Investigation of the Effects of Pre-Incubation Formaldehyde Exposure on DNA Methyltransferase (DNMT) mRNA Expression in Muscle and Liver Tissues of Chicken Embryos

Abstract

The DNA methyltransferase (DNMT) family is a group of enzymes that play an important role in epigenetic gene control and regulate the DNA methylation process. While DNMT3A and DNMT3B are responsible for establishing new methylation patterns, DNMT1 maintains existing ones. These enzymes play an active role during embryonic development, and their expression levels are markedly reduced in differentiated cells. This study aimed to determine the effects of pre-incubation formaldehyde (FA) treatment on the expression levels of DNA methyltransferase (DNMT) genes in liver and muscle tissues of chicken embryos. Fertilized chicken eggs were disinfected with FA, and liver and muscle tissues were collected from embryos on day 18 of incubation. DNMT1, DNMT3A, and DNMT3B gene expression levels were assessed using the RT-qPCR method. The results indicated that FA treatment significantly increased DNMT1 gene expression in liver tissue (p<0.05) and induced a non-significant upward trend in DNMT3A and DNMT3B gene expression. Conversely, DNMT3A gene expression significantly decreased in muscle tissue (p<0.05), while non-significant downward trends were observed for DNMT1 and DNMT3B genes. These findings suggest that formaldehyde treatment differentially modulates DNMT gene expression in chicken embryos in a tissue-specific and gene-specific manner, potentially influencing epigenetic mechanisms.

Keywords

• Gene expression
• DNMT genes
• Fumigation
• Chick embryo

Tavuk Embriyolarında Kuluçka Öncesi Formaldehit Uygulamasının Kas ve Karaciğer Dokularında DNA Metiltransferaz (DNMT) mRNA Ekspresyonu Üzerine Etkilerinin Araştırılması

Abstract

DNA metiltransferaz (DNMT) ailesi, epigenetik gen kontrolünde önemli rol oynayan, DNA metilasyon sürecini düzenleyen enzim grubudur. DNMT3A ve DNMT3B yeni metilasyon desenleri oluştururken, DNMT1 var olan desenleri korumaktan sorumludur. Bu enzimler embriyonal gelişimde aktif rol oynar ve farklılaşma sonrası hücrelerde ekspresyon seviyeleri büyük ölçüde azalır. Bu çalışma, tavuk embriyolarına kuluçka öncesi uygulanan formaldehitin (FA), karaciğer ve kas dokularında DNMT genlerinin ekspresyon düzeyleri üzerindeki etkilerini belirlemek amacıyla gerçekleştirilmiştir. Araştırmada, döllü tavuk yumurtaları FA ile dezenfekte edilmiş ve kuluçkanın 18. gününde embriyolardan karaciğer ve kas dokuları alınarak DNMT1, DNMT3A ve DNMT3B genlerinin ekspresyon seviyeleri qRT-PCR yöntemiyle araştırılmıştır. Sonuçlar, FA uygulamasının karaciğer dokusunda DNMT1 gen ekspresyonunu anlamlı düzeyde artırdığını (p<0.05), DNMT3A ve DNMT3B genlerinde ise anlamlı olmayan bir artış eğilimi oluşturduğunu göstermiştir. Aksine, kas dokusunda DNMT3A geninin ekspresyonu anlamlı düzeyde azalırken (p<0.05), DNMT1 ve DNMT3B genlerinde anlamlı olmayan azalma eğilimleri gözlenmiştir. Elde edilen bulgular, formaldehit uygulamasının tavuk embriyolarında DNMT genlerinin ekspresyonunu dokuya özgü ve gen bazında farklı şekillerde etkileyerek, epigenetik mekanizmaları modüle edebileceğini ortaya koymuştur.

Keywords

• Gen ekspresyonu
• DNMT genleri
• Fumigasyon
• Civciv embriyo

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