Gid9, a second RING finger protein contributes to the ubiquitin ligase activity of the Gid complex required for catabolite degradation

► Gid9 is a second subunit of the Gid ubiquitin ligase complex containing a degenerated RING finger domain. ► It forms a dimer with the ubiquitin ligase confering RING finger subunit Gid2. ► Also the RING finger of Gid9 is required for ubiquitin ligase activity in vivo.