Cloning, characterization, and expression analysis of the novel acetyltransferase retrogene Ard1b in the mouse.
N-alpha-terminal acetylation is a modification process that occurs cotranslationally on most eukaryotic proteins. The major enzyme responsible for this process, N-alpha-terminal acetyltransferase, is composed of the catalytic subunit ARD1A and the auxiliary subunit NAT1. We cloned, characterized, and studied the expression pattern of Ard1b (also known as Ard2), a novel homolog of the mouse Ard1a. Comparison of the genomic structures suggests that the autosomal Ard1b is a retroposed copy of the X-linked Ard1a. Expression analyses demonstrated a testis predominance of Ard1b. A reciprocal expression pattern between Ard1a and Ard1b is also observed during spermatogenesis, suggesting that Ard1b is expressed to compensate for the loss of Ard1a starting from meiosis. Both ARD1A and ARD1B can interact with NAT1 to constitute a functional N-alpha-terminal acetyltransferase in vitro. The expression of ARD1B protein can be detected in mouse testes but is delayed until the first appearance of round spermatids. In a cell culture model, the inclusion of the long 3' untranslated region of Ard1b leads to reduction of luciferase reporter activity, which implicates its role in translational repression of Ard1b during spermatogenesis. Our results suggest that ARD1B may have an important role in the later course of the spermatogenic process.
Pang
Alan Lap-Yin
AL
Laboratory of Clinical Genomics, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA. panga@mail.nih.gov
Peacock
Stephanie
S
Johnson
Warren
W
Bear
Deborah H
DH
Rennert
Owen M
OM
Chan
Wai-Yee
WY
D020413:3' Untranslated Regions; D000123:Acetyltransferases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D016466:CHO Cells; D002460:Cell Line; D003001:Cloning, Molecular; D006224:Cricetinae; D003412:Cricetulus; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D017930:Genes, Reporter; D047468:Immunoprecipitation; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008540:Meiosis; D051379:Mice; D008969:Molecular Sequence Data; D063209:N-Terminal Acetyltransferase A; D063213:N-Terminal Acetyltransferase E; D009928:Organ Specificity; D010455:Peptides / Q000276:immunology; D011485:Protein Binding; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D018626:Retroelements; D016415:Sequence Alignment; D013091:Spermatogenesis / Q000235:genetics*; D013094:Spermatozoa / Q000254:growth & development / Q000378:metabolism; D013737:Testis / Q000166:cytology* / Q000254:growth & development / Q000378:metabolism
D020413:3' Untranslated Regions; D007527:Isoenzymes; D010455:Peptides; D011993:Recombinant Fusion Proteins; D018626:Retroelements; D000123:Acetyltransferases; D063209:N-Terminal Acetyltransferase A; C508558:Naa10 protein, mouse; C545086:Naa11 protein, mouse; D063213:N-Terminal Acetyltransferase E; D001191:Arylamine N-Acetyltransferase; C089384:N-acetyltransferase 1