Component of the ribosome quality control complex (RQC), a ribosome-associated complex that mediates ubiquitination and extraction of incompletely synthesized nascent chains for proteasomal degradation (PubMed:23178123). RQC1 is essential for the recruitment of CDC48 to ribosomal subunits (PubMed:23479637). Component of the ribosome quality control complex (RQC), composed of the E3 ubiquitin ligase RKR1/LTN1, RQC1 and RQC2, as well as CDC48 and its ubiquitin-binding cofactors. RQC forms a stable complex with 60S ribosomal subunits (PubMed:23178123, PubMed:23479637). Present with 339 molecules/cell in log phase SD medium. Belongs to the TCF25 family.