Figure 10

AX-1 does not promote outgrowth of granule cell axons. (a-f) When granule cells were cultured on AX-1 as a substrate they failed to extend neurites, no matter whether they expressed AX-1 (a-c) or not (d-f). Granule cells were electroporated with dsRNA derived from AX-1 and the EGFP plasmid in vitro, before they were cultured on AX-1 substratum (d-f) and compared with cells electroporated with the EGFP plasmid only (a-c). (g-l) On laminin substratum, both granule cells expressing AX-1 (g-i) and those lacking AX-1 (j-l) extended axons. Granule cells were identified by Pax6 expression (a,d,g,j). Electroporated cells expressed EGFP (b,e,h,k). Merged images are shown in (c,f,i,l). Asterisks indicate electroporated granule cells identified by EGFP and Pax6 expression. Open arrows label axons from Pax6-positive neurons that also express EGFP. Bars: 25 μm in (a-f) and 50 μm in (g-l).