Many features of _ cells make them suitable for biochemical studies of the cell-
ID: 43049 • Letter: M
Question
Many features of _ cells make them suitable for biochemical studies of the cell-cylce control system. For example, the cells are unusually large and are arrested in a _ -like phase. When the cells are triggered to recume cycling, the cell divisions have especially _ G1 and G2 phases and occur _. Studies with Xenopus eggs identified a partly purified activity called _ that drives a resting Xenoupus oocyte into M phase. MPF activity was found to _ durring the cell cycle, althouh the amount of its kinase component, called _, remained constant. The regulatory component of MPF, called _, has a _ effect on MPF activity and plays a part in regulating interactions with its _s. The components of MPF are ecolutionarily _ from yeast to humans, so that the corresponding human genes are _ to function in yeast.
Explanation / Answer
Many features of egg cells make them suitable for biochemical studies of the cell-cycle control system. For example, the cells are unusually large and are arrested in a G2 -like phase. When the cells are triggered to resume cycling, the cell divisions have especially long G1 and G2 phases and occur synchronously.
Studies with Xenopus eggs identified a partly purified activity called maturation promoting factor (MPF) that drives a resting Xenopus oocyte into M phase. MPF activity was found to oscillate during the cell cycle, although the amount of its kinase component, called Cdk, remained constant. The regulatory component of MPF, called cyclin, has a stimulatory effect on MPF activity and plays a part in regulating interactions with its substrates.
The components of MPF are evolutionarily conserved from yeast to humans, so that the corresponding human genes are able to function in yeast.