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[Functions of p21Waf1 in norm and in stress]

O V Timofeev, T V Pospelova, V A Pospelov

    Molekuliarnaia Biologiia
    |August 3, 2004
    PubMed

    Insights

    The cell cycle inhibitor p21 (Waf1/Cip1/Sdi1/CAP20) is crucial for DNA damage response and cell cycle arrest. Its functions extend to differentiation, senescence, and apoptosis, influenced by cell state and modifications.

    Area of Science:

    • Molecular Biology
    • Cell Biology
    • Biochemistry

    Context:

    • The protein p21 (Waf1/Cip1/Sdi1/CAP20) is a key regulator of the cell cycle.
    • It plays a critical role in arresting the cell cycle at the G1/S checkpoint following DNA damage.
    • p21 is also implicated in the formation of active cyclin-kinase complexes, notably cyclin D-Cdk4/6.

    Purpose:

    • To review the multifaceted roles of p21 (Waf1/Cip1/Sdi1/CAP20) beyond its canonical cell-cycle control functions.
    • To explore how p21's activity is modulated by cellular context and posttranslational modifications.
    • To elucidate the structural, functional, and interactive properties of p21.

    Summary:

    • p21 (Waf1/Cip1/Sdi1/CAP20) is essential for cell cycle arrest and DNA damage response.
    • Emerging evidence highlights its involvement in cellular differentiation, senescence, and apoptosis.
    • Its functional balance is dynamically regulated by cellular state, interactions with other proteins, and posttranslational modifications like phosphorylation and proteolysis.

    Impact:

    • Understanding p21's diverse functions provides insights into cellular responses to stress and oncogenic stimuli.
    • Elucidating p21's regulatory mechanisms can reveal new therapeutic targets for cancer and other diseases.
    • This review consolidates current knowledge on p21 structure, modification, and interactions, facilitating further research into its complex roles in cellular processes.

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