College of Animal Science and Technology, Northwest A&F University, Shaanxi Key Laboratory of Animal Genetics, Breeding and Reproduction, Yangling, Shaanxi, China.
Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark.
Vet Med Sci. 2020 Aug;6(3):399-409. doi: 10.1002/vms3.251. Epub 2020 Mar 5.
Max dimerization protein 3 (MXD3) belongs to the MYC superfamily of basic helix-loop-helix leucine zipper transcription factors, and MXD3-MAX heterodimers can bind to promoters of target genes to modulate their expression. The aim of this study was to determine the MXD3 mRNA expression levels in various cattle tissues comprising heart, liver, spleen, lung, kidney, Longissimus dorsi muscle and subcutaneous fat in Chinese Qinchuan and Xianan cattle breeds. The RT-qPCR data showed that the MXD3 gene was variably expressed between all tissues and at levels that were significantly different between two breeds (p < .05). We used the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method to investigate the possible association between single-nucleotide polymorphisms (SNP) within the MXD3 gene and five different growth traits in cattle. We found two intronic SNPs (g.2694 C>T and g.3801 T>C) and one SNP in 3'untranslated region (3'UTR) (g.6263 G>A) of MXD3 gene. Association analysis revealed strong associations between pairwise and triple SNP combinations and the growth traits. Based on these results, we suggest that MXD3 polymorphisms could be useful as molecular markers in the Chinese beef cattle breeding program.
最大二聚化蛋白 3（MXD3）属于 MYC 超家族碱性螺旋-环-螺旋亮氨酸拉链转录因子，MXD3-MAX 异二聚体可以与靶基因的启动子结合，调节其表达。本研究旨在测定中国秦川牛和西安牛两个品种牛的心脏、肝脏、脾脏、肺、肾脏、背最长肌和皮下脂肪等各种组织中 MXD3 mRNA 的表达水平。RT-qPCR 数据显示，MXD3 基因在所有组织中均有差异表达，且在两个品种之间的表达水平存在显著差异（p<.05）。我们使用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法研究了 MXD3 基因内单核苷酸多态性（SNP）与牛的五个不同生长性状之间的可能关联。我们发现了 MXD3 基因内含子中的两个 SNP（g.2694 C>T 和 g.3801 T>C）和一个 3'非翻译区（3'UTR）中的 SNP（g.6263 G>A）。关联分析显示，成对和三对 SNP 组合与生长性状之间存在强烈关联。基于这些结果，我们认为 MXD3 多态性可用作中国肉牛育种计划中的分子标记。
