# Functional Differentiation Reconfiguration in the Midgut of Nezara viridula (Hemiptera: Pentatomidae) Based on Transcriptomics: Multilayer Enrichment Analysis and Topological Network Interpretation

## TL;DR

This study explores how the midgut of the stinkbug Nezara viridula adapts to a maize diet, revealing specialized functions in different gut regions and potential targets for pest control.

## Contribution

The study introduces a 'metabolism–defense–regeneration' regulatory model and identifies key genes for pest control using transcriptomic analysis.

## Key findings

- Each midgut region (M1, M2, M3) shows unique gene expression related to metabolism, defense, and regeneration.
- Neuroreceptor and metabolic enzyme genes show parallel expression patterns in the same midgut segments.
- The findings establish a framework for analyzing complex biological systems and developing pest control strategies.

## Abstract

Employing a systematic bioinformatics approach, this investigation elucidates the functional specialization mechanism formed in the midgut of Nezara viridula during adaptation to a maize-based diet, revealing a “metabolism–defense–regeneration” regulatory system with fine-grained functional compartmentalization. The research demonstrates significant functional differentiation among distinct midgut regions (M1, M2, M3): M1 primarily governs nutrient metabolism and detoxification and M2 emphasizes cell communication and immune defense, while M3 regulates cell renewal. Particularly noteworthy are the parallel enrichment patterns of neuro-metabolic pathways and the discovery of differentially expressed genes (such as TACR, HTR, GLA, NAGA), which provide novel insights into understanding insect dietary evolution, while the identified key genes offer potential targets for pest control. These achievements not only deepen the comprehension of insect digestive physiology but also establish a theoretical foundation for developing green management strategies against agricultural pests.

The present investigation systematically elucidates the distinct functional specialization within the M1–M3 midgut sections of the significant agricultural pest, Nezara viridula. Employing an integrated transcriptomic analysis, three pivotal discoveries were achieved: (1) each midgut segment possesses unique gene expression signatures; (2) metabolic and signal transduction pathways exhibit coordinated regulatory patterns; and (3) parallel expression changes occur between neuroreceptor (e.g., TACR/HTR) and metabolic enzyme (e.g., GLA/NAGA) genes within identical midgut segments. These data reveal that the M1 region is primarily enriched in metabolic processes and neural signaling; the M2 region emphasizes cellular junctions and immune responses, while the M3 region is mainly responsible for cellular senescence and renewal. These discoveries advance the understanding of feeding adaptation mechanisms in Hemipteran insects and propose a “metabolism–defense–regeneration” functional model for the midgut. The established multi-level analytical framework provides a robust methodology for subsequent dissection of complex biological systems, identification of key molecular targets for functional validation, and for the development of novel pest control strategies.