Nup133 Is Required for Proper Nuclear Pore Basket Assembly and Dynamics in Embryonic Stem Cells

Acute Heat Stress Leads to Reversible Aggregation of Nuclear Proteins into Nucleolar Rings in Fission Yeast

“…We next analyzed the localization of components of the Nup107-160 scaffold or Y-complex, which anchors the NB to the NPC (Asakawa et al, 2019;Souquet et al, 2018). We found that Nup85 and Nup132 behaved as Nup211 and Alm1 and dissociated from NPCs to accumulate in ring-like structures upon HS ( Figure 1C).…”

Integrity of the short arm of nuclear pore Y-complex is required for mouse embryonic stem cell growth and differentiation

“…Studies performed in mouse embryonic stem cell (mESCs) showed that Nup133 is dispensable for cell growth at the pluripotent stage, but is required for mESC differentiation (Lupu et al, 2008). In mESCs, Nup133 is dispensable for NPC scaffold assembly but required for the proper assembly of the nuclear pore basket (Souquet et al, 2018). However, it is not clear if the role of Nup133 in NPC basket assembly underlies its functions in cell differentiation More recently, Seh1, which is critical for proper mitotic progression in cancer cell lines (Platani et al, 2018;Platani et al, 2009;Zuccolo et al, 2007), was found to be required for differentiation of oligodendrocyte progenitors (Liu et al, 2019).…”

“…The viability of Seh1 -/-mESCs at the pluripotent stage and their impaired survival upon differentiation was reminiscent of the phenotype observed upon inactivation of Nup133, another member of the Y-complex (Lupu et al, 2008). Because Nup133 loss was recently demonstrated to affect NPC basket assembly (as revealed by lack of TPR staining in about 50% of the NPCs) (Souquet et al, 2018), we decided to examine the impact of Seh1 inactivation on NPC assembly. We therefore quantified the average fluorescence intensity at the nuclear envelope (NE) of TPR, Nup98 and Nup133 in WT and Seh1 -/-mESCs, using a GFP-tagged cell line for internal reference, as previously reported (Souquet et al, 2018;see Experimental procedures).…”

“…Because Nup133 loss was recently demonstrated to affect NPC basket assembly (as revealed by lack of TPR staining in about 50% of the NPCs) (Souquet et al, 2018), we decided to examine the impact of Seh1 inactivation on NPC assembly. We therefore quantified the average fluorescence intensity at the nuclear envelope (NE) of TPR, Nup98 and Nup133 in WT and Seh1 -/-mESCs, using a GFP-tagged cell line for internal reference, as previously reported (Souquet et al, 2018;see Experimental procedures). This analysis revealed a mild but significant reduction (in the range of 20-35%) of the signal of these three nucleoporins in Seh1 -/relative to WT mESCs (Fig.…”

“…Quantification of NPC density at the nuclear envelope (NE) was performed essentially as described (Souquet et al, 2018). To quantify nuclear surfaces, mESCs of interest were mixed with a GFP cell line of reference and grown on coverslips for 24 hr prior to fixation and immunostaining as described above.…”