OLIG2 and glioblastoma: Using De-IP in lysates prepared from mouse spinal cord tissue and human GBM, we detected a weak but nonetheless clear band of ~52 kD, which corresponds to the estimated molecular weight of SUMOylated Olig2 (~37 kD for the endogenous Olig2 plus ~15 kD for SUMO1) (Fig. 1d, e).