GLI1 is ubiquitinated by ITCH and subsequently degraded by the proteasome. ITCH-mediated degradation of GLI1 does not depend on the Dc or Dn degrons required for interaction with beta-TrCP, but instead relies on a novel PPXYs/pSP degron of GLI1 (di Marcotullio et al, 2006, 2011; Huntzicker et al, 2006).
