Kir7.1 regulates zebrafish neutrophil chemotaxis. (A) RT-PCR of indicated genes using mRNA extracted from FACS-sorted neutrophils. (B) Number of neutrophils recruited to the ventral fin induced by LTB4 in WT fish treated by ML133. (C–E) Representative tracks and quantification of speed and forward migration index (FMI) of mouse bone marrow PMN chemotaxis toward LTB4 after treatment with DMSO, BaCl₂, or VU590 in an under-agarose migration chamber plate coated with collagen IV. The lines represent individual cell trajectories over a 60-min period. N > 15 in each group. Data present mean ± SD, representative of three independent experiments. One-way ANOVA. (F) Schematic of the kncj13 knockout fish. (G and H) Quantifications of neutrophils recruited to the tail wound (G) or ventral fin induced by LTB4 (H) in kcnj13 KO fish. (I) Quantification of neutrophils recruited to the ventral fin induced by LTB4 in neutrophil-specific KCNJ13^Q153H mutant fish treated by VU590 or vehicle control. (H and I) The number of neutrophils in the fin was normalized to total neutrophil numbers to rule out developmental defects. (B, G, H, and I) Each dot represents one neutrophil. n > 20 in each group. Data representative of three independent experiments. Results are presented as mean ± SD, Mann–Whitney test. Source data are available for this figure: SourceData FS1.