Reference gene selection and evaluation for expression analysis using qRT-PCR in Galeruca daurica (Joannis)

Area of Science:

• Molecular Biology
• Entomology
• Genomics

Background:

• Quantitative real-time PCR (qRT-PCR) is vital for gene expression analysis.
• Accurate normalization requires stable reference genes, especially in diverse experimental conditions.
• Reference gene validation is essential for reliable results in insect studies.

Purpose of the Study:

• To assess the stability of eight commonly used reference genes in Galeruca daurica.
• To identify optimal reference genes for qRT-PCR normalization under various experimental conditions.
• To provide a standardized procedure for reference gene selection in insect functional genomics.

Main Methods:

• Quantitative real-time PCR (qRT-PCR) was performed on Galeruca daurica samples.
• Eight candidate reference genes were evaluated across different developmental stages, sexes, tissues, and conditions (diapause/non-diapause).
• Gene expression stability was analyzed using geNorm, Normfinder, BestKeeper, comparative ΔC t method, and RefFinder.

Main Results:

• Succinate dehydrogenase (SDHA) and tubulin-alpha (TUB-α) were optimal for temperature-treated larvae and different tissues in adults.
• Ribosomal protein L32, SDHA, and glutathione S-transferase were best for all developmental stages.
• ACT and TUB-α were suitable for male and female adults; SDHA and TUB-α were stable in diapause and non-diapause adults.

Conclusions:

• Reference gene stability varies significantly with experimental conditions in Galeruca daurica.
• Custom selection and validation of reference genes are critical for accurate qRT-PCR analysis in insects.
• The findings offer a standardized approach for gene expression studies in insects.