461425-49-0Relevant articles and documents
Synthesis of site-specifically phosphate-caged sirnas and evaluation of their RNAi activity and stability
Wu, Li,Pei, Fen,Zhang, Jinhao,Wu, Junzhou,Feng, Mengke,Wang, Yuan,Jin, Hongwei,Zhang, Liangren,Tang, Xinjing
, p. 12114 - 12122 (2014)
A complete set of new photolabile nucleoside phosphoramidites were synthesized, then site-specifically incorporated into sense or antisense strands of siRNA for phosphate caging. Single caging modification was made along siRNA strands and their photomodulation of gene silencing were examined by using the firefly luciferase reporter gene. Several key phosphate positions were then identified. Furthermore, multiple caging modifications at these key positions led to significantly enhanced photomodulation of gene silencing activity, suggesting a synergistic effect. The caging group on both the terminally phosphate-caged siRNA and the single-stranded caged RNA has comparatively high stability, whereas hydrolysis of the caged group from the internally caged siRNA was observed, irrespective of the presence of Mg2+. Molecular dynamic simulations demonstrated that enhanced hydrolysis of the caging group on internally phosphate-caged siRNAs was due to easy fragmentation of the caging group upon formation of the pentavalent intermediate of the phosphotriester with attack by water. The caging group in the terminally phosphate-caged siRNA or single-stranded caged RNA prefers to form π-π stacks with nearby nucleobases. In addition to providing explanations for previous observations, this study sheds further light on the design of caged oligonucleotides and indicates the direction of future development of nucleic acid drugs with phosphate modifications.
General method for the synthesis of caged phosphopeptides: Tools for the exploration of signal transduction pathways
Rothman, Deborah M.,Vazquez, M. Eugenio,Vogel, Elizabeth M.,Imperiali, Barbara
, p. 2865 - 2868 (2007/10/03)
(figure presented) An interassembly approach for the synthesis of peptides containing 1-(2-nitrophenyl)ethyl-caged phosphoserine, -threonine, and -tyrosine has been developed. Photochemical uncaging of these peptides releases the 2-nitrophenylethyl protecting group to afford the corresponding phosphopeptide. The peptides described herein are based on phosphorylation sites of kinases involved in cell movement or cell cycle regulation and demonstrate the versatility of the method and compatibility with the synthesis of polypeptides, including a variety of encoded amino acids.