Problem:
Question 1: Compare and contrast the mechanisms by which SHP1 and SOCS proteins modulate erythropoietin signaling. Be specific.
Question 2: Describe the function of the PTEN phosphatase in the PI3K signaling pathway. Why is a loss-of-function mutation in PTEN cancer-promoting? Predict the effect of constitutively active PTEN on cell growth and survival.
Please read all the questions carefully and answer them.