USMLE-STEP-1 Web TestEngine demo

an increase in the expression of pRB resulting in increased binding of pRB to E2F

hypophosphorylation of pRB so that it can no longer interact with E2F

loss of expression of pRB which normally activates E2F

mutation in pRB that prevents its phosphorylation so that it cannot interact with the gene to which it normally binds and coactivates with E2F

mutation in the domain of pRB to which E2F binds, the consequences of which lead to constitutive E2F activity