A subset of basket nucleoporins relocalizes from the nuclear periphery to the nucleoplasm during anaphase I. (A) Schematic of the NPC, adapted from King et al. (2019). Nup100 and Nup145N are linkers between subcomplexes and are not depicted in the schematic. The gray background denotes the subcomplexes that comprise the NPC core; the red background denotes the nuclear basket. (B) A schematic depicting NPC remodeling during meiosis as described in King et al. (2019). Core nucleoporins are sequestered to the GUNC during meiosis II, while basket nucleoporins return to nascent gamete nuclei. (C) Quantification of nucleoporin detachment before (−10 min, “Pre”), coincident with (0 min, “Anaphase I”), and after (+10 min, “Post”) the onset of anaphase I. The detachment index (DI) for individual cells was calculated from single z-slices by dividing the average nucleoplasmic signal intensity by the average nuclear envelope signal intensity. For each nucleoporin (color-coded by subcomplex), individual DI values were normalized to the average DI at the “Pre” time point. Asterisks indicate statistical significance calculated using Dunn’s test for multiple comparisons when each nucleoporin was compared to Pom34-GFP, a transmembrane nucleoporin, for a given time point (see Materials and methods for an explanation as to why mean DI values for Pom34-GFP change at different meiotic stages; see Table S5 for P values). The dashed lines indicate the average DI for Pom34-GFP for each time point. Sample sizes (n) are the number of cells quantified for each nucleoporin; for Nup120-GFP and Nup49-GFP, cells from two independent replicates were pooled. For all figures in this article, mean and standard deviation are displayed as a dot and whiskers and significance values are denoted with asterisks: *, P < 0.05; **, P < 0.01; ***, P < 0.001; and ****, P < 0.0001. (D) Montage of a cell with Nup60-GFP, a nuclear basket nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB14646). (E) Montage of a cell with Mlp1-GFP, a nuclear basket nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB14648). (F) Montage of a cell with Pom34-GFP, a transmembrane nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB13503). For all panels, the onset of anaphase I was defined as the Htb1-mCherry chromatin mass exhibiting distortion from a spherical shape consistent with chromosome segregation. For each montage, normalized DI values are indicated when calculated. The white arrowheads in the “Fire LUT” images denote nuclei at the onset of anaphase I, the stage when Nup60-Nup2 detachment is observed. For all figures in this article, the “Merge” rows display both the GFP and RFP signals together, and the “Fire LUT” (LookUp Table) row displays the GFP signal pseudocolored using the Fire LUT in FIJI (Schindelin et al., 2012). A single white dot (see merged z-projection panels) denotes the time of the meiosis I remodeling event (defined as Nup60-Nup2 relocalization to the nucleoplasm) and two white dots denote the time of the meiosis II remodeling event (defined as near complete nuclear basket return to gamete nuclei). Scale bars, 2 μm.
Figure 1.

A subset of basket nucleoporins relocalizes from the nuclear periphery to the nucleoplasm during anaphase I. (A) Schematic of the NPC, adapted from King et al. (2019). Nup100 and Nup145N are linkers between subcomplexes and are not depicted in the schematic. The gray background denotes the subcomplexes that comprise the NPC core; the red background denotes the nuclear basket. (B) A schematic depicting NPC remodeling during meiosis as described in King et al. (2019). Core nucleoporins are sequestered to the GUNC during meiosis II, while basket nucleoporins return to nascent gamete nuclei. (C) Quantification of nucleoporin detachment before (−10 min, “Pre”), coincident with (0 min, “Anaphase I”), and after (+10 min, “Post”) the onset of anaphase I. The detachment index (DI) for individual cells was calculated from single z-slices by dividing the average nucleoplasmic signal intensity by the average nuclear envelope signal intensity. For each nucleoporin (color-coded by subcomplex), individual DI values were normalized to the average DI at the “Pre” time point. Asterisks indicate statistical significance calculated using Dunn’s test for multiple comparisons when each nucleoporin was compared to Pom34-GFP, a transmembrane nucleoporin, for a given time point (see Materials and methods for an explanation as to why mean DI values for Pom34-GFP change at different meiotic stages; see Table S5 for P values). The dashed lines indicate the average DI for Pom34-GFP for each time point. Sample sizes (n) are the number of cells quantified for each nucleoporin; for Nup120-GFP and Nup49-GFP, cells from two independent replicates were pooled. For all figures in this article, mean and standard deviation are displayed as a dot and whiskers and significance values are denoted with asterisks: *, P < 0.05; **, P < 0.01; ***, P < 0.001; and ****, P < 0.0001. (D) Montage of a cell with Nup60-GFP, a nuclear basket nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB14646). (E) Montage of a cell with Mlp1-GFP, a nuclear basket nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB14648). (F) Montage of a cell with Pom34-GFP, a transmembrane nucleoporin, and Htb1-mCherry, a histone, progressing through meiosis (UB13503). For all panels, the onset of anaphase I was defined as the Htb1-mCherry chromatin mass exhibiting distortion from a spherical shape consistent with chromosome segregation. For each montage, normalized DI values are indicated when calculated. The white arrowheads in the “Fire LUT” images denote nuclei at the onset of anaphase I, the stage when Nup60-Nup2 detachment is observed. For all figures in this article, the “Merge” rows display both the GFP and RFP signals together, and the “Fire LUT” (LookUp Table) row displays the GFP signal pseudocolored using the Fire LUT in FIJI (Schindelin et al., 2012). A single white dot (see merged z-projection panels) denotes the time of the meiosis I remodeling event (defined as Nup60-Nup2 relocalization to the nucleoplasm) and two white dots denote the time of the meiosis II remodeling event (defined as near complete nuclear basket return to gamete nuclei). Scale bars, 2 μm.

This Feature Is Available To Subscribers Only

or Create an Account

Close Modal
Close Modal