Fabrication of siRNA microarrays for the high-throughput analysis of gene functions

RNA interference has emerged as a powerful tool for post-transcriptional gene silencing, and therefore, has been employed for the analysis of gene functions at a cellular level. In this study, we fabricated microarrays that allowed parallel transfection of short interfering RNAs (siRNAs). A micropatterned monolayer of alkanethiols was used as a platform for loading siRNA in an array format. Endoribonuclease-digested dsRNAs were prepared by using EGFP cDNA as a template and loaded onto the microarray taking advantage of electrolyte complex formation with a cationic lipid. It was demonstrated that, when HEK293 cells were cultured directly on the siRNA-loaded microarray, the expression of co-transfected EGFP gene was significantly reduced specifically on the microspots in a dose-dependent manner.