# An Integrated Multi-Omics Study of Mammalian Skeletal, Cardiac, and Smooth Muscles

## TL;DR

This study explores molecular differences in skeletal, cardiac, and smooth muscles using multi-omics data from pigs and mice, identifying tissue-specific genes and metabolites.

## Contribution

The study reveals conserved molecular profiles and novel genes/metabolites specific to each muscle type, offering new research targets.

## Key findings

- 207 genes, including LRRC2 and PPP1R14C, were found enriched in striated muscle.
- 14 fast-twitch and 6 slow-twitch fiber-enriched metabolites were identified in skeletal muscle.
- 10-Deacetylbaccatin III was highly enriched in fast-twitch fibers, suggesting a new research target.

## Abstract

Muscle tissue, as a major tissue type, is classified by its structure and function into smooth, cardiac, and skeletal muscle. However, comprehensive studies on the evolutionary conservation of molecular differences among these three muscle tissues have been limited. In this study, we employed pigs and mice as models to perform multi-omics profiling (transcriptome, proteome, and metabolome) of these three muscle tissues in order to define their molecular landscapes. Furthermore, we characterized skeletal muscle metabolic heterogeneity. We identified 207 genes enriched in striated muscle, including poorly characterized genes such as LRRC2 and PPP1R14C. Distinct sets of genes and metabolites, conserved between the two species, were specifically enriched in each tissue: skeletal muscle (121 genes and 6 metabolites), cardiac muscle (57 genes and no specific metabolites), and smooth muscle (349 genes and 11 metabolites). Notably, the currently unannotated gene LRRC20 was most enriched in skeletal muscle, followed by cardiac muscle, and showed negligible expression in smooth muscle, suggesting its potential as a functional research target. Within skeletal muscle, 14 fast-twitch and 6 slow-twitch fiber-enriched metabolites were identified. In particular, 10-Deacetylbaccatin III was enriched in skeletal muscle and, more specifically, highly enriched in fast-twitch fibers, marking it as a promising and novel research target. These results provide a resource for research in both medicine and agricultural science.