NUP-1 is necessary for cell growth and maintenance of nuclear architecture.

<p>NUP-1 RNAi was induced in both BSF and PCF cells. (A, B) NUP-1 mRNA was depleted by ∼30% as measured by qRT-PCR normalized to β-tubulin, corresponding to a ∼75% decrease in NUP-1 protein after 24 h of RNAi induction. Western bands were quantified, normalized to BIP levels, and represented as bar graphs. Error bars are the result of two experimental replicates. (C) IFA using DAPI to visualize DNA (blue). Nuclei of control cells were ovoid with well-defined boundaries, and induced cells exhibited nuclei with diffuse boundaries (i.e., rather than the DAPI nuclear signal being sharply demarcated, the signal gradually decreases with distance from the nuclear centre), and abnormal protrusions (blebs) in both BSF (left panel) and PCF (right panel) cells are seen. Bar: 5 µm. (D) Nuclei with abnormal extensions (blebbing) and with diffuse boundaries were examined over a time course of NUP-1 RNAi induction in BSF cells. 200 cells were scored for each time point. Percentage of nuclei with blebbing or diffuse phenotypes is shown, with the remainder of cells demonstrating a normal phenotype. Initially an increase in cells with bleb nuclei (black) was observed, followed by a decrease in bleb nuclei and an increase in cells with diffuse nuclei (gray). Note that these features are present at less than 1% in an uninduced population. Bar: 2 µm. (E) NUP-1 knockdown BSF cells were probed with an anti-NUP-1 antibody (white). DAPI is used to visualize DNA (blue). Shown are serial sections along the <i>z</i>-axis. Bar: 2 µm.