Component of the 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. The complex is probably involved in the transfer of the threonylcarbamoyl moiety of threonylcarbamoyl-AMP (TC-AMP) to the N6 group of A37. Pcc1 functions as a dimerization module for the complex. Component of the KEOPS complex that consists of Kae1, Bud32, Cgi121 and Pcc1; the whole complex dimerizes. Belongs to the CTAG/PCC1 family. Truncated N-terminus.