Identification of Novel lncRNAs Differentially Expressed in Placentas of Chinese Ningqiang Pony and Yili Horse Breeds.
Authors: Pu Yabin, Zhang Yanli, Zhang Tian, Han Jianlin, Ma Yuehui, Liu Xuexue
Journal: Animals : an open access journal from MDPI
Summary
# Editorial Summary Placental function fundamentally shapes fetal growth and development in horses, with long non-coding RNAs (lncRNAs) emerging as important regulators of growth-related traits, yet their specific roles in equine placental biology had not been characterised. Researchers used RNA sequencing on placentas from two Chinese horse breeds with markedly different mature sizes—the diminutive Ningqiang pony (withers height <106 cm) and the larger Yili horse (≈148 cm)—to identify and compare lncRNA expression profiles, generating 813 million high-quality reads and cataloguing 1464 distinct placental lncRNAs. Analysis revealed 107 differentially expressed lncRNAs between breeds, with 68 upregulated in the larger Yili horses; crucially, these DELs targeted genes including TBX3, EDN3, and TGFB1 that are known to regulate limb development, myoblast differentiation, and embryonic growth. The discovery that multiple lncRNAs regulate TBX3—a gene previously associated with small body size in other pony breeds—provides molecular evidence that placental lncRNA expression patterns may underpin breed-specific size differences and suggests that placental development could be an overlooked but significant factor influencing growth potential in foals. For equine professionals involved in breeding decisions or managing growth in young horses, these findings highlight that fetal growth outcomes depend not simply on mare nutrition or individual genetic variants, but on the complex regulatory architecture of placental gene expression.
Read the full abstract on PubMed
Practical Takeaways
- •Placental lncRNA expression patterns differ significantly between horse breeds and may explain some heritable variation in body size and growth
- •Understanding placental gene regulation could inform breeding decisions and selection for desired body size traits in horse populations
- •TBX3 and related developmental genes represent potential molecular markers for predicting fetal growth potential in different horse breeds
Key Findings
- •RNA-seq analysis identified 1464 placental lncRNAs in horse placentas, with 107 differentially expressed between Ningqiang (small pony) and Yili (large) breeds
- •68 lncRNAs were upregulated and 39 downregulated in the larger Yili breed compared to Ningqiang
- •Six target genes (TBX3, CACNA1F, EDN3, KAT5, ZNF281, TMED2) linked to limb development and skeletal myoblast differentiation were identified as potential regulators of body size
- •Two DELs targeting TBX3 gene suggest placental lncRNAs may regulate horse body size through developmental pathways