Question

Use the image to answer the question.

A researcher studying a line of cancer cells notices that cellular content of RhoBTB3 and Cyclin E1 increase and decrease through the cell cycle.

a. He hypothesizes that RhoBTB3 signaling regulates the production of Cyclin E1 and the entry of the cell into mitosis. Based on the data below, explain why his results do not support this hypothesis. Identify what conclusions are supported by this data.

b. Suppose that the researcher can engineer a cell line in which RhoBTB3 expression can be induced by the addition of a drug. Design an experiment using this cell line to test whether RhoBTB3 regulates the production of Cyclin E1. Describe what results he can expect if his hypothesis is correct.

Answer 1

I'm not sure about part b but here's the answer for part a

Explanation:

The experimental data shows that the RhoBTB3 expression increased after 12 hours and reached it's peak at 18 hours, which occurs in the G2 phase. The expression of Cyclin E1, however, started to increase after 8 hours, peaked at 14 hours, and remained there for 2 more hours before starting to decline. This shows that the highest level of the Cyclin E1 expression occurred in the S phase and initiated at the end of the G1 phase. His hypothesis is incorrect because if RhoBTB3 signaling did regulate the production of Cyclin E1, then the peak should have occurred prior to Cyclin E1.