Glutamyl tRNA Amidotransferase Subunit F (GATF)

In Bacillus subtilis, the formation of glutaminyl-tRNA is accomplished by first charging tRNA(Gln) with glutamate, which is then amidated. Glutamine was preferred over asparagine and ammonia as the amide donor in vitro. There is a functional analogy of this reaction to that catalyzed by glutamine synthetase.

However, recognizable orthologs of YGR102C (GatF) could only be found in the Kluyveromyces lactis and Candida glabrata genomes. The human genome encodes, in addition to orthologs of the gatA and gatB (PET112) genes, an ortholog of the bacterial gatC gene (gatA, gatB, gatC). Two of these gene products, GatB and GatC, like in yeast, display the sequence of a canonical MTS. Most, if not all, eukaryotes use the transamidation pathway to generate Q-_mtRNA^Q. It has been recently confirmed that this is the case in A. thaliana mitochondria.