Fig. 7

Rac regulates microtubule disassembly-mediated neutrophil motility. (A) rac2 MO inhibits microtubule depolymerization-induced neutrophil motility. Neutrophil motility was tracked for 30minutes in Tg(mpx:GFP-UtrCH). (B) Rac2 knockdown makes neutrophils round, but nocodazole treatment makes Rac2-inhibited cells more round. n = 53 (Control, DMSO), 52 (Control, Noc), 36 (rac2 MO, DMSO) and 44 (rac2 MO, Noc). (C) Rac2 knockdown makes neutrophils compact, but nocodazole treatment makes Rac2-inhibited cells more compact. n = 54 (Control, DMSO), 52 (Control, Noc), 36 (rac2 MO, DMSO) and 44 (rac2 MO, Noc). (D) Transgenic neutrophil specific expression of dominant negative Rac2 D57N inhibits microtubule depolymerization-induced neutrophil motility. Neutrophil motility was tracked for 30minutes in Tg(mpx:mCherry-2A-Rac2D57N). (E) Affinity precipitation assays with GST-RBD and GST-PBD to detect Rho-GTP and Rac-GTP, respectively (n = 3). Microtubule disassembly directly activates Rac in addition to Rho in primary human neutrophils. Data in A and D are representative of at least three time-lapse movies. Three time-lapse movies were analyzed for data for B and C. Data in E are means ± s.e.m. of three separate experiments. *P<0.05, one-way ANOVA with Bonferroni post-test (B,C) and two-tailed paired t-test (E).