Definition: RNA spike-in is RNA transcripts of known sequence and quantity used to calibrate measurements in RNA hybridization assays, such as microarray experiments, RT-qPCR, and RNA-Seq
With the advent of microarray and the commercialization of high-throughput methods for sequencing and RNA detection assays, positive control oligonucleotides are necessary to provide a standard of target sequence concentration. RNA spike-in controls can provide a measure of sensitivity and specificity of RNA-Seq experiment.
Origin: mimic eukaryotic RNAs or C. elegans RNA mimic.
Usage: A known quantity of RNA spike-in is mixed with the experiment sample during preparation, used as a normalization control for RNA expression profiling. Many researchers choose to spike a synthetic RNA into their RNA prep to monitor RNA recovery and reverse transcription efficiency.
ERCC RNA Spike-In Mix, ThermoFisher #4456740.
92 transcripts designed to be 250-2000 nt in length.
ExiSEQ NGS Spike-in kit -- small RNA/microRNA, ExIQEN #800100.
52 synthetic 5' phosphorylated microrNAs of different concentrations.
miRNeasy Serum/Plasma Spike-In Control (QIAGEN), a C. elegans miR-39 miRNA mimic.
Customized RNA mimics.