Question

You add a drug to mitotic cells that inhibit the activity of an enzyme that dephosphorylates nuclear lamins. What do you predict will happen to these cells?

Answer 1

Inhibition of the dephosphorylation of nuclear lamins would likely result in a failure to reform the nuclear envelope, leading to the arrest of the cell cycle or apoptosis.

Step-by-step explanation:

If a drug inhibits the enzyme responsible for dephosphorylating nuclear lamins, then the dephosphorylation step of nuclear lamina disassembly is hindered. Normally during mitosis, nuclear lamins are phosphorylated to disassemble the nuclear envelope, allowing for the segregation of chromosomes. Once chromosomes have been segregated into the daughter cells, nuclear lamins are dephosphorylated to allow the reformation of the nuclear envelope around the newly formed nuclei. An inhibitor of this dephosphorylation would mean that the nuclear envelope cannot be reformed properly, resulting in a failure to complete cell division. This might either lead to cell cycle arrest or apoptosis, as the cell cannot successfully complete mitosis.