Multi-transcriptomics reveals RLMF axis-mediated signaling molecules associated with bovine feed efficiency.

The regulatory axis plays a vital role in interpreting the information exchange and interactions among mammal organs. In this study on feed efficiency, it was hypothesized that a rumen-liver-muscle-fat () regulatory axis exists and scrutinized the flow of energy along the axis employing consensus network analysis from a spatial transcriptomic standpoint. Based on enrichment analysis and protein-protein interaction analysis of the consensus network and tissue-specific genes, it was discovered that carbohydrate metabolism, energy metabolism, immune and inflammatory responses were likely to be the biological processes that contribute most to feed efficiency variation on the regulatory axis. In addition, clusters of genes related to the electron respiratory chain, including , clusters of genes related to fatty acid metabolism including , as well as clusters of the ribosomal-related gene including , the , and the could be the primary effector genes responsible for feed efficiency variation. The findings demonstrate that high feed efficiency cattle, through the synergistic action of the regulatory axis , may improve the efficiency of biological processes (carbohydrate metabolism, protein ubiquitination, and energy metabolism). Meanwhile, high feed efficiency cattle might enhance the ability to respond to immunity and inflammation, allowing nutrients to be efficiently distributed across these organs associated with digestion and absorption, energy-producing, and energy-storing organs. Elucidating the distribution of nutrients on the regulatory axis could facilitate an understanding of feed efficiency variation and achieve the study on its molecular regulation.