. Crystallographic studies using eubacterial and archaeal ORC orthologs suggested that eukaryotic ORC may bind to origin DNA via putative winged-helix DNA-binding domains and AAA+ ATPase domains. However, the mechanisms how eukaryotic ORC recognizes ...

Plants have many polarized cell types, but relatively little is known about the mechanisms that establish polarity. The orc mutant was identified originally by defects in root patterning, and positional cloning revealed that the affected gene encodes STEROL METHYLTRANSFERASE1, which is required for the appropriate synthesis and composition of major membrane sterols. smt1(orc) mutants displayed ...

A new protein was cloned and identified as the sixth member of the human origin recognition complex (ORC). The newly identified 30-kDa protein hsORC6 is 28% identical and 49% similar to ORC6p from Drosophila melanogaster, which is consistent with the identities and similarities found among the other ORC members reported in the two species. The human ORC6 gene is located on chromosome 16q12. ORC...

In designing a language for distributed computing, the handling of data and distribution can be viewed as largely orthogonal concerns, as long as the data model supports the communication requirements of the distribution model. This view contrasts strongly with approaches based on distributed objects, which typically enforce a tight coupling of state and behavior. We have previously presented O...

The eukaryote-like DNA replication system of the model haloarchaeon Halobacterium NRC-1 is encoded within a circular chromosome and two large megaplasmids or minichromosomes, pNRC100 and pNRC200. We previously showed by genetic analysis that 2 (orc2 and orc10) of the 10 genes coding for Orc-Cdc6 replication initiator proteins were essential, while a third (orc7), located near a highly conserved...

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 until mitosis is completed and a nuclea...