Component of the EKC/KEOPS complex that is required for the formation of a threonylcarbamoyl group on adenosine at position 37 (t(6)A37) in tRNAs that read codons beginning with adenine (PubMed:22912744, PubMed:28805828). The complex is probably involved in the transfer of the threonylcarbamoyl moiety of threonylcarbamoyl-AMP (TC-AMP) to the N6 group of A37 (PubMed:22912744, PubMed:28805828). TPRKB acts as an allosteric effector that regulates the t(6)A activity of the complex. TPRKB is not required for tRNA modification (PubMed:22912744, PubMed:28805828). Component of the EKC/KEOPS complex composed of at least GON7, TP53RK, TPRKB, OSGEP and LAGE3; the whole complex dimerizes (PubMed:22912744, PubMed:28805828). Interacts with TP53RK/PRPK (PubMed:12659830). Widely expressed. The disease is caused by variants affecting the gene represented in this entry. Belongs to the CGI121/TPRKB family.