Journal de médecine légale

Distinct DNA Methylation Patterns Found in Chicken Lampbrush Chromosomes

Abstract

Alla Veniamin

Playing a pivotal role in transcription and replication control, developmental reprogramming, retroelement silencing, and various other genomic activities, DNA methylation is an essential epigenetic regulatory mechanism. In the context of mammalian development, the establishment of a specific DNA methylation pattern in germ cells is a prerequisite for embryonic development. However, our understanding of DNA methylation in germ cells of other animals remains limited. To address this gap in knowledge, we conducted a comprehensive analysis of the single-cell methylome of chicken diplotene oocytes. Through the development of a methylation-based segmentation approach for the chicken genome, we identified methylated gene promoters exclusive to oocytes. This extensive characterization of methylation patterns in these cells revealed that they closely mirror the chromosomal distribution observed in somatic tissues, despite the presence of a distinct transcriptionally hyperactive genome architecture in chicken diplotene oocytes. Our findings shed light on the intricate role of DNA methylation in these cells.