InterPro domain: IPR030700

Arginine-tRNA-protein transferase catalyses the post-translational conjugation of arginine to the N terminus of a protein. In eukaryotes, this functions as part of the N-end rule pathway of protein degradation by conjugating a destabilising amino acid to the N-terminal aspartate or glutamate of a protein, targeting the protein for ubiquitin-dependent proteolysis [ 1 ]. In Saccharomyces cerevisiae, Cys20, 23, 94 and/or 95 are thought to be important for activity [ 2 ]. Of these, only Cys 94 appears to be completely conserved in this family.

This entry represents a family of aminoacyl-transferases that includes prokaryotic aspartate/glutamate leucyltransferase, and eukaryotic arginine-tRNA-protein transferase.

Aspartate/glutamate leucyltransferase (also known as bacterial protein transferase or Bpt) functions in the N-end rule pathway of protein degradation where it conjugates Leu from its aminoacyl-tRNA to the N-termini of proteins containing an N-terminal aspartate or glutamate. This protein shows sequence similarity to the eukaryotic N-end rule pathway component arginyl-transferase Ate1 [ 3 ].

1. Alternative splicing results in differential expression, activity, and localization of the two forms of arginyl-tRNA-protein transferase, a component of the N-end rule pathway. Mol. Cell. Biol. 19, 182-93
2. Binding of phenylarsenoxide to Arg-tRNA protein transferase is independent of vicinal thiols. Biochemistry 34, 15829-37
3. Aminoacyl-transferases and the N-end rule pathway of prokaryotic/eukaryotic specificity in a human pathogen. Proc. Natl. Acad. Sci. U.S.A. 103, 3078-83