In eukaryotes, DNA replication is fired once in a single cell cycle before cell division starts to maintain stability of the genome. This event is tightly controlled by a series of proteins. Cdt1 is one of the licensing factors and is involved in recruiting replicative DNA helicase Mcm2-7 proteins into the pre-replicative complex together with Cdc6. In Cdt1, the C-terminal region serves as a binding site for Mcm2-7 proteins, although the details of these interactions remain largely unknown. Here, we report the structure of the region and the key residues for binding to Mcm proteins. We determined the solution structure of the C-terminal fragment, residues 450 -557, of mouse Cdt1 by NMR. The structure consists of a winged-helix domain and shows unexpected similarity to those of the C-terminal domain of Cdc6 and the central fragment of Cdt1, thereby implying functionalandevolutionaryrelationships.Structure-basedmutagenesis and an in vitro binding assay enabled us to pinpoint the region that interacts with Mcm proteins. Moreover, by performing in vitro binding and budding yeast viability experiments, we showed that ϳ45 residues located in the N-terminal direction of the structural region are equally crucial for recognizing Mcm proteins. Our data suggest the possibility that winged-helix domain plays a role as a common module to interact with replicative helicase in the DNA replication-licensing process.In eukaryotes, DNA replication is highly coordinated to retain the integrity of the genome. Whereas DNA replication in prokaryotes begins at a single site and stops at the end of the genome, eukaryotic genomes consist of multiple replication origins where DNA replication starts. These origins are synchronized so that they are activated only once in a single division cycle. A series of proteins, the origin recognition complex (ORC), 6 cell division cycle 6 homolog (Cdc6), chromatin licensing and DNA replication factor 1 (Cdt1), and minichromosome maintenance 2-7 (Mcm2-7) are known to play correlated roles in licensing (1-5). Oncogenic proliferation often causes abnormal expression of the proteins involved in the DNA-licensing process, thus emphasizing the importance of harmonious adjustments between these proteins (6). A complicated interaction network between these proteins has been reported (7), although the details at residue and atom levels remain largely unknown.Formation of a pre-replication complex at each origin is the first event in the replication process. ORC proteins bind initially to each replication origin of DNA. The DNA sequences of the origins where ORC binds have not been identified, except for those in Saccharomyces cerevisiae (8), suggesting that there may be other factors involved in addition to the sequences (9). The DNA strand at the origin needs to be unpaired to begin replication; therefore, the existence of replicative helicase is essential. Mcm2-7 proteins are believed to function as the replicative helicase in eukaryotes. Each Mcm2-7 protein consists of a conserved AAAϩ ATPase type C-termin...

Appropriate regulation of inflammation during the perioperative period is important for achieving a stable postoperative course and early recovery and for reducing the malignancy relapse rate. For these reasons, an immune-modulating diet that includes anti-inflammatory substances such as ω-3 fatty acids has been used widely in clinical settings. The amino acids cystine and theanine are both involved in the synthesis of glutathione (GSH), a strong antioxidant, and there have been several reports that oral cystine and theanine enhance immunoreactions. This study was a pilot study to assess the effect of perioperatively administering oral cystine and theanine in gastric surgery patients and suggested that oral administration of these amino acids may reduce inflammation and promote recovery after gastric surgery. IntroductionPreventing organ dysfunction and immune suppression by inhibiting excess inflammation is considered an important aspect of perioperative surgical management, and several studies have indicated that immunonutrition is effective for this purpose.1,2 Administering the amino acids cystine and theanine has been shown to significantly suppress increases in C-reactive protein (CRP) levels and neutrophil counts and decreases in the number of lymphocytes after excessive exercise, resulting in a reduction in excessive inflammation and immune dysfunction; similar effects are expected to result from immunonutrition. 3 Cystine is a sulfur-containing amino acid that consists of 2 cysteine molecules joined by a disulfide bond. 4 Transporters on cell membranes (including those of neutrophils, macrophages, and dendritic cells) mediate the uptake of cystine into cells, and then thioredoxin rapidly 798P ENXXX10.1177/0148607112458798Journal of Parenteral and Enteral Nutrition / Vol. AbstractBackground: It has been reported that cystine and theanine, amino acids related to glutathione synthesis, have immunomodulatory effects, such as suppressing inflammation after strenuous exercise. In this study, we examined the effects of oral administration of cystine and theanine during the perioperative period as a pilot study. Methods: Forty-three cases of distal gastrectomy for cancer conducted in our department were assigned to the cystine and theanine group (CT group) or to the placebo control group (P group), and a randomized, singleblind, parallel-group study was then performed. Cystine (700 mg) and theanine (280 mg) or a placebo was administered to participants for 10 continuous days (4 days before to 5 days after surgery). Changes in pre-and postoperative interleukin (IL)-6, C-reactive protein (CRP), albumin, white blood cell (WBC) count, neutrophil count, total lymphocyte count, resting energy expenditure (REE), and body temperature were compared and examined. Results: Ten patients were excluded, leaving 33 patients in the study. The CT group had significantly lower IL-6 values (postoperative day [POD] 4), CRP levels (POD 7), neutrophil counts (POD 4), and body temperatures (POD 5) than the P group (P < .05). In addi...

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