The Cell Cycle

The representation of the cell cycle in GO is split into two sections: the physical processes that occur and the temporal stages—prophase, anaphase and so on—used to describe sets of events. This method of representation is used to prevent true path problems when organisms differ from the "canonical" (usually S. cerevisiae) cell cycle.

Terms and Structure

The cell cycle node sits under cellular process ; GO:0007049 and is split into types of cell cycle (meiotic or mitotic) and stages (M phase, S phase, etc.), plus a regulation term.

  • cell cycle
    • [p] interphase
      • [i] interphase of meiotic cell cycle
      • [i] interphase of mitotic cell cycle
      • p] S phase
      • [p] G1 phase
      • [p] G2 phase
    • [p] M phase
    • [i] meiotic cell cycle
    • [i] mitotic cell cycle
    • [p] regulation of cell cycle

Taking the example of M phase of the mitotic cell cycle, this is the structure of the child terms of M phase. Note that the terms representing temporal phases are not linked to those representing physical events.

  • M phase of mitotic cell cycle
    • [p] mitotic anaphase
    • [p] mitotic metaphase
    • [p] mitotic prometaphase
    • [p] mitotic prophase
    • [p] mitotic sister chromatid segregation
    • [p] mitotic telophase
    • [p] regulation of mitosis

The physical events associated with mitotis and meiosis are mainly found under the term chromosome segregation, defined as "the process in which genetic material, in the form of chromosomes [or chromatids], is organized and then physically separated and apportioned to two or more sets". The related term chromosome separation refers to the detachment of chromosomes from each other as they move towards the spindle pole.

  • mitotic sister chromatid segregation
    • [p] attachment of spindle microtubules to kinetochore during mitosis
    • [p] attachment of spindle microtubules to mitotic chromosome
    • [p] mitotic chromosome condensation
    • [p] mitotic chromosome decondensation
    • [p] mitotic chromosome movement towards spindle pole
    • [p] mitotic metaphase plate congression
    • [p] mitotic sister chromatid cohesion
    • [p] mitotic sister chromatid separation

Standard Definitions

any cell cycle phase (e.g. M phase, telophase)
Progression through [phase name], [description of phase].
any cell cycle process (e.g. mitotic chromosome condensation)
The cell cycle process whereby [description of process].


Cytokinesis is placed under cell division but not under cell cycle, something which seems counterintuitive to many. This is because bacteria, which do not have a cell cycle, undergo cytokinesis. Organisms that do have a cell cycle can use more specific terms, such as cytokinesis after meiosis I and cytokinesis after mitosis to represent cytokinesis in their organism.