Histone and N-terminal acetyltransferases play important roles in female reproduction and embryogenesis of the red flour beetle Tribolium castaneum

Histone acetyltransferases (HATs) catalyse the addition of acetyl groups to histones and other proteins. In contrast, histone deacetylases remove acetyl groups from core histones, and the activity of these enzymes maintains the acetylation levels of these proteins. Histone acetylation levels influence chromatin accessibility and gene expression and regulate many biological processes, including development and reproduction. Recent reports suggest that some N-terminal acetyltransferases (NATs) also regulate gene expression. We identified 29 HAT and NAT genes in the red flour beetle, Tribolium castaneum, and studied their functions in female reproduction using RNA interference (RNAi). Knockdown of seven out of 13 HAT genes (N-acetyltransferase ESCO2) (ESCO1/2), Elongator complex protein 3 (ELP3), Histone acetyltransferase type B catalytic subunit 1 (HAT1), Transcription initiation factor TFIID subunit 1 (TAF1), Protein x-mas-2 (MCM3AP), Histone acetyltransferase Tip60 (KAT5), and Cysteine-rich protein 2-binding protein (KAT14) and 12 out of 16 NAT genes Probable glucosamine 6-phosphate N-acetyltransferase (GNPNAT1), N-alpha-acetyltransferase 10 (NAA10), N-alpha-acetyltransferase 20 (NAA20), N-alpha-acetyltransferase 30 (NAA30), N-alpha-acetyltransferase 40 (NAA40), N-alpha-acetyltransferase 60 (NAA60), N-acetyltransferase 6 (NAA80), RNA cytidine acetyltransferase (NAT10), Diamine acetyltransferase 2 (SATL1), N(alpha)-acetyltransferase 16 (NAA16), Phagocyte signalling-impaired protein (NAA25), N(alpha)-acetyltransferase 35 (NAA35) caused a significant reduction in eggs laid by females compared to the eggs laid by control females injected with dsGFP. Also, knockdown of nine (KAT5, ATAT1, ELP3, HAT1, KAT8A, NAA10, NAA20, GNPNAT1 and TAF1) HAT/NAT genes caused a significant decrease in egg hatching. Parental RNAi of ATAT1 and KAT8 blocked embryogenesis. These data suggest that the acetylation of proteins plays an important role in female reproduction and embryogenesis.