Heart development is a complex process regulated by multi-layered genetic as well epigenetic regulators many of which are still unknown. Besides their critical role during cardiac development, these molecular regulators emerge as key modulators of cardiovascular pathologies, where fetal cardiac genes' re-expression is witnessed. MicroRNAs have recently emerged as a crucial part of signalling cascade in both development and diseases. We aimed to identify, validate, and perform functional annotation of putative novel miRNAs using chicken as a cardiac development model system. Novel miRNAs were obtained through deep sequencing of small RNAs extracted from chicken embryonic cardiac tissue of different developmental stages. After filtering out real pre-miRNAs, their expression analysis, potential target gene's prediction and functional annotations were performed. Expression analysis revealed that miRNAs were differentially expressed during different developmental stages of chicken heart. The expression of selected putative novel miRNAs was further validated by real-time PCR. Our analysis indicated the presence of novel cardiac miRNAs that might be regulating critical cardiac development events such as cardiac cell growth, differentiation, cardiac action potential generation and signal transduction.

中文翻译：

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Gallus gallus domesticus 发育中的胎儿心脏中新型 MicroRNA 的差异表达暗示了其在心脏发育中的作用。

进行了预测和功能注释。表达分析表明，miRNA在鸡心的不同发育阶段存在差异表达。通过实时 PCR 进一步验证了选定的推定新 miRNA 的表达。我们的分析表明存在可能调节关键心脏发育事件的新心脏 miRNA，例如心脏细胞生长、分化、心脏动作电位产生和信号转导。