Xu Wei, Fu Hualin, Meng Xiangyu, Sun Yiwen, Ning Fangyong, Du Zhiheng
College of Animal Sciences and Technology, Northeast Agricultural University, Harbin 150030, China.
Life (Basel). 2025 May 17;15(5):796. doi: 10.3390/life15050796.
This study aimed to clarify the sequence characteristics and spatiotemporal expression patterns of the insulin-like growth factor 1 receptor () gene in (Arctic fox), thereby addressing the existing knowledge gap regarding -mediated growth regulation in this species. The findings establish a crucial foundation for subsequent investigations into the correlation between this gene and Arctic fox growth traits. Specific primers were designed based on the cDNA sequence of the canine gene (Accession No. XM_545828). The full-length coding sequence (CDS) of the Arctic fox gene (1617 bp, encoding 538 amino acids) was successfully cloned via RT-PCR. Phylogenetic analysis using the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) algorithm revealed a 99% sequence homology in the gene between the Arctic fox and canine, confirmed their closest evolutionary relationship. Protein characterization showed that the protein has a molecular weight of 60.62 kDa (theoretical isoelectric point pI = 5.15), containing one fibronectin type-III domain and one tyrosine kinase domain, classifying it as an acidic hydrophilic transmembrane protein. Phosphorylation site prediction identified 27 phosphorylation sites, with secondary structures dominated by α-helices (26.39%) and random coils (52.79%). The gene displayed significant tissue-specific expression variations across 12 examined tissues in Arctic foxes: highest expression levels in testis, minimal expression in stomach, and no detectable expression in duodenum. Spatiotemporal expression analysis revealed that in 2-, 4-, and 6-month-old individuals, hepatic exhibited a progressive increase, testicular expression reached peak levels at 6 months, and skeletal muscle demonstrated transient upregulation peaking at 4 months. These spatiotemporal expression patterns suggest that may participate in metabolism and organ developmental processes during critical growth stages of Arctic foxes through tissue-specific regulation.
本研究旨在阐明北极狐胰岛素样生长因子1受体（IGF1R）基因的序列特征和时空表达模式，从而填补该物种中关于IGF1R介导的生长调控的现有知识空白。这些发现为后续研究该基因与北极狐生长性状之间的相关性奠定了关键基础。基于犬类IGF1R基因的cDNA序列（登录号XM_545828）设计了特异性引物。通过RT-PCR成功克隆了北极狐IGF1R基因的全长编码序列（CDS）（1617 bp，编码538个氨基酸）。使用非加权组平均法（UPGMA）算法进行的系统发育分析显示，北极狐与犬类在IGF1R基因上的序列同源性为99%，证实了它们最密切的进化关系。蛋白质特性表明，IGF1R蛋白的分子量为60.62 kDa（理论等电点pI = 5.15），包含一个III型纤连蛋白结构域和一个酪氨酸激酶结构域，将其归类为酸性亲水性跨膜蛋白。磷酸化位点预测确定了27个磷酸化位点，二级结构以α-螺旋（26.39%）和无规卷曲（52.79%）为主。IGF1R基因在北极狐12个被检测组织中表现出显著的组织特异性表达差异：在睾丸中表达水平最高，在胃中表达最低，在十二指肠中未检测到表达。时空表达分析表明，在2、4和六个月大的个体中，肝脏IGF1R呈逐渐增加趋势，睾丸表达在6个月时达到峰值，骨骼肌在4个月时出现短暂上调并达到峰值。这些时空表达模式表明，IGF1R可能通过组织特异性调节参与北极狐关键生长阶段的代谢和器官发育过程。
