Table 1. Relative signaling potencies of recombinant forms of Shh ligand.
Recombinant Shh | Cell transfection | Conditioned Media | ||
EC50 (pg/cell) | Relative to Shh | EC50 (nM) | Relative to Shh | |
Shh | 0.0017 | 1 | 0.81 | 1 |
ShhC25A | 0.0077 | 4.5 | 5.04 | 6.2 |
ShhC25S | 0.0026 | 1.6 | 7.71 | 9.5 |
ShhN | 0.00093 | 0.6 | ND | ND |
ShhNC25A | ND | ND | 311 | 384 |
ShhNC25S | 0.0031 | 1.8 | 104.1 | 128.5 |
The half maximal effective concentration (EC50) of Shh and recombinant variants lacking one or both lipid modifications was determined in signaling assays with NIH3T3 fibroblasts that were either transfected with recombinant Shh, or to which Shh conditioned medium was added exogenously. ND, not determined.