Spermidine does not act as an acetyl sink even when treated with high-dose.
A, relative areas of acetyl polyamines in mock and cts-1 RNAi embryos with CE-TOF/MS (data are mean ± S.E.; n = 3; *, p < 0.05). B, structural formula of acetylated spermidines, N1-acetylspermidine (top), N8-acetylspermidine (middle), and N1,N8-diacetylspermidine (bottom). C–E, the levels of acetylated spermidines, (C) N1-acetylspermidine, (D) N8-acetylspermidine, and (E) N1,N8-diacetylspermidine, in mock RNAi embryos with vehicle (−), cts-1 RNAi embryos with vehicle (−), mock RNAi embryos with Spd (+), and cts-1 RNAi embryos with Spd (+) with LC-MS/MS. The y axis values indicate each acetylspermidine level relative to that of cts-1 RNAi embryos treated with Spd (data are mean ± S.E.; n = 4; N.D., not detected; N.S., not significant).