ELOVL gene family plays a virtual role in response to breeding selection and lipid deposition in different tissues in chicken (Gallus gallus)

Abstract

Background Elongases of very long chain fatty acids (ELOVLs), a family of first rate-limiting enzymes in the synthesis of long-chain fatty acids, play an essential role in the biosynthesis of complex lipids. Disrupting any of ELOVLs affects normal growth and development in mammals. Genetic variations in ELOVLs are associated with backfat or intramuscular fatty acid composition in livestock. However, the effects of ELOVL gene family on breeding selection and lipid deposition in different tissues are still unknown in chickens. Results Genetic variation patterns and genetic associations analysis showed that the genetic variations of ELOVL genes were contributed to breeding selection of commercial varieties in chicken, and 14 SNPs in ELOVL2-6 were associated with body weight, carcass or fat deposition traits. Especially, one SNP rs17631638T > C in the promoter of ELOVL3 was associated with intramuscular fat content (IMF), and its allele frequency was significantly higher in native and layer breeds compared to that in commercial broiler breeds. Quantitative real-time PCR (qRT-PCR) determined that the ELOVL3 expressions in pectoralis were affected by the genotypes of rs17631638T > C. In addition, the transcription levels of ELOVL genes except ELOVL5 were regulated by estrogen in chicken liver and hypothalamus with different regulatory pathways. The expression levels of ELOVL1-6 in hypothalamus, liver, abdominal fat and pectoralis were correlated with abdominal fat weight, abdominal fat percentage, liver lipid content and IMF. Noteworthily, expression of ELOVL3 in pectoralis was highly positively correlated with IMF and glycerophospholipid molecules, including phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol and phospholipids inositol, rich in ω-3 and ω-6 long-chain unsaturated fatty acids, suggesting ELOVL3 could contribute to intramuscular fat deposition by increasing the proportion of long-chain unsaturated glycerophospholipid molecules in pectoralis. Conclusions In summary, we demonstrated the genetic contribution of ELOVL gene family to breeding selection for specialized varieties, and revealed the expression regulation of ELOVL genes and their potential roles in regulating lipid deposition in different tissues. This study provides new insights into understanding the functions of ELOVL family on avian growth and lipid deposition in different tissues and the genetic variation in ELOVL3 may aid the marker-assisted selection of meat quality in chicken.

Whole-genome selection signature differences between Chaohu and Ji’an red ducks

“…According to Liu et al, ELOVL1 is a member of a gene family responsible for the synthesis of polyunsaturated fatty acids in chickens [ 43 ]. Wang et al demonstrated that the expression of ELOVL1 – 6 in different chicken organs is closely related to fat deposition and is negatively regulated by estrogen [ 44 ].…”

Weighted gene co-expression network analysis identified hub genes critical to fatty acid composition in Gushi chicken breast muscle

“…It catalyzes the conversion of C18:00 fatty acyl-CoA to C20 and C22 fatty acids in the pathway of fatty acid synthesis [ 33 ]. Previous studies have shown that ELOVL1 is upregulated during chicken preadipocyte differentiation, suggesting its important role in the accumulation of lipid droplets in chicken adipocytes [ 34 ]. Furthermore, CPT1A catalyzes the transfer reaction between long-chain fatty acids and carnitine, facilitating the transport of fatty acids into mitochondria for fatty acid oxidation and energy production [ 35 , 36 ].…”

Genomic Insights into Molecular Regulation Mechanisms of Intramuscular Fat Deposition in Chicken

“…XM_419585) were significantly associated with pectoral muscle percentage (p < 0.05), and the AA (G7518A) genotype and GG (C7542G) genotype had the highest IMF content, highest pectoral muscle weight, and lower abdominal fat weight (AFW) and abdominal fat percentage (AFP) [35]. demonstrated that the SNP rs17631638T>C in the ELOVL3 promoter was significantly correlated with IMF through affecting its expression, and ELOVL3 may promote fat deposition in muscles by increasing the proportion of long-chain unsaturated glycerol phospholipid molecules in the breast muscle [36]. Wang et al (2023) found that C12315T, a synonymous mutation in the lipoprotein lipase (LPL) gene (XM_015280414.2), was significantly positively correlated with IMF in the pectoral and leg muscles of Baicheng-You chicken and San-huang chickens [37].…”