Genome-wide identification of Diacylglycerol Acyltransferases (DGAT) family genes influencing Milk production in Buffalo

Jiajia Liu,Zhiquan Wang,Jun Li,Liguo Yang,Hui Li

doi:10.1186/s12863-020-0832-y

Abstract

BackgroundThe diacylglycerol acyltransferases (DGAT) are a vital group of enzymes in catalyzing triacylglycerol biosynthesis. DGAT genes like DGAT1 and DGAT2, have been identified as two functional candidate genes affecting milk production traits, especially for fat content in milk. Buffalo milk is famous for its excellent quality, which is rich in fat and protein content. Therefore, this study aimed to characterize DGAT family genes in buffalo and to find candidate markers or DGAT genes influencing lactation performance.ResultsWe performed a genome-wide study and identified eight DGAT genes in buffalo. All the DGAT genes classified into two distinct clades (DGAT1 and DGAT2 subfamily) based on their phylogenetic relationships and structural features. Chromosome localization displayed eight buffalo DGAT genes distributed on five chromosomes. Collinearity analysis revealed that the DGAT family genes were extensive homologous between buffalo and cattle. Afterward, we discovered genetic variants loci within the genomic regions that DGAT genes located in buffalo. Seven haplotype blocks were constructed and were associated with buffalo milk production traits. Single marker association analyses revealed four most significant single nucleotide polymorphisms (SNPs) mainly affecting milk protein percentage or milk fat yield in buffalo. Genes functional analysis indicated that these DGAT family genes could influence lactation performance in the mammal through regulating lipid metabolism.ConclusionIn the present study, we performed a comprehensive analysis for the DGAT family genes in buffalo, which including identification, structural characterization, phylogenetic classification, chromosomal distribution, collinearity analysis, association analysis, and functional analysis. These findings provide useful information for an in-depth study to determine the role of DGAT family gens play in the regulation of milk production and milk quality improvement in buffalo.

Highlights

The diacylglycerol acyltransferases (DGAT) are a vital group of enzymes in catalyzing triacylglycerol biosynthesis
Our study provided a deep insight into DGAT family genes that influence milk production traits, which is essential for future improvement of milk quality and quantity in the buffalo breeding industry
24 non-redundant protein sequences encoded by eight DGAT genes (DGATs), including DGAT1, DGAT2, DGAT2L1/MOGAT1, DGAT2L3/AWAT1, DGAT2L4/AW AT2, DGAT2L5/MOGAT2, DGAT2L7/MOGAT3, and DG AT2L6 were identified in Bubalus bubalis (Table 1)

Summary

Introduction

The diacylglycerol acyltransferases (DGAT) are a vital group of enzymes in catalyzing triacylglycerol biosynthesis. DGAT genes like DGAT1 and DGAT2, have been identified as two functional candidate genes affecting milk production traits, especially for fat content in milk. Water buffalo is the second most extensive resource of milk supply around the world, and it is well known for its high milk quality with higher fat contents compared with cattle milk (6.4–8.0% vs 4.1–5.0%) [1]. They convert the low-quality indigenous grasses into milk more efficiently than dairy cows with lower methane emissions. It’s hard to credit most of the effects to one single gene DGAT1, since the milk production traits are polygenic traits, a series of genes may be involved in the process, especially in genes belonging to the same family, which have similar sequence and likely common evolutionary origin and similar function

Objectives

Methods

Results

Discussion

Conclusion