Asgardian

Functional class 2 CCA-adding enzymes in Asgard archaea and their implications for eukaryogenesis

CCA-adding enzymes are essential for transfer RNA (tRNA) maturation and translation among all domains of life. A long standing dogma holds that archaea encode exclusively class one CCA-adding enzymes (CCA1), whereas bacteria and eukaryotes encode class two enzymes (CCA2), creating a perceived strict evolutionary separation between archaeal and eukaryotic CCA adding enzymes. Here, we show that this view is incorrect.