Question

You are interested in understanding the regulation of nuclear lamina assembly. To create an in vitro system for studying this process you start with partly purified nuclear lamina subunits to which you will add back purified cellular components to drive nuclear lamina assembly. Before you start doing experiments, your instructor suggests that you consider what type of conditions would be most amenable to the assembly of the nuclear lamina from its individual subunits in vitro. Which of the following additions do you predict would be most likely to enhance the assembly of the nuclear lamina?

a. addition of phosphatase inhibitors
b. addition of ATP
c. addition of a concentrated salt solution that is 10 times the concentration normally found in the nucleoplasm
d. addition of protein kinase inhibitors

Answer 1

d. addition of protein kinase inhibitors

Step-by-step explanation:

The nuclear lamina is a structure composed of intermediate filament type proteins that is located between the inner nuclear membrane and the peripheral chromatin of eukaryotic cells. The nuclear lamina is involved in diverse cellular processes including, among others, nuclear/chromatin organization, control of the cell cycle, differentiation, DNA replication, transcription, etc. It is known that the nuclear lamina disassembles during mitosis and post-translational phosphorylation at specific residues of the nuclear lamina proteins modulate the polymerization state of this lamina during the cell cycle. For example, in chicken, it has been shown that protein kinase C phosphorylation inhibits the nuclear import of lamin B2, a nuclear intermediate filament protein.