Reliable reference genes for gene expression analyses under the hypomagnetic field in a migratory insect

Area of Science:

• Magnetobiology and Environmental Physiology
• Molecular Biology and Gene Expression Analysis

Background:

• The hypomagnetic field (HMF), a weakened geomagnetic field (GMF), is a valuable tool for studying magnetic field effects on biological systems.
• Accurate gene expression analysis using Reverse Transcription quantitative Polymerase Chain Reaction (RT-qPCR) relies on the selection of stable reference genes (RGs).
• Previous studies have often overlooked the critical step of validating RG stability under specific experimental conditions, such as HMF exposure.

Purpose of the Study:

• To identify and validate the most stable reference genes for RT-qPCR analysis in the brown planthopper (Nilaparvata lugens) under hypomagnetic field (HMF) conditions.
• To provide reliable genetic markers for future studies investigating the physiological and developmental effects of HMF on this migratory insect pest.
• To establish a robust methodology for reference gene selection applicable to magnetobiology research.

Main Methods:

• Expression stability of eight candidate reference genes was analyzed in Nilaparvata lugens across different developmental stages (nymphal and adult) and morphs (macropterous and brachypterous).
• Three established algorithms (BestKeeper, NormFinder, and GeNorm) were employed to evaluate gene expression stability.
• Candidate genes were assessed under both hypomagnetic field (HMF) and local geomagnetic field (GMF) conditions.

Main Results:

• Specific reference gene pairs were identified as most stable for different nymphal instars (e.g., RPL5 & α-TUB1 for 1st instar).
• Optimal reference gene sets varied for adult females and males, and between macropterous and brachypterous morphs (e.g., AK & ARF1 for adult females).
• The study successfully determined reliable reference genes crucial for accurate gene expression profiling under HMF exposure in Nilaparvata lugens.

Conclusions:

• The identified reference genes facilitate precise gene expression analysis in Nilaparvata lugens exposed to hypomagnetic fields.
• This study underscores the importance of rigorous reference gene validation for magnetobiology research, particularly when investigating magnetic field intensity.
• The findings contribute to a better understanding of organismal responses to altered magnetic environments and provide a foundation for future magnetoreception studies.