Late to the party here, but this excellent paper from 2010 identifies the E3 ubiquitin ligase CRBN as a target relevant to the teratogenic effects of thalidomide. Inhibition of CRBN (either genetically or using thalidomide) results in dysregulation of FGF expression crucial for limb outgrowth. A nice example of where a small molecule exactly mimics the effects of a gene disruption. Further, thalidomide can be used as a tool to study CRBN function.