MicroRNAs (miRNAs) are known to take part in different biological mechanisms, including biotic as well as abiotic cellular stresses. The present investigation was aimed to identify comparative expression profile of differentially expressed miRNAs among Sahiwal (Bos indicus) and Frieswal (Bos indicus × Bos taurus) cattle breeds during summer stress. Stress responses in animals were characterized by recording various physiological parameters, biochemical assays and expression profiling of heat shock protein 70 (Hsp70) during elevated environmental temperature. Ion Torrent-based deep sequencing as well as CLC-genomic analysis identified 322 and 420 Bos taurus annotated miRNAs among Sahiwal and Frieswal, respectively. A total 69 common miRNAs were identified to be differentially expressed during summer among the breeds. Out of the 69, a total 14 differentially expressed miRNAs viz. bta-mir 6536-2, bta-mir-2898, bta-mir-let-7b, bta-mir-425, bta-mir-2332, bta-mir-2478, bta-mir-150, bta-mir142, bta-mir-16a, bta-mir-2311, bta-mir-1839, bta-mir-1248-1, bta-mir-103-2 and bta-mir-181b were randomly selected for qRT-PCR-based validation. bta-mir-2898, bta-mir-6536-1, bta-mir-let-7b, bta-mir-2478, bta-mir-150, bta-mir-16a, bta-mir-2311, bta-mir-1032-b and bta-mir-181-b were significantly (p < 0.01) upregulated during summer among Frieswal in comparison to Sahiwal while, bta-mir 6536-2, bta-mir-2332, bta-mir142, bta-mir-1839 and bta-mir-1248-1 was significantly (p < 0.01) expressed at higher level in Sahiwal in contrast to Frieswal correlation coefficient analysis revealed that bta-mir(s)-150, 16a and 181b are negatively correlated (p < 0.05) with Hsp70 expression. Thus, this study identified that miRNA expression during summer stress can vary between the breeds which may reflect their differential post-transcriptional regulation.

已知 MicroRNA (miRNA) 参与不同的生物学机制，包括生物和非生物细胞应激。本研究旨在确定夏季胁迫期间Sahiwal ( Bos indicus ) 和 Frieswal ( Bos indicus × Bos taurus ) 牛品种之间差异表达 miRNA 的比较表达谱。动物的应激反应通​​过在环境温度升高期间记录各种生理参数、生化测定和热休克蛋白 70 (Hsp70) 的表达谱来表征。基于 Ion Torrent 的深度测序以及 CLC 基因组分析确定了 322 和 420 Bos taurus分别在 Sahiwal 和 Frieswal 中注释了 miRNA。共有 69 种常见的 miRNA 在夏季期间被鉴定为不同品种之间的差异表达。在这 69 个中，共有 14 个差异表达的 miRNA，即。bta-mir 6536-2、bta-mir-2898、bta-mir-let-7b、bta-mir-425、bta-mir-2332、bta-mir-2478、bta-mir-150、bta-mir142、bta随机选择-mir-16a、bta-mir-2311、bta-mir-1839、bta-mir-1248-1、bta-mir-103-2 和 bta-mir-181b 用于基于 qRT-PCR 的验证。bta-mir-2898、bta-mir-6536-1、bta-mir-let-7b、bta-mir-2478、bta-mir-150、bta-mir-16a、bta-mir-2311、bta-mir-与 Sahiwal 相比，Frieswal 的 1032-b 和 bta-mir-181-b 在夏季显着上调 ( p  < 0.01)，而 bta-mir 6536-2、bta-mir-2332、bta-mir142、bta-mir- 1839 和 bta-mir-1248-1 显着 (p  < 0.01) 在 Sahiwal 中以较高水平表达，与 Frieswal 相关系数分析相反，显示 bta-mir(s)-150、16a 和 181b 与 Hsp70 表达呈负相关 ( p < 0.05)。因此，本研究发现，夏季应激期间 miRNA 的表达可能因品种而异，这可能反映了它们不同的转录后调控。