Component of the CTLH E3 ubiquitin-protein ligase complex that selectively accepts ubiquitin from UBE2H and mediates ubiquitination and subsequent proteasomal degradation of the transcription factor HBP1 (By similarity). Required for internalization of the GABA receptor GABRA1 from the cell membrane via endosomes and subsequent GABRA1 degradation (PubMed:25579817). Acts as a mediator of cell spreading and cytoskeletal responses to the extracellular matrix component THBS1 (By similarity). Homodimer; may form higher oligomers (PubMed:25579817). Identified in the CTLH complex that contains GID4, RANBP9 and/or RANBP10, MKLN1, MAEA, RMND5A (or alternatively its paralog RMND5B), GID8, ARMC8, WDR26 and YPEL5. Within this complex, MAEA, RMND5A (or alternatively its paralog RMND5B), GID8, WDR26, and RANBP9 and/or RANBP10 form the catalytic core, while GID4, MKLN1, ARMC8 and YPEL5 have ancillary roles (By similarity). Interacts with RANBP9 (By similarity). Part of a complex consisting of RANBP9, MKLN1 and GID8 (By similarity). Interacts with GABRA1 (PubMed:21482357). Interacts with the C-terminal tail of PTGER3 (PubMed:11006128). Colocalizes with GABRA1 at synapses and in postsynaptic regions. Colocalizes with actin fibers in the cell cortex. The LisH mediates head to tail dimerization.