Intramuscular fat (IMF) deposition is a physiological process in cattle and is highly variable among breeds suggesting
a large influence of genetic factors besides environmental factors. In order to elucidate molecular pathways
underlying the genetic variation in this trait we compared transcriptomes of Musculus longissimus dorsi
(MLD) in steers of Japanese Black and Holstein Friesian cattle breeds fed a high energy diet typically applied in
Japan to achieve maximum IMF content. We identified a total of 569 differentially expressed genes (DEGs)
with the majority (433) up-regulated in Japanese Black cattle. This breed is characterized by an extreme capacity
for IMF deposition. Subsequent Ingenuity Pathway Analysis (IPA) revealed a gene network linking parameters of
cellmorphology and maintenancewith lipidmetabolism. The data fromthis studywere deposited in NCBI'sGene
Expression Omnibus and are accessible through GEO Series accession number GSE75348. We provide here a
dataset which is of potential value to dissect molecular pathways influencing differences in fat deposition
under high-energy nutrition.