Structure and function of human Naa60 (NatF), a Golgi-localized bi-functional acetyltransferase
Chen, J.Y., Liu, L., Cao, C.L., Li, M.J., Tan, K., Yang, X., Yun, C.H.(2016) Sci Rep 6: 31425-31425
- PubMed: 27550639 
- DOI: https://doi.org/10.1038/srep31425
- Primary Citation of Related Structures:  
5HGZ, 5HH0, 5HH1 - PubMed Abstract: 
N-terminal acetylation (Nt-acetylation), carried out by N-terminal acetyltransferases (NATs), is a conserved and primary modification of nascent peptide chains. Naa60 (also named NatF) is a recently identified NAT found only in multicellular eukaryotes. This protein was shown to locate on the Golgi apparatus and mainly catalyze the Nt-acetylation of transmembrane proteins, and it also harbors lysine N(ε)-acetyltransferase (KAT) activity to catalyze the acetylation of lysine ε-amine. Here, we report the crystal structures of human Naa60 (hNaa60) in complex with Acetyl-Coenzyme A (Ac-CoA) or Coenzyme A (CoA). The hNaa60 protein contains an amphipathic helix following its GNAT domain that may contribute to Golgi localization of hNaa60, and the β7-β8 hairpin adopted different conformations in the hNaa60(1-242) and hNaa60(1-199) crystal structures. Remarkably, we found that the side-chain of Phe 34 can influence the position of the coenzyme, indicating a new regulatory mechanism involving enzyme, co-factor and substrates interactions. Moreover, structural comparison and biochemical studies indicated that Tyr 97 and His 138 are key residues for catalytic reaction and that a non-conserved β3-β4 long loop participates in the regulation of hNaa60 activity.
Organizational Affiliation: 
Department of Biophysics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing 100191, P. R. China.