Gene expression study of key regulators of germ layer formation in chicken embryos using RT-PCR technique

Document Type : Research Paper

Authors

1 Assistant professor, College of Veterinary Medicine, University of Basra, Basra, Iraq

2 Assistant professor, College of Veterinary Medicine, University of Basra, Basra, Iraq.

3 Assistant Lecture, College of Veterinary Medicine, University of Basra, Basra, Iraq.

Abstract

Objective
Various studies have shown that the PRDM14 gene plays a very important and fundamental role in the early development of the chicken embryo and the formation of the germ layer. The aim of this study was to investigate the expression pattern of the PRDM14 gene in early embryogenesis and also to investigate its evolutionary role. This work also seeks to simplify the identification of major transcription factor families active in the first five days of development.

Materials and methods
For comparison of PRDM14 and other members of the PRDM family, we used a phylogenetic analysis. Comparative expression profiling was also conducted to track gene activity during stages E1-E5, which represent the earliest and most sensitive phases of chicken embryonic development. Public genomic datasets and annotated gene families were used to identify transcription factors and determine their distribution across the genome.

Results
The analysis showed that PRDM14 and other PRDM family genes follow an evolutionary divergence pattern similar to that of other vertebrates. The stages E1-E5 were identified as the most crucial in embryogenesis, showing major shifts in gene expression. Among the studied chicken embryos, 1097 transcription factors were observed. These genes did not have random distribution, but they have significant genomic structure pattern. Transcription factor families such as bHLH, Zf-C2H2, and Homeobox were also detected in this study. They play important role in early development. 60 amino acids make up Homeobox proteins. These proteins are essential for regulating many developmental processes. ISL1, MKX, NANOG, and CDX2 are key transcription factors identified and classified into the Homeobox and bHLH groups. These factors are involved in cell fate determination, somatic lineage formation, and pluripotency. At days 4 and 5, the bHLH group of transcription factors showed high expression. These factors were found to play an important and essential role in the nervous system and germ cell development.

Conclusion
This study shows that the early stages of embryogenesis involve coordinated activity of major transcription factor families. The structured expression pattern and early activation of PRDM14 suggest its essential role in guiding cell identity and developmental pathways in chicken embryos.

Keywords

References

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Agricultural Biotechnology Journal
Volume 18, Issue 1
January 2026
Pages 241-258

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