Cdc6/Orc1 from Pyrococcus furiosus may act as the origin recognition protein and Mcm helicase recruiter.

Archaea have one or more Cdc6/Orc1 proteins, which share sequence similarities with eukaryotic Cdc6 and Orc1. These proteins are involved in the initiation process of DNA replication, although their specific function has not been elucidated, except for origin recognition and binding. We showed that the Cdc6/Orc1 protein from the hyperthermophilic archaeon Pyrococcus furiosus specifically binds to the oriC region in the whole genome.

Localized melting of duplex DNA by Cdc6/Orc1 at the DNA replication origin in the hyperthermophilic archaeon Pyrococcus furiosus.

The initiation step is a key process to regulate the frequency of DNA replication. Although recent studies in Archaea defined the origin of DNA replication (oriC) and the Cdc6/Orc1 homolog as an origin recognition protein, the location and mechanism of duplex opening have remained unclear. We have found that Cdc6/Orc1 binds to oriC and unwinds duplex DNA in the hyperthermophilic archaeon Pyrococcus furiosus, by means of a P1 endonuclease assay.

Gray-scale and color Doppler sonographic features of the vaginal cuff and cervical remnant after hysterectomy.

Objective: The purpose of this study was to define the sonographic characteristics of the vaginal cuff and cervical remnant after hysterectomy and to establish normal measurements of each after each type of surgery.

Materials And Methods: One hundred twenty-one women who had undergone hysterectomy (mean age, 51 years; range, 31-80 years) were studied using transabdominal or transvaginal sonography. Seventy-six patients were acquired retrospectively and 45 prospectively.