MicroRNA (miRNA) are small regulatory RNA molecules that are implicated in regulating and controlling a wide range of physiological processes including cell division, differentiation, migration, apoptosis, morphogenesis, and organogenesis. The aim of this study was to determine the expression pattern of 32 miRNA and 18 miRNA processing machinery genes during somite formation in quail embryos. The embryos were collected at stages HH (Hamburger and Hamilton) 4, 6, and 9 of embryo development (19, 24, and 30 h of incubation, respectively). Total RNA including miRNA was isolated from 4 groups of embryos (each group consisting of 6 to 8 embryos) were collected at each of the 3 stages (19, 24, and 30 h). The expression pattern of candidate miRNA and miRNA processing machinery genes was performed using quantitative real-time PCR. The results demonstrated that 7 miRNA (let-7a, mir-122, mir-125b, mir-10b, P < 0.01; let-7b, mir-26a, and mir-126, P < 0.05) were differentially expressed during early quail embryo development. In addition, the expression profile of 18 miRNA processing machinery genes was not significantly increased at 30 h of incubation compared with both 19 and 24 h. Our results suggest that machinery genes for miRNA biogenetic pathways are functional, and hence, miRNA may be involved in the regulation of early quail development. These 7 differentially expressed miRNA are suggested to play critical roles in quail embryo somite formation.
MicroRNAs (miRNA) are small regulatory RNA molecules that are implicated in regulating and controlling a wide range of physiological processes including cell division, differentiation, migration, apoptosis, morphogenesis, and organogenesis. The aim of this study was to determine the expression pattern of 32 miRNAs and 18 miRNA processing machinery genes during somite formation in quail embryos. The embryos were collected at stages HH (Hamburger and Hamilton) 4, 6 and 9 of embryo development (19, 24 and 30h of incubation, respectively). Total RNA including miRNA was isolated from four groups of embryos (each group consisting of 6-8 embryos) were collected at each of the three stages (19 h, 24 h and 30 h). The expression pattern of candidate miRNAs and miRNA processing machinery genes was performed using quantitative Real-Time polymerase chain reaction (qPCR). The results demonstrated that 7 miRNAs (let-7a, mir-122, mir-125b, mir-10b, P < 0.01; let-7b, mir-26a and mir-126, P < 0.05) were differentially expressed during early quail embryo development. In addition the expression profile of 18 miRNA processing machinery genes was not significantly increased at 30 h of incubation compared to both 19 and 24 h. Our results suggest that machinery genes for miRNAs biogenetic pathways are functional and hence, miRNAs may be involved in the regulation of early quail development. These seven differentially expressed miRNAs are suggested to play critical roles in quail embryo somite formation.