FAQ: What is the difference between the NEBNext Ultra Directional RNA library prep kit for Illumina (NEB# E7420) and the NEBNext Ultra RNA library prep kit for Illumina (NEB# E7530)?

The NEBNext Directional RNA library prep workflow preserves information about RNA strand orientation while the NEBNext Ultra RNA library prep does not. The NEBNext Ultra Directional RNA library prep contains dUTP in the second strand synthesis reaction that allows labeling of the second strand cDNA. This is followed by excision of the Us with USER enzyme, with the result that only the first strand is incorporated into the library, thereby providing the strandedness of the library. This is shown here.