:
Selected transcription factors have critical roles to play in organism survival by regulating the expression of
genes that control the adaptations needed to handle stress conditions. The retinoblastoma (Rb) protein coupled with the E2F
transcription factor family was demonstrated to have roles in controlling the cell cycle during freezing and associated
environmental stresses (anoxia, dehydration). Rb phosphorylation or acetylation at different sites provide a mechanism for
repressing cell proliferation that is under the control of E2F transcription factors in animals facing stresses that disrupt
cellular energetics or cell volume controls. Other central regulators of the cell cycle including Cyclins, Cyclin dependent
kinases (Cdks), and checkpoint proteins detect DNA damage or any improper replication, blocking further progression of
cell cycle and interrupting cell proliferation. This review provides an insight into the molecular regulatory mechanisms of
cell cycle control, focusing on Rb-E2F along with Cyclin-Cdk complexes typically involved in development and
differentiation that need to be regulated in order to survive extreme cellular stress.
