Metilasyondan Pluripotensiye Erken Embriyo Gelişiminde Epigenetik Programlama

Year 2026, Volume: 15 Issue: 1, 68 - 74, 28.02.2026

Zehra Manav Yiğit , Lamiya Mardan Hacızade , Mustafa Altan , Metin Çalışkan , Gökay Bozkurt , Nazlı Can

https://doi.org/10.53424/balikesirsbd.1737294

https://izlik.org/JA58PH35WT

Abstract

Amaç: Erken embriyonik gelişim, pluripotensi ve farklılaşmayı düzenleyen transkripsiyonel ve epigenetik mekanizmalar tarafından koordine edilir. Bu çalışma, sıçan modelinde implantasyon öncesi dönemde önemli transkripsiyon faktörlerinin (Oct-3/-4, Sox-2, Nanog, SSEA-1 ve c-Myc) ve DNA metilasyon enzimlerinin (Dnmt1 ve Dnmt3) aşama spesifik ekspresyonunu araştırmayı amaçlamıştır. Gereç ve Yöntem: Embriyolar 2-8 hücre, 8-16 hücre ve blastosist aşamalarında toplandı. Gen ekspresyon düzeyleri gerçek zamanlı PCR kullanılarak değerlendirilirken, protein lokalizasyonu immünofloresan boyama ile değerlendirildi. Bulgular: Oct-3/-4 ve Sox-2, 2-8 hücre aşamasında en yüksek ekspresyon seviyelerine ulaştı, bu da bu faktörlerin erken aşamada pluripotansiyetin korunmasında önemli bir rol oynadığını göstermektedir. Nanog, c-Myc ve Dnmt3’in, blastosist aşamasında önemli ölçüde ifade düzeyi arttı, bu da bu faktörlerin soy belirlemede rol oynadığını göstermektedir. Dnmt-1, tüm aşamalarda tutarlı bir şekilde eksprese edildi, bu da epigenetik hafızadaki rolünü desteklemektedir. SSEA-1 gen ekspresyonu ile protein tespiti arasındaki tutarsızlıklar, transkripsiyon sonrası regülasyonu düşündürmektedir. Sonuç: Çalışma, transkripsiyon faktörlerinin ve DNA metilasyonunun embriyonik gelişimde önemli roller oynadığını göstermektedir. Dnmt-1'in tüm aşamalarda sürekli varlığı, embriyo gelişiminde sürekli bir epigenetik etki olduğunu göstermektedir. Bu bulgular, erken embriyonik gen regülasyonu hakkında bilgi sağlar ve gelişimsel bozukluklar üzerine gelecekteki araştırmalarda yararlı olabilir.

Keywords

DNA metilasyonu , Embriyonik gelişim , Pluripotent , Polimeraz zincir reaksiyonu , Transkripsiyon faktörleri

From Methylation to Pluripotency: Epigenetic Programming in Early Embryo Development

https://izlik.org/JA58PH35WT

Abstract

Objective: Early embryonic development is orchestrated by transcriptional and epigenetic mechanisms that regulate pluripotency and differentiation. This study aimed to investigate the stage-specific expression of key transcription factors (Oct-3/-4, Sox-2, Nanog, SSEA-1, and c-Myc) and DNA methylation enzymes (Dnmt1 and Dnmt3) during the pre-implantation period in a rat model. Materials and Methods: Embryos were collected at the 2-8 cell, 8-16 cell, and blastocyst stages. Gene expression levels were assessed using real-time PCR, while protein localisation was evaluated via immunofluorescence staining. Results: Oct-3/-4 and Sox-2 exhibited the highest levels of expression at the 2–8 cell stage, which suggests that they play an important role in the maintenance of pluripotency at an early stage. Nanog, c-Myc, and Dnmt3 were significantly upregulated at the blastocyst stage, indicating their involvement in lineage commitment. Dnmt-1 was consistently expressed across all stages, which supports its role in epigenetic memory. Discrepancies between SSEA-1 gene expression and protein detection suggested post-transcriptional regulation. Conclusion: These findings emphasise the dynamic and coordinated functions of transcriptional and epigenetic regulators during the early stages of embryogenesis. Combined mRNA and protein analysis provides a comprehensive molecular profile that is relevant to reproductive medicine and developmental biology.

Keywords

DNA methylation , Embryonic development , Pluripotent , Polymerase Chain Reaction , Transcription factors

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