Figure 2 from Tumor suppressor mechanisms in immune aging Biology Diagrams Mitosis is controlled by a network of kinases and phosphatases. We screened a library of small interfering RNAs against a genome-wide set of phosphatases to comprehensively evaluate the role of human phosphatases in mitosis. We found four candidate spindle checkpoint phosphatases, including the tumor suppressor CDKN3.
Molecular genetic studies of familial cancer syndromes identified and defined the recessive nature of tumor suppressor genes and resolved the paradox of why tumors arising in such families exhibited an autosomally dominant pattern of inheritance. Subsequent characterization of tumor suppressor proteins revealed their widespread involvement in sporadic cancers and pinpointed key mechanisms that
The tumor suppressor CDKN3 controls mitosis Biology Diagrams
Following mitosis, RB1 is partly dephosphorylated and the hypophosphorylated state is restored. In this fashion, RB1 switches between hypophosphorylated and hyperphosphorylated states during the cell cycle. For instance, PTEN is a negative regulator of the PI3K pathway and a classical tumor suppressor, Mitosis is crucial for cell division, and its errors can lead to cancer development by causing uncontrolled cell growth. Each mutation type has a unique pathway leading from normal cellular behavior to cancerous growth. Loss of Tumor Suppressor Genes: When genes that normally inhibit cell division are lost or mutated, unchecked
A tumor suppressor may possess multiple mechanisms to suppress cancer cell growth 3. For example, the most important tumor suppressor p53, which is associated with about 50% of human cancer cases 7, can trigger DNA repair processes, induce the transcription of other tumor suppressors, such as p21 and p16, and initiate cell apoptosis 3, 8, 9.
Edged Sword: How Oncogenes and Tumor Suppressor Genes Can ... Biology Diagrams
The PLK1-Mps1 pathway plays an important role in mitotic checkpoint complex (MCC) assembly. It is likely that DAB2IP acts as a scaffold to aid PLK1-Mps1 in targeting Cdc20. Depletion or loss of the Cdks-mediated phosphorylation of DAB2IP destabilizes the MCC, impairs the SAC, and increases chromosome missegregation and subsequent CIN, thus
Mastl acts as a regulator of mitotic progression by promoting the inactivation of the tumor suppressor protein phosphatase 2A (PP2A) associated with the B55δ regulatory subunit (Castilho et al., 2009; Vigneron et al., 2009; Burgess et al., 2010). Inactivation of PP2A/B55δ during mitosis is required to keep cyclin B1/Cdk1 activity high.
