# Unveiling the Regulatory Mechanism of Tibetan Pigs Adipogenesis Mediated by WNT16: From Differential Phenotypes to the Application of Multi-Omics Approaches

## TL;DR

This study explores how WNT16 regulates fat development in Tibetan pigs, offering new ways to improve meat quality without excessive fat.

## Contribution

The study identifies WNT16 as a key regulator of site-specific fat deposition in Tibetan pigs using a multi-omics approach.

## Key findings

- IMF adipocytes are smaller and contain more monounsaturated fatty acids than other fat types.
- WNT16 inhibition reduces lipid accumulation and downregulates adipogenic regulators in preadipocytes.
- Integrated omics analysis links WNT16 and L-tyrosine to the melanogenesis pathway in fat regulation.

## Abstract

This study unveils the regulatory role of WNT16 in adipogenesis in Tibetan pigs through phenotypic detection, multi-omics analysis, and gene function validation. The research found that intramuscular fat cells have significantly smaller areas and diameters compared to other fat types and contain higher levels of monounsaturated fatty acids. Transcriptomic and metabolomic analyses identified differential expression of WNT16 and L-tyrosine, both involved in the melanogenesis pathway. Functional validation showed that inhibiting WNT16 reduces lipid droplet accumulation and downregulates adipogenic regulators. This study provides new targets for optimizing meat quality, which is significant for the sustainable development of the pig industry and improving pork quality.

The aim of this study is to investigate the physiological characteristics and regulatory mechanisms of porcine intramuscular fat (IMF), subcutaneous fat (take back fat (BF), for example), and visceral fat (take perienteric fat (PF), for example) to address the challenge of optimizing meat quality without excessive fat deposition. Many improved breed pigs have fast growth rates, high lean meat rates, and low subcutaneous fat deposits, but they also have low IMF content, resulting in poor meat quality. There is usually a positive correlation between intramuscular fat and subcutaneous fat deposits. This study selected eight-month-old female Tibetan pigs as experimental subjects. After slaughter, fat samples were collected. Histological differences in adipocyte morphology were observed via hematoxylin–eosin (HE) staining of tissue sections, and phenotypic characteristics of different adipose tissues were analyzed through fatty acid composition determination. Transcriptome sequencing and untargeted metabolomics were employed to perform pairwise comparisons between different fatty tissues to identify differentially expressed genes and metabolites. A siRNA interference model was constructed and combined with Oil Red O staining and lipid droplet optical density measurement to investigate the regulatory role of WNT16 in adipocyte differentiation. Comparative analysis of phenotypic and fatty acid composition differences in adipocytes from different locations revealed that IMF adipocytes have significantly smaller areas and diameters compared to other fat depots and contain higher levels of monounsaturated fatty acids. Integrated transcriptomic and metabolomic analyses identified differential expression of WNT16 and L-tyrosine, both of which are involved in the melanogenesis pathway. Functional validation showed that inhibiting WNT16 in porcine preadipocytes downregulated adipogenic regulators and reduced lipid droplet accumulation. This cross-level regulatory mechanism of “phenotype detection–multi-omics analysis–gene function research” highlighted WNT16 as a potential key regulator of site-specific fat deposition, providing new molecular targets for optimizing meat quality through nutritional regulation and genetic modification.