Zhao Chao, Liu Guangshuai, Shang Shuai, Wei Qinguo, Zhang Lei, Xia Tian, Yang Xiufeng, Sun Guolei, Zhang Honghai
College of Life Science, Qufu Normal University, Qufu, Shandong, People's Republic of China.
College of Marine Life Sciences, Ocean University of China, Qingdao, Shandong, People's Republic of China.
Genetica. 2019 Apr;147(2):141-148. doi: 10.1007/s10709-019-00057-3. Epub 2019 Mar 13.
Carnivores exhibit various fat contents and energy reserves to adapt to their environments. However, the molecular mechanisms underlying lipid metabolic differences among carnivores have not been well explored. Long-chain acyl-CoA synthetases (ACSLs) catalyze the initial step in lipid metabolism by activating fatty acids (FAs), and they drive acyl-CoAs toward anabolic lipid synthesis or catabolic β-oxidation. We identified the sequences of the genes of the ACSL family (ACSL1, ACSL3, ACSL4, ACSL5 and ACSL6) in the sable (Martes zibellina) via transcriptome sequencing. The ACSL gene sequences of 13 other carnivores were obtained from NCBI. Phylogenetic results showed that unlike the widely accepted carnivore phylogeny, Canidae and Felidae tend to group together based on ACSL4 and ACSL6. The evolutionary analyses identified a series of positively selected amino acid residues in ACSL1, ACSL4 and ACSL5. Two radical amino acid substitutions detected in sable suggested potential insights into the molecular mechanism underlying the relatively low fat content in this animal. This is the first study to investigate the molecular mechanisms underlying the adaptive evolution of fat metabolism in carnivores. Overall, the ACSL genes were under different evolutionary forces in carnivores, and some genes have undergone adaptive evolution in lipid metabolism.
食肉动物表现出各种脂肪含量和能量储备以适应其环境。然而，食肉动物之间脂质代谢差异背后的分子机制尚未得到充分探索。长链酰基辅酶A合成酶（ACSLs）通过激活脂肪酸（FAs）催化脂质代谢的第一步，并推动酰基辅酶A走向合成代谢性脂质合成或分解代谢性β-氧化。我们通过转录组测序鉴定了紫貂（Martes zibellina）中ACSL家族基因（ACSL1、ACSL3、ACSL4、ACSL5和ACSL6）的序列。其他13种食肉动物的ACSL基因序列从NCBI获得。系统发育结果表明，与广泛接受的食肉动物系统发育不同，犬科和猫科基于ACSL4和ACSL6倾向于聚集在一起。进化分析在ACSL1、ACSL4和ACSL5中鉴定出一系列正选择的氨基酸残基。在紫貂中检测到的两个激进氨基酸取代为该动物相对较低脂肪含量背后的分子机制提供了潜在的见解。这是第一项研究食肉动物脂肪代谢适应性进化背后分子机制的研究。总体而言，ACSL基因在食肉动物中受到不同的进化力量影响，一些基因在脂质代谢中经历了适应性进化。
