Hypothalamic transcriptome analysis reveals male-specific differences in molecular pathways related to oxidative...

Area of Science:

• Animal Genetics
• Molecular Biology
• Physiology

Background:

• The hypothalamus regulates feeding and adiposity, crucial for understanding lean vs. fatty pig breed differences.
• Early-life hypothalamic development influences long-term productive traits in livestock.

Purpose of the Study:

• To compare the hypothalamic transcriptome of pure Iberian (IBxIB) and Large White x Iberian (IBxLW) crossbred piglets at 60 days old.
• To identify gene expression patterns influenced by breed, sex, and their interactions in the hypothalamus.

Main Methods:

• RNA sequencing was used to analyze the hypothalamic transcriptome of IBxIB and IBxLW piglets.
• Differential gene expression analysis was performed to identify genes affected by genotype and sex.

Main Results:

• Significant differences in hypothalamic gene expression were observed between genotypes (51 DEGs) and genders (10 DEGs).
• Breed-genotype effects were more pronounced in males, with 158 DEGs compared to 31 in females.
• Male IBxIB piglets showed higher expression of mitochondrial activity genes (e.g., ND3, ND4, ND5, UQCRC2, ATP6), indicating increased oxidative phosphorylation and ROS/nitric oxide production.
• Male IBxLW piglets exhibited higher expression of the mitochondrial regulator SIRT3.
• Females showed fewer sex-specific differences, primarily related to the tricarboxylic acid cycle.

Conclusions:

• Breed and sex significantly interact to shape the hypothalamic transcriptome in young piglets.
• These early-life transcriptomic differences may underlie variations in feeding behavior and adiposity between pig breeds.