abnormal mitotic spindle assembly checkpoint constitutive activation of mitotic spindle assembly checkpoint 2020-07-27T10:59:55Z A cell cycle checkpoint phenotype in which the mitotic spindle assembly checkpoint is activated continuously. The mitotic spindle assembly checkpoint normally delays the metaphase/anaphase transition of a mitotic nuclear division until the spindle is correctly assembled and chromosomes are attached to the spindle. constitutive activation of mitotic cell cycle spindle assembly checkpoint The difference between this term and abolished deactivation of mitotic spindle assembly checkpoint (FYPO:0005726) is that this term describes cells in which the checkpoint is always active, i.e. the checkpoint is never observed to be "off", whereas FYPO:0005726 describes cells in which the checkpoint is not active at first, but once activated the checkpoint is not deactivated. constitutively activated of mitotic spindle assembly checkpoint midori FYPO:0007437