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Characterization of hARD2, a processed hARD1 gene duplicate, encoding a human protein N-alpha-acetyltransferase.

ABSTRACT: BACKGROUND:Protein acetylation is increasingly recognized as an important mechanism regulating a variety of cellular functions. Several human protein acetyltransferases have been characterized, most of them catalyzing epsilon-acetylation of histones and transcription factors. We recently described the human protein acetyltransferase hARD1 (human Arrest Defective 1). hARD1 interacts with NATH (N-Acetyl Transferase Human) forming a complex expressing protein N-terminal alpha-acetylation activity. RESULTS:We here describe a human protein, hARD2, with 81 % sequence identity to hARD1. The gene encoding hARD2 most likely originates from a eutherian mammal specific retrotransposition event. hARD2 mRNA and protein are expressed in several human cell lines. Immunoprecipitation experiments show that hARD2 protein potentially interacts with NATH, suggesting that hARD2-NATH complexes may be responsible for protein N-alpha-acetylation in human cells. In NB4 cells undergoing retinoic acid mediated differentiation, the level of endogenous hARD1 and NATH protein decreases while the level of hARD2 protein is stable. CONCLUSION:A human protein N-alpha-acetyltransferase is herein described. ARD2 potentially complements the functions of ARD1, adding more flexibility and complexity to protein N-alpha-acetylation in human cells as compared to lower organisms which only have one ARD.

SUBMITTER: Arnesen T

PROVIDER: S-EPMC1475586 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

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Characterization of hARD2, a processed hARD1 gene duplicate, encoding a human protein N-alpha-acetyltransferase.

Arnesen Thomas T Betts Matthew J MJ Pendino Frédéric F Liberles David A DA Anderson Dave D Caro Jaime J Kong Xianguo X Varhaug Jan E JE Lillehaug Johan R JR

BMC biochemistry 20060425

<h4>Background</h4>Protein acetylation is increasingly recognized as an important mechanism regulating a variety of cellular functions. Several human protein acetyltransferases have been characterized, most of them catalyzing epsilon-acetylation of histones and transcription factors. We recently described the human protein acetyltransferase hARD1 (human Arrest Defective 1). hARD1 interacts with NATH (N-Acetyl Transferase Human) forming a complex expressing protein N-terminal alpha-acetylation ac ...[more]

PMID: 16638120

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Dataset Information

Characterization of hARD2, a processed hARD1 gene duplicate, encoding a human protein N-alpha-acetyltransferase.

Publications

Characterization of hARD2, a processed hARD1 gene duplicate, encoding a human protein N-alpha-acetyltransferase.

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