Extended Data Fig. 7: NCAPG2 nuclear enrichment is critical for timely chromosome condensation in mouse oocytes.
From: Condensin dysfunction is a reproductive isolating barrier in mice
a, Hybrid oocytes expressing spretus NCAPG2-eGFP were fixed at metaphase I and stained for NCAPD3 and eGFP. NCAPD3 intensities on chromosomes were quantified (n = 61 and 48 oocytes for control and spretus NCAPG2-eGFP, respectively); unpaired t-test (two-sided) was used for statistical analysis; *P = 0.0423. b, Hybrid oocytes expressing domesticus NCAPG2-eGFP, spretus NCAPG2-eGFP or spretus NCAPG2-NES-eGFP were fixed at prophase I and stained for eGFP. Nuclear/cytoplasmic ratios of eGFP intensities were quantified; each dot in the graph represents a single oocyte (n = 37, 31, 40 and 29 oocytes for control, domesticus NCAPG2-eGFP, spretus NCAPG2-eGFP and spretus NCAPG2-NES-eGFP, respectively); unpaired t-test (two-sided) was used for statistical analysis; ****P < 0.0001. c, Hybrid oocytes expressing spretus NCAPG2-eGFP or spretus NCAPG2-NES-eGFP were fixed at prophase I and stained for NCAPG2 and eGFP. NCAPG2 intensities in the nucleus were quantified; each dot in the graph represents a single oocyte (n = 16, 25 and 30 oocytes for control, spretus NCAPG2-eGFP and spretus NCAPG2-NES-eGFP, respectively); unpaired t-test (two-sided) was used for statistical analysis; *P = 0.0165, ****P < 0.0001. Specifically, the spretus NCAPG2-eGFP overexpression increased the total NCAPG2 levels in the nucleus. d, Hybrid oocytes expressing spretus NCAPG2-eGFP or spretus NCAPG2-NES-eGFP were fixed either at prometaphase I or metaphase I and stained for eGFP and TOP2A. White arrowheads indicate stretched centromeres. eGFP intensities on chromosomes (prometaphase I: n = 37, 37 and 25 oocytes for control, spretus NCAPG2-eGFP and spretus NCAPG2-NES-eGFP, respectively; metaphase I: n = 61, 48 and 43 oocytes for control, spretus NCAPG2-eGFP and spretus NCAPG2-NES-eGFP, respectively; each dot represents a single oocyte) and the major satellite length in prometaphase I were quantified (n = 488, 549 and 368 chromosomes for control, spretus NCAPG2-eGFP and spretus NCAPG2-NES-eGFP, respectively; each dot represents a single centromere); unpaired t-test (two-sided) was used for statistical analysis; ****P < 0.0001. Images are maximum intensity z projections to show all chromosomes or optical slices to show individual chromosomes; red line, mean; scale bars: 5 µm.
