Figure 4.

Splicing of haematopoietic genes in Usb1-deficient zebrafish. (A) sqRT-PCR analysis of neutrophil-specific genes, including mpx, ncf1, ela3l and npsn, in the embryos at 25 hpf. The decreased expression of the normal transcripts and the expression of aberrant transcripts retaining the introns were observed in Usb1-deficient embryos. (B–C) sqRT-PCR analysis of haematopoietic - but not neutrophil-specific genes in MO-injected and wild-type embryos. The normal transcripts of haematopoietic progenitors (B) and erythroid and myeloid-but not neutrophil-specific genes (C) were observed in the morphants. β-actin served as a control.