Developmental alterations in DNA methylation during gametogenesis from primordial germ cells to sperm

Summary

Because epigenetics is a critical component for gene expression, the hypothesis was tested that DNA methylation alterations are dynamic and continually change throughout gametogenesis to generate the mature sperm. Developmental alterations and stage-specific DNA methylation during gametogenesis from primordial germ cells (PGCs) to mature sperm are investigated. Individual developmental stage germ cells were isolated and analyzed for differential DNA methylation regions (DMRs). The number of DMRs was highest in the first three comparisons with mature PGCs, prospermatogonia, and spermatogonia. The most statistically significant DMRs were present at all stages of development and had variations involving both increases or decreases in DNA methylation. DMR-associated genes were identified and correlated with gene functional categories, pathways, and cellular processes. Observations identified a dynamic cascade of epigenetic changes during development that is dramatic during the early developmental stages. Complex epigenetic alterations are required to regulate genome biology and gene expression during gametogenesis.

Graphical abstract

Highlights

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  A dynamic cascade of epigenetic change throughout gametogenesis from PGC to sperm

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  Most dramatic epigenetic alterations in PGC and spermatogenic stem cell stages

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  Different DNA methylation regions between and within stages were identified

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  Complex epigenetic alterations required for gene expression during gametogenesis

Abstract

Epigenetics; Stem cells research; Developmental biology