Aspartyl tRNA Synthetase (DARS)

DARS charges its cognate tRNA with aspartate during protein biosynthesis.The predicted DARS protein has 500 amino acids and a calculated molecular mass of 57,000 Da. The human DARS protein has 95% amino acid identity with rat Dars and shares unevenly distributed identity with yeast aspartyl-tRNA synthetase, with 69% identity at the C-terminal half and 46% identity at the N-terminal half. The authors discussed several potential functional domains in the DAR protein, including a region of conserved lysine residues which is also found in bacterial and yeast synthetases and is likely to be the binding site for the 3-prime end of tRNA, a nucleotide triphosphate-binding motif, an ATP-binding motif with strong similarity to that present in E. coli alanyl-tRNA synthetase, and a cyclic AMP-dependent protein kinase phosphorylation site.