Figure 1: Learning induces biphasic changes in stathmin activity and microtubule stability.

(a) Immunoblot estimation of stathmin phosphorylation at Ser16 (pS16), Ser25 (pS25) and Ser38 (pS38), 0.5, 1, 2, 8 or 24 h following contextual fear conditioning. N, naive. n=6 per group (pooled tissues from three to four mice per sample). *P<0.05 versus naive mice (post-hoc comparison). (b) Analysis of stathmin-tubulin protein interactions using co-immunoprecipitation. Stathmin–tubulin complexes are formed at 0.5 h and dissociate at 8 h after contextual fear conditioning. n=4 per group (pooled tissues from four to five mice per sample). *P<0.05 (post-hoc comparison). (c) Immunoblot estimation of detyrosinated (Detyr-) and tyrosinated (Tyr-) α-tubulin levels after contextual fear conditioning. n=6 per group (pooled tissues from three to four mice per sample). *P<0.05 versus naive mice (post-hoc comparison). (d) Experimental design for drug administration 8 h following contextual fear conditioning. Memory was tested 24 h after training. (e) Mice injected with nocodazole 8 h following training show reduced freezing. vehicle, n=11; nocodazole, n=12. *P<0.05 (Student’s t-test). (f) Mice injected with paclitaxel 8 h following training show increased freezing. vehicle, n=11; paclitaxel, n=12. *P<0.05 (Student’s t-test). Data are expressed as mean±s.e.m.