A novel Xenopus acetyltransferase with a dynamic expression in early development

We have isolated a novel acetyltransferase from Xenopus laevis, named Xat-1. Xat-1 cDNA encodes a predicted protein of 846 amino acids that contains tetratricopeptide repeat (TPR) domains mediating protein-protein interactions and a bipartite nuclear localization signal (NLS). Its apparent molecular mass of 98.8 kDa was determined by SDS-PAGE analysis of Xat-1 recombinant protein in vitro translated in rabbit reticulocyte lysate. Xat-1 is homologous to N-terminal acetyltransferase 1 (NAT1), a gene that was originally discovered in yeast. Furthermore, it has many orthologs from human, mouse, Drosophila, C. elegans, and even Arabidopsis, thereby suggesting that these constitute a novel acetyltransferase family whose functions have been not examined. Xat-1 transcripts are expressed at relatively constant levels throughout early embryonic stages. They also exhibit dynamic expression pattern in brain, somites, branchial arches, pronephros, and otic vesicles. (C) 2001 Academic Press.