Dictionary > Gap 2-M DNA damage checkpoint

Gap 2-M DNA damage checkpoint

Definition
noun
(cell biology) A control mechanism in G2 phase of the cell cycle that ensures the cell is ready for cell division
Supplement
In eukaryotes, the cell cycle is a cyclical series of biological events that certain asexual cells go through. The cell cycle is comprised of these fundamental events, particularly (1) resting phase (Gap 0), (2) interphase (Gap 1, S phase, Gap 2), and (3) cell division (i.e. mitotic phase and cytokinesis). In the interphase, the two major highlights are cell growth (particularly increase in size) and DNA replication. DNA replication occurs particularly during the S phase of the interphase. The S phase is a period in between two gap phases: Gap 1 and Gap 2. These two gap phases of the interphase are focused at increasing in cell size and production of proteins essential to the subsequent events. For instance, histones are produced during Gap 1 for DNA replication in the S phase whereas certain proteins are produced during Gap 2 to ensure that the cell is ready for subsequent cell division. The cell has a Gap 2-M DNA damage checkpoint system. It is a control mechanism that ensures the cell has repaired possible errors in DNA after being replicated prior to entering cell division. This checkpoint mechanism involves an active Cdk1 (cdc2) complexed to cyclin B1. The cdc2- B1 complex is required to progress from G2 phase to mitotic phase. It is regulated by inhibitory phosphates at a pair of amino acids in the roof of the active site by Wee1. These sites are dephosphorylated by the action of the phosphatase Cdc25C. The dephosphorylation leads to the increased Cdk activity. In the presence of DNA damage, the Chk1 is activated. It activated Chk1 inactivates the Cdc25C by phosphorylating cdc25C. This leads to the phosphorylation and inactivity of the complex cdc2-B1 and then to G2-M arrest.1
Abbreviation / Acronym:

  • G2-M DNA damage checkpoint
  • G2/M checkpoint
  • G2-M checkpoint

See also:

  • Gap 2 phase
  • cell cycle
  • interphase
  • Reference(s):

    1 DiPaola, R. S. ().To Arrest or Not To G2-M Cell-Cycle Arrest. Clin Cancer Res. 2002 Nov;8(11):3311-4. Retrieved from ://clincancerres.aacrjournals.org/content/8/11/3311.


    You will also like...

    Pollution in Freshwater Ecosystems
    Pollution in Freshwater Ecosystems

    There are many environmental factors that arise due to the usage of water in one way or another and for every action tha..

    kinesin motor proteins transporting molecules across microtubules
    Movement of Molecules Across Cell Membranes

    Molecules move within the cell or from one cell to another through different strategies. Transport may be in the form of..

    sponge
    Primitive Animals

    Life, as we know it today, is presumed to have started in the sea and many of them were likely eukaryotic animal-like or..

    Geological Periods
    Geological Periods

    Geological periods is a study guide that cites the different geological periods on Earth's timeline. Each has a brief ov..

    A sperm cell fertilizing an ovum
    Human Reproduction and Fertilization

    For human species to obviate extinction, reproductive mature adults should be producing viable offspring in order to con..

    A chart depicting Mendel's Law of Dominance
    Mendel’s Law & Mendelian Genetics

    One of Mendel’s law of inheritance is the “law of dominance”. Read this tutorial to know more about this form of i..

    Related Articles...

    No related articles found

    See all Related Topics