c("transfected construct: GFP", "knock-down: Xrn1 shRNA")
c("transfected construct: GFP-SOX", "knock-down: Xrn1 shRNA")
c("transfected construct: GFP-SOX", "knock-down: Xrn1 siRNA")
c("transfected construct: GFP", "knock-down: Xrn1 siRNA")