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bioRxiv · 10.1101/2024.12.03.626448

A female-specific RdDM-associated element guides de novo DNA methylation during rice gametophyte development

Kim, T.·Resende, M. F.·Zhao, M.·Begcy, K.
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Abstract

DNA methylation is crucial for regulating gene expression and silencing transposons. While the spatiotemporal specificity of DNA methylation controls organ formation and development, the molecular mechanisms underlying locus- or tissue-specific DNA methylation remain unclear. Previously, locus- or tissue-specific DNA methylation was thought to depend solely on the recognition of histone methylations. Here we show that high expression of 24-nucleotide small interfering RNAs (24-nt siRNAs) leads to incremental CHH methylation at specific loci via the RNA-directed DNA methylation (RdDM) pathway during female gametophyte development in rice. We also identify a DNA motif, the Female-specific RdDM-associated Element (FRE), which guides methylation to these loci. Furthermore, we show that the female-preferentially expressed protein OsCLSY3 directly interacts with FRE to regulate CHH methylation specifically in female reproductive tissues. These findings uncover a novel molecular mechanism necessary for tissue- and locus-specific de novo DNA methylation that might be conserved across diverse organisms including animals.

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Kim, T., Resende, M. F., Zhao, M., Begcy, K.. 2024-12-04. A female-specific RdDM-associated element guides de novo DNA methylation during rice gametophyte development. https://doi.org/10.1101/2024.12.03.626448

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