Preservation of gene expression ratios among multiple complex cDNAs after PCR amplification: application to...

Area of Science:

• Molecular Biology
• Genomics
• Biotechnology

Background:

• Comparative gene expression studies are frequently hindered by limited tissue availability and poor messenger RNA (mRNA) quality.
• Collective polymerase chain reaction (PCR) amplification offers a promising solution for minute mRNA quantities.

Purpose of the Study:

• To systematically evaluate the impact of PCR amplification on the relative abundance of specific mRNAs in complex complementary DNA (cDNA) preparations.
• To validate the utility of PCR-amplified cDNA for differential gene expression studies.

Main Methods:

• Comparison of specific mRNA relative abundance in complex cDNA from tissue and cell cultures before and after PCR amplification.
• Systematic analysis of concentration ratios among different cDNA preparations post-amplification.

Main Results:

• PCR amplification unpredictably alters the absolute abundance of individual mRNAs within a cDNA library.
• Crucially, concentration ratios of specific mRNAs between different cDNA preparations are consistently conserved after PCR amplification.

Conclusions:

• PCR-amplified cDNA is as effective as unamplified cDNA for comparative gene expression studies involving specific mRNAs.
• PCR amplification overcomes challenges with limited biological materials for differential screening techniques like gene chip and array analyses without compromising data quality.