Evaluation of Reference Genes for Transcriptional Profiling in Two Cockroach Models

Area of Science:

• Entomology
• Molecular Biology
• Genomics

Background:

• German cockroaches (B. germanica) and American cockroaches (P. americana) are significant public health pests and model organisms for hemimetabolous insects.
• Reliable gene expression analysis using quantitative real-time PCR (qPCR) requires stable reference genes, which are currently lacking for these species.
• Accurate gene expression profiling is crucial for functional genomics studies in cockroaches.

Purpose of the Study:

• To evaluate the expression stability of common insect reference genes in B. germanica and P. americana.
• To identify optimal reference genes for qPCR normalization across different tissues, developmental stages, and experimental conditions.
• To provide a resource for selecting appropriate reference genes for functional genomics in these cockroach species.

Main Methods:

• Expression levels of candidate reference genes, including actin, were analyzed in various tissues and developmental stages of B. germanica and P. americana.
• Gene expression stability was assessed using three algorithms (geNorm, BestKeeper, NormFinder) and a comprehensive program (RefFinder).
• Optimal reference genes were selected based on stability rankings under specific experimental conditions.

Main Results:

• RPL32 in B. germanica and EF1α in P. americana exhibited the lowest expression variation across all tested samples.
• RefFinder analysis identified condition-specific optimal reference genes for accurate qPCR normalization.
• A combination of RPL32 and EF1α is recommended for B. germanica, while single reference genes are preferred for P. americana.

Conclusions:

• This study establishes condition-specific reference gene recommendations for B. germanica and P. americana.
• The findings facilitate accurate gene expression profiling and advance functional genomics research in these important cockroach models.
• The identified reference genes ensure the reliability of qPCR data in entomological and public health studies.