META RNA profiling: Multiplexed quantitation of targeted RNAs across large numbers of samples

META RNA profiling is a simple and inexpensive method to measure the expression of multiple targeted RNAs across many samples. By assigning sample-specific tags up-front during reverse-transcription, cDNAs from multiple samples can be pooled prior to amplification and deep sequencing. Such early parallelization of samples simplifies the workflow, minimizes cross-sample experimental variability, and reduces reagent and sequencing costs. Herein we describe the theoretical framework of the method and provide a detailed protocol to facilitate its implementation.