Abstract: The Kazakh horse is a highly valuable indigenous Chinese breed known for its use in both milk and meat production. However, the mechanisms underlying color variation in the abdominal adipose tissue of this breed remain poorly understood. In this study, the sequencing of non-coding RNAs (ncRNAs) was conducted on abdominal adipose tissue of different colors from Kazakh horses, with the aim of investigating the molecular mechanisms responsible for this variation. A total of 205 differentially expressed long non-coding RNAs (DELncRNAs) including , , and ; 52 differentially expressed microRNAs (DEmiRNAs) including and ; and 559 differentially expressed circular RNAs (DEcircRNAs) including and , were identified between Group W and Group Y. GO annotation and KEGG enrichment analyses of the DEGs revealed that these genes were primarily involved in biological processes such as chemical homeostasis (biological process, BP), intracellular components (cellular component, CC), and iron-sulfur cluster binding (molecular function, MF) as well as in metabolic pathways related to lipid biosynthesis and metabolism including vitamin B6 metabolism, tryptophan metabolism, and glycerolipid metabolism. The sequencing accuracy was further validated using reverse transcription quantitative PCR (RT-qPCR). This study identified key DEGs and signaling pathways associated with the color variation in adipose tissue of Kazakh horses and sheds light on the regulatory genes and biological processes involved. These findings provide a theoretical basis and research foundation for future studies on color variations in the adipose tissue of equine species.
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Overview
This study investigated the molecular mechanisms behind the color variation observed in the abdominal fat tissue of male Kazakh horses using non-coding RNA sequencing.
The research identified differentially expressed non-coding RNAs and genes associated with biological pathways that may influence adipose color differences.
Background and Importance
The Kazakh horse is a valuable Chinese breed, important for both milk and meat production.
Variation in the color of abdominal adipose (fat) tissue in these horses is common but poorly understood at the molecular level.
Understanding the mechanisms behind fat color variation is significant for genetic, physiological, and potentially economic reasons.
Research Objective
To explore the molecular differences related to the variation in color of abdominal adipose tissue in Kazakh horses.
This was done by sequencing and analyzing non-coding RNAs (ncRNAs), which are known to play regulatory roles in gene expression.
Methodology
Samples were collected from abdominal adipose tissue of two different color groups labeled Group W and Group Y.
High-throughput sequencing was performed to identify differentially expressed non-coding RNAs, including:
Long non-coding RNAs (lncRNAs) – 205 were found differentially expressed.
Circular RNAs (circRNAs) – 559 differed in expression between the groups.
Subsequent analyses were conducted on differentially expressed genes (DEGs) linked to these ncRNAs to understand their biological functions and pathways using:
Gene Ontology (GO) annotation which categorizes genes based on biological processes (BP), cellular components (CC), and molecular functions (MF).
Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment to identify relevant metabolic pathways.
Validation of sequencing results was performed using reverse transcription quantitative PCR (RT-qPCR) to confirm the accuracy of differential expression data.
Key Findings
The differentially expressed genes were primarily involved in:
Chemical homeostasis (BP)—regulation of internal chemical balance which may affect pigmentation or fat composition.
Intracellular components (CC)—indicating that variations might be linked with cellular structures.
Iron-sulfur cluster binding (MF)—a molecular function related to enzymes involved in electron transfer and metabolic processes.
Enriched metabolic pathways included:
Vitamin B6 metabolism, which can influence amino acid metabolism and pigmentation.
Tryptophan metabolism, which contributes to the synthesis of bioactive compounds.
Glycerolipid metabolism, important for fat synthesis and storage, which may affect adipose tissue characteristics.
The identification of these pathways and genes suggests regulatory roles for ncRNAs in fat color variation.
Significance and Implications
The study provides the first insights into the complex regulatory network involving non-coding RNAs that influence adipose tissue color in Kazakh horses.
The findings offer a theoretical foundation for future research into the genetic and molecular basis of fat color variation in horses and possibly other species.
This could potentially lead to genetic markers that aid in breeding programs or in enhancing meat and milk quality associated with fat composition.
Concluding Remarks
This research establishes a link between differential expression of ncRNAs and metabolic pathways associated with adipose color variation.
It highlights the significance of non-coding RNAs in phenotypic traits beyond traditional protein-coding genes.
Future studies can build on these findings to better understand fat physiology and apply this knowledge in animal breeding and health management.
Cite This Article
APA
Zhou Y, Yao X, Meng J, Wang J, Zeng Y, Li L, Ren W.
(2025).
Mechanisms of Variation in Abdominal Adipose Color Among Male Kazakh Horses Through Non-Coding RNA Sequencing.
Biology (Basel), 14(9), 1285.
https://doi.org/10.3390/biology14091285
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