Updated project metadata. The Kae1/KaeA protein is a subunit of the highly evolutionarily conserved KEOPS complex (Kinase, Endopeptidase and Other Proteins of Small size). The Kae1/KaeA gene has been identified in all previously sequenced genomes of Archea, Bacteria and Eucaryota, except for the most reduced genomes. The KEOPS complex participates in the universal modification of the tRNA converting adenosine A37 to N6-threonylcarbamoyl adenosine (t6A37). This modification of A37, immediately 3’ of anticodons decoding ANN codons, is one of the few tRNA modifications present in all organisms and plays an extremely important role in the accuracy of the translation process. We characterized two mutations in kaeA of filamentous fungus Aspergillus nidulans that result in the derepression of arginine catabolic enzymes and also showed that kaeA is involved in the regulation of several other genes that control various domains of cellular metabolism. This suggests that kaeA has additional function apart from t6A37 modification. To support this hypothesis we looked for proteins interacting with KaeA.