学術論文|脳梗塞検査|株式会社アミンファーマ研究所

[2013-11] Hayashi et al., Biochem. Biophys. Res. Commun. 441, 999-1004 (2013)

Polyamines, putrescine, spermidine (SPD), and spermine are closely linked to cell growth, and highly regulate the levels of transcription, translation and protein turnover. We propose that SPD stimulates the formation of Ile-tRNAIle by inducing a selective structural change of the G-G mismatch containing acceptor stem in tRNAIle. Here, we provide insight into how SPD recognizes and stabilizes the G-G mismatch containing acceptor stem in tRNAIle with molecular modeling (MM), density functional theory (DFT) calculations, and molecular dynamics (MD) simulations. The results of the MM and DFT calculations indicate that the negatively charged region of the G-G mismatch containing acceptor stem in tRNAIle is preferentially recognized by positively charged SPD. In addition, MD simulations indicate that all of the positively charged amino groups of SPD under physiological conditions (N1(NH3+), N5(NH2+), and N10(NH3+) could form hydrogen bonds with tRNAIle and trigger the SPD-induced stabilization and structural change of the G-G mismatch containing acceptor stem in tRNAIle. Thus, this approach should be useful for determining the preferential binding site and appropriate binding mode of polyamines on tRNAIle.