Department of Animal Genetics and Breeding, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Mohanpur, Nadia, West Bengal, 741252, India.
Division of Livestock and Fishery Management, ICAR-Research Complex for Eastern Region, Patna, Bihar, 800014, India.
Cell Stress Chaperones. 2020 Mar;25(2):317-326. doi: 10.1007/s12192-020-01075-3. Epub 2020 Feb 4.
The present study was undertaken to investigate genetic variability in a fragment comprising 5'UTR along with partial coding sequence of Hsp70 gene and its association with thermotolerance traits in Murrah buffalo at ICAR-Research Complex for Eastern Region, Patna (India). The allelic variants were identified from genomic DNA samples using SSCP technique. The PCR products were sequenced and analyzed. Data on different thermotolerance traits recorded in three seasons were analyzed by least squares ANOVA taking the SSCP genotypes as fixed effect. Two allelic variants (A and B), each of 503-bp in size, were documented with frequency of 0.59 and 0.41, respectively, and three genotypes (AA, AB and BB) with corresponding frequency of 0.30, 0.58 and 0.12. The allelic variants were due to single nucleotide substitution at 55th base position leading to a change of threonine (A) to methionine (B) in amino acid sequence. Both the allelic variants had 99.8% similarity in nucleotide sequence. In phylogenetic tree, allele A was in a cluster while allele B and Gangatiri cattle sequence formed a different cluster. The SSCP genotypes had significant effect on different thermotolerance traits in summer with thermo-humidity index of ≥ 84. Buffaloes with AA genotype had the highest (P ˂ 0.05) summer evening rectal temperature, respiration rate and pulse rate, inferring that the buffaloes carrying AA genotype had more stress in summer than those with AB and BB genotype. These SSCP genotypes might have differential role in heat shock protein response to induce thermotolerance of Murrah buffaloes in Gangetic plains.
本研究旨在调查印度比哈尔邦农业研究理事会东部地区卡里卡特拉研究综合体的摩拉水牛 HSP70 基因 5'UTR 及其部分编码序列片段的遗传变异及其与耐热性性状的关系。使用 SSCP 技术从基因组 DNA 样本中鉴定等位基因变异。对 PCR 产物进行测序和分析。以 SSCP 基因型为固定效应，采用最小二乘方差分析（ANOVA）分析三个季节记录的不同耐热性性状的数据。记录到两种等位基因变异（A 和 B），大小分别为 503bp，频率分别为 0.59 和 0.41，以及三种基因型（AA、AB 和 BB），频率分别为 0.30、0.58 和 0.12。等位基因变异是由于第 55 个碱基位置的单个核苷酸取代导致氨基酸序列中苏氨酸（A）变为蛋氨酸（B）。两个等位基因变异在核苷酸序列上有 99.8%的相似性。在系统发育树中，等位基因 A 位于一个聚类中，而等位基因 B 和 Gangatiri 牛序列形成了一个不同的聚类。SSCP 基因型对夏季不同耐热性性状有显著影响，夏季热湿指数≥84。AA 基因型的水牛夏季傍晚直肠温度、呼吸率和脉搏率最高（P<0.05），表明携带 AA 基因型的水牛在夏季比 AB 和 BB 基因型的水牛承受更大的压力。这些 SSCP 基因型可能在热休克蛋白反应中发挥不同的作用，从而诱导恒河平原的摩拉水牛产生耐热性。
