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Fig. 5
(A) Quantitative RT-PCR of ncapg expression at 48 hpf. ncapg mRNA expression is down-regulated in banprw337 mutants and banp morphants. Unpaired t-test (two-tailed), Mean ± SD. [n=3, p**<0.01]. (B) ATAC-seq and RNA-seq analysis of ncapg mRNA transcription. In banprw337 mutants, chromatin access is reduced at the TSS of ncapg (ATAC-seq) and transcript expression is markedly decreased (RNA seq). (C) Quantitative RT-PCR of cenpt expression at 48 hpf. cenpt mRNA expression is down-regulated in banprw337 mutants and banp morphants. Unpaired t-test (two-tailed), Mean ± SD. [n=3, p**<0.01]. (D) ATAC-seq and RNA-seq analysis of cenpt mRNA transcription. In banprw337 mutants, chromatin access is reduced at the TSS of cenpt (ATAC-seq) and transcript expression is markedly decreased (RNA seq). (E) Time-lapse images of mitosis of retinal progenitor cells injected with banp 5misMO (upper) and banp MO (lower) at 2 dpf using Tg [h2afv: GFP; EF1α: mCherry-zGem] transgenic zebrafish. In retinas injected with banp 5misMO, mitosis proceeds sequentially from prophase (t=5–10 min), metaphase (t=16 min), anaphase (t=21 min), and telophase (t=24 min). On the other hand, in banp morphant retinas, the duration of mitosis from prophase to telophase was 67 min, significantly longer than that of the control MO (24 min). Furthermore, a prophase-like chromosome arrangement appeared abnormally (t=59) after several metaphase-like alignments (t=36 and 46), followed by anaphase (t=64) and telophase. Scale bar: 5 μm. (F) Violin plot of the duration of mitosis from prophase to telophase in retinas injected with banp 5misMO and banp MO. Mitosis in banp morphants is significantly longer than that of banp 5misMO injected embryos. Mann Whitney test, Mean ± SD. [n=3, p****<0.0001] (G) Confocal images of metaphase cells in zebrafish retinas at 48 hpf. The mitotic spindle is labeled with anti-α-tubulin antibody, whereas metaphase chromosomes are labeled with anti-pH3 antibody. The mitotic spindle is correctly attached to metaphase chromosomes in wild-type retinal cells (left panel). On the other hand, mitotic cells in banprw337 mutants exhibit inefficient mitotic spindle attachment and poorly orientated metaphase chromosomes (right panels). Dotted circles indicate the outline of metaphase cells. Scale bar: 2 μm. (H) Percentage of cells with normal and abnormal spindle attachment in wild-type and banprw337 mutant embryos. Two-way ANOVA with Šídák’s multiple comparisons test, Mean ± SD. [n=3, p****<0.0001].
Banp promotes transcription of chromosome segregation regulators, cenpt and ncapg.