Question

[Biochemistry]

-Mutant Ras proteins have been found to be associated with various types of cancer. What is the effect on a cell if the mutant Ras is able to bind GTP but is unable to hydrolyze it?

-Affinity chromatography is often used as a technique to purify cell-surface receptors. Describe the steps you would take to purify a cell-surface receptor using this technique

Answer 1

Mutations in Ras proteins create mutant Ras proteins which are oncogenic . Usually Ras proteins will bind to GTP and hydrolyze them but mutant Ras proteins will bind to GTP and will not hydrolyze them . Ras proteins will get stuck in the active form( permanently activated) and overactive signalling inside the cell even in the absence of incoming growth signals .Thus will result in uncontrolled cell proliferation.