Freshness is an important index to determine the quality deterioration (protein degradation and changes in appearance) of chilled chicken meat and is a primary consideration of consumers. Adenosine monophosphate deaminase 1 (AMPD1) catalyzes the deamination of adenosine monophosphate to inosine monophosphate in skeletal muscle and is the rate‐limiting step in the purine nucleotide cycle. Inosine monophosphate is regarded as an important indicator of meat freshness in chicken. This study investigated the association of polymorphisms in the chicken AMPD1 promoter region with meat freshness during freezing storage. An SNP (c. –905G>A) was found to be associated with the freshness (K‐value) of chicken breast meat. Chickens with the AA genotype had significantly lower K‐values than those with GG and AG genotypes (P < 0.01). Individuals with the AA genotype also had higher breast meat AMPD1 mRNA levels than did those with the GG and AG genotypes (P < 0.01, P < 0.05). A luciferase assay revealed that genotype AA had greater transcriptional activity than genotype GG. Transcription factor binding site analysis identified distinct putative transcription factor binding sites in the two alleles of mutation site c. –905. In summary, we identified an SNP (c. –905G>A) in the promoter region of the AMPD1 gene that may modulate the binding affinity of different transcription factors to control AMPD1 expression and affect the freshness K‐value of chicken meat.

中文翻译：

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AMPD1启动子区域的功能性突变影响鸡的启动子活性和胸肉新鲜度

新鲜度是确定冷藏鸡肉质量下降（蛋白质降解和外观变化）的重要指标，并且是消费者的主要考虑因素。腺苷单磷酸脱氨酶1（AMPD1）催化骨骼肌中腺苷单磷酸脱氨为肌苷单磷酸，是嘌呤核苷酸循环中的限速步骤。肌苷一磷酸被认为是鸡肉中肉类新鲜度的重要指标。这项研究调查了鸡AMPD1启动子区域中的多态性与冷冻储存过程中肉类新鲜度的关系。发现SNP（c。–905G> A）与鸡肉的新鲜度（K值）有关。AA基因型的鸡的K值明显降低值比具有GG和AG基因型的那些值（P  <0.01）。具有AA基因型的个体也具有比具有GG和AG基因型的个体更高的胸肉AMPD1 mRNA水平（P  <0.01，P  <0.05）。荧光素酶测定法显示，AA型基因比GG型具有更高的转录活性。转录因子结合位点分析确定了突变位点c的两个等位基因中不同的推定转录因子结合位点。–905。总而言之，我们在AMPD1基因的启动子区域鉴定出一个SNP（c。–905G> A），该SNP可以调节不同转录因子的结合亲和力来控制AMPD1的表达并影响新鲜度K。鸡肉的价值。