Q$1$: You have isolated cells with three different mutations in the RTK receptor that responds to VEG$-$

F$,$ a growth factor. You grow these cells in the absence of VEG$-$F for five days, then add VEG$-$F for

five days, then you wash the cells to remove VEG$-$F and monitor their growth for another five days.

You also have cells with an unmutated RTK receptor

as a control.

Based on your data, match each mutant to the

best possible mechanism, using the options

below.

$1.$ Mutant receptor dimerizes in absence of

VEG$-$F

$2.$ Mutant receptor stays bound to VEG$-$F

$3.$ Mutant receptor cannot dimerize

$4.$ Mutant receptor overactivates downstream

signal

$5.$ Mutant receptor only weakly dimerizes

A drug called X$154$ disrupts VEG$-$F binding to the

receptor. X$154$ is a possible cancer treatment for

patients with mutant RTK receptors. Based on your

data, would you consider X$154$ as a treatment for

patents with each mutant receptor?

Best possible mechanism?

$($write the number from above$)$

Would you consider X$154$ as

a treatment for patients with

this mutant? $($yes or no$)$

Mutant $1$

Mutant $2$

Mutant $3$

Pick one mutant where you don$$t think the drug would be a good treatment, and explain why

in one sentence: