Figure 4: Effect of RhoGAP on axon regeneration.
From: Axotomy-induced HIF-serotonin signalling axis promotes axon regeneration in C. elegans
(a) Structure of RGA-5. Schematic diagrams of RGA-5 and its human counterpart are shown. Domains are shown as follows: a GTP binding domain (GBD) and a Rho GAP domain (GAP). The bold line underneath indicates the extent of the deleted region in the rga-5(ok2241) mutant. (b) A two-hybrid assay for the interaction of RGA-5 with RHO-1. The reporter strain PJ69-4A was co-transformed with expression vectors encoding GAL4 DBD-RHO-1 (T19N) (GDP), GAL4 DBD-RHO-1 (G14V) (GTP), GAL4 DBD-CED-10 (G12V) (GTP), GAL4 DBD-CDC-42 (G12V) (GTP) and GAL4 AD-RGA-5 (GAP domain) as indicated. (c) Representative D-type motor neurons in wild-type animals and wild-type animals overexpressing RGA-5 GAP domain 24 h after laser surgery. In wild-type animals, severed axons have regenerated growth cones (orange arrowhead). In wild-type animals overexpressing the RGA-5 GAP domain, the proximal end of axon failed to regenerate (white arrowhead). Scale bar=20 μm. (d) Percentages of axons that initiated regeneration 24 h after laser surgery. Error bars indicate 95% CI. ***P<0.001; **P<0.01; *P<0.05; NS, not significant (Fisher’s exact test, two-tailed, n≥50). CI, confidence interval.
