Concept
Wee1
Concepts associés (7)
Cyclin-dependent kinase 1
Cyclin-dependent kinase 1 also known as CDK1 or cell division cycle protein 2 homolog is a highly conserved protein that functions as a serine/threonine protein kinase, and is a key player in cell cycle regulation. It has been highly studied in the budding yeast S. cerevisiae, and the fission yeast S. pombe, where it is encoded by genes cdc28 and cdc2, respectively. With its cyclin partners, Cdk1 forms complexes that phosphorylate a variety of target substrates (over 75 have been identified in budding yeast); phosphorylation of these proteins leads to cell cycle progression.
Cdc25
Cdc25 is a dual-specificity phosphatase first isolated from the yeast Schizosaccharomyces pombe as a cell cycle defective mutant. As with other cell cycle proteins or genes such as Cdc2 and Cdc4, the "cdc" in its name refers to "cell division control". Dual-specificity phosphatases are considered a sub-class of protein tyrosine phosphatases. By removing inhibitory phosphate residues from target cyclin-dependent kinases (Cdks), Cdc25 proteins control entry into and progression through various phases of the cell cycle, including mitosis and S ("Synthesis") phase.
Cell cycle checkpoint
Cell cycle checkpoints are control mechanisms in the eukaryotic cell cycle which ensure its proper progression. Each checkpoint serves as a potential termination point along the cell cycle, during which the conditions of the cell are assessed, with progression through the various phases of the cell cycle occurring only when favorable conditions are met. There are many checkpoints in the cell cycle, but the three major ones are: the G1 checkpoint, also known as the Start or restriction checkpoint or Major Checkpoint; the G2/M checkpoint; and the metaphase-to-anaphase transition, also known as the spindle checkpoint.
Kinase dépendante des cyclines
vignette|350px|Schéma du cycle cellulaire. Cercle extérieur: I=Interphase, M=Mitose; cercle intérieur: M=Mitose et cytocinèse; G1=Phase G1; S=Phase S; G2=Phase G2. La durée de la mitose par rapport aux autres phases du cycle cellulaire est exagérée dans ce diagramme Les kinases dépendantes des cyclines (en anglais, cyclin-dependent kinase ou CDK) sont une famille de protéines kinases qui jouent un rôle majeur dans la régulation du cycle cellulaire.
G2 phase
DISPLAYTITLE:G2 phase G2 phase, Gap 2 phase, or Growth 2 phase, is the third subphase of interphase in the cell cycle directly preceding mitosis. It follows the successful completion of S phase, during which the cell’s DNA is replicated. G2 phase ends with the onset of prophase, the first phase of mitosis in which the cell’s chromatin condenses into chromosomes. G2 phase is a period of rapid cell growth and protein synthesis during which the cell prepares itself for mitosis.
Cyclines (protéines)
thumb|Expression des cyclines au cours du cycle cellulaire. Les cyclines sont une famille de plusieurs protéines impliquées dans la régulation du cycle cellulaire. Au moment d'agir pendant le cycle cellulaire d'une jeune cellule, les cyclines sont produites et interagissent avec leurs protéines kinases cycline-dépendantes (Cdk) spécifiques afin de les activer en formant des facteurs de promotion de la maturation, ce qui déclenchera la progression de la cellule vers l'interphase.
Kinase
380px|vignette|Schéma de fonctionnement des kinases Les kinases, (catalyseurs de la phosphorolyse), sont des enzymes du groupe des transférases catalysant les réactions de phosphorylation par l'ajout d'un ion phosphate à une molécule cible à partir de l'ATP. La molécule cible, appelée le substrat, peut être une protéine, un lipide, un sucre ou encore une kinase. Les kinases sont plus ou moins spécifiques et sont régulées par des combinaisons de seconds messagers.