When used in conjunction with our powerful TaqMan® Gene Expression Assays, TaqMan® Protein Assays enable an integrated real-time PCR-based approach for measuring relative changes in gene and protein expression—from the same starting sample using a single analytical platform.

Parallel Sample Preparation Workflow for Concurrent Analysis of mRNA & Protein Expression

We have validated this dual TaqMan® Assay approach using NTERA2 cells as a model system. These experiments assessed protein and mRNA expression profiles and fold-change throughout the timecourse of induction with retinoic acid (RA), for 4 stem cell pluripotency markers and 2 differentiation markers (NCAM1 and ALCAM). RA induction causes the NTERA2 cells to differentiate and develop into neuronal progenitors over the course of several weeks. NTERA2 cell lysates were prepared with the Protein Expression Sample Preparation Kit; in parallel, RNA was isolated from a portion of the samples using the Ambion® PARIS™ and TURBO DNA-free™ Kits. The samples were analyzed for target protein and mRNA transcripts using TaqMan® Assays for protein expression and gene expression, respectively. Real-time PCR was performed on a StepOnePlus™ Real-Time PCR System. The results (see figures) clearly demonstrate the power of this dual approach for correlating changes in protein expression relative to mRNA levels.

Protein Expression Analysis

TaqMan® Protein Assays detect changes in protein levels during a course of treatment with retinoic acid (RA).

Gene Expression (mRNA) Analysis

TaqMan® Gene Expression Assays analyze mRNAs that encode the proteins in the previous figure.