Figure 3.

Morpholino knockdown of miR-31 induces apoptosis in the CNS and tail. Embryos injected with control (a–d) or miR-31 MO (e–h) were stained with acridine orange (AO) at 48 hpf. Apoptotic cells are shown as bright green spots or red spots, and less bright homogenous green or black is unspecific background staining. (b–d) Control MO zebrafish exhibited few or no apoptotic cells in the whole body. In contrast, high staining was observed throughout the CNS and tail in zebrafish injected with 8 ng of miR-31 MO (f–h, white arrows, and black arrows). (i–n) Quantification of apoptotic bodies at the spinal cord shows a 122-fold increase in miR-31 morphants (n = 10) at 48 hpf. A-M: lateral view, anterior, left; hpf: hours post-fertilization. Columns, mean; bars, SEM. (A color version of this figure is available in the online journal.)