Design,screening and evaluation of VEGF siRNA
- VernacularTitle:VEGF siRNA的筛选、评价及siRNA的设计规则探讨
- Author:
Chunxia JING
;
Huan ZHANG
- Publication Type:Journal Article
- Keywords:
siRNA;
vascular endothelial growth factor(VEGF);
design;
evaluation
- From:
Basic & Clinical Medicine
2006;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective Nine VEGF siRNAs were designed and their efficiencys were evaluated for introducing new and effective design rules of siRNA.Methods Nine VEGF siRNA sequences with nineteen nucleic acids were designed.After construction in vitro,VEGF siRNAs were transferred into neuroglioma cells by lipofectamine.The level of VEGF protein in the media was determined by ELISA 48 hours after transferring.The relationship between the characteristics of VEGF siRNA and its' interfering effect were analyzed.Results A quantitative parameter called H-b index were used to characterize the secondary structure of VEGF mRNA.A low value of the H-b index would mean that the structure of mRNA is loose,in which the nucleotides of the targeting region are likely to be accessible by siRNA and the effects are better.The experiments showed a negative correlation between the suppression of VEGF protein expression and H-b index(r=-0.498).The H-b indexs of siRNAs targeting VEGF mRNA 386~406 and 401~421 position were less,however the effects of suppression were better.The siRNAs conferred a strong RNAi activity with A residue at position 6 and A/U residues at position 19 of sense strand of siRNAs.Thethermodynamic properties of siRNA play a critical role in the transferring effects.The lower average of internal stability values for positions 9~14 of the antisense strand is facilitating the interfering effect.The lower binding energy is the more stable incorporation between antisense strand of siRNA and mRNA present,the more favorable is for RISC cleaving mRNA.Conclusions The sequences of VEGF siRNA have been designed successfully and effectively inhibited the expression of VEGF protein.