Question

A rat cell and a chimpanzee cell are fused together. Antibodies to chimpanzee membrane antigens are labeled with rhodamine (a red fluorescent molecule) and antibodies against rat antigens are labeled with fluorescein (a green fluorescent molecule). What do the cells look like immediately after fusion? What about 40 minutes later? If the temperature of the cell is increased, what should happen?

Answer 1

Initially, the fused rat-chimpanzee cell would show separate green and red fluorescence, which would begin to mix after 40 minutes due to the fluidity of the cell membranes. Increasing the temperature would likely accelerate this mixing due to increased membrane fluidity.

Step-by-step explanation:

Immediately after fusion of a rat cell and a chimpanzee cell, the combined cell would show two distinct colors when fluorescently-labeled antibodies are applied: rat membrane antigens labeled with fluorescein would glow green, and chimpanzee membrane antigens labeled with rhodamine would glow red.

The distribution of these colors would initially be separate, reflecting the original cell membranes.

After 40 minutes, the fluorescent colors would begin to mix, demonstrating the fluidity of cell membranes.

This indicates that the membrane proteins are not static but can move laterally and mingle, suggesting a mixing of rat and chimpanzee membrane components due to the fluid mosaic nature of membranes.

If the temperature of the cell is increased, we can expect this mixing process to accelerate because membrane fluidity generally increases with temperature, facilitating faster diffusion of membrane proteins.