Acts as a linker between gene transcription and histone H2B monoubiquitination at 'Lys-120' (H2BK120ub1) ref. Interacts with the RNA polymerase II transcriptional machinery via its WW domain and with RNF20-RNF40 via its coiled coil region, thereby linking and regulating H2BK120ub1 and gene transcription ref. Regulates the cell-cycle checkpoint activation in response to DNA damage ref. Positive regulator of amino acid starvation-induced autophagy ref. Also acts as a negative regulator of basal autophagy ref. Positively regulates MTOR activity by promoting, in an energy-dependent manner, the assembly of the TTT complex composed of TELO2, TTI1 and TTI2 and the RUVBL complex composed of RUVBL1 and RUVBL2 into the TTT-RUVBL complex. This leads to the dimerization of the mTORC1 complex and its subsequent activation ref. May negatively regulate the ubiquitin proteasome pathway ref.