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bioRxiv · 10.64898/2026.10.06.756944

Phosphorylation of Z granule components regulates germ granule organization and RNAi inheritance

Pshanichnaya, L.·Brehm, M.·Mikicic, I.·Hellmann, S.·Aaquib, M.·Beli, P.·Falk, S.·Ketting, R. F.
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Abstract

Small RNAs represent important carriers of epigenetic information in nematodes, and factors involved in their biogenesis reside within perinuclear germ granules. Among these condensates, Z granules are essential for the inheritance of RNA interference (RNAi). The mechanisms by which Z granules form and promote this process remain unclear. We show that Casein kinase I alpha (KIN-19) is present in Z granules and associated with DEPS-1 and HERD-1 phosphorylation. In the absence of DEPS-1 and HERD-1 phosphorylation, animals have enlarged Z granules and enhanced RNAi inheritance. We propose that DEPS-1 acts as a phosphorylation-regulated scaffold that bridges ZNFX-1 and HERD-1 proteins. Our study demonstrates that Casein kinase I alpha-mediated phosphorylation is an important factor in germ granule modulation and RNAi inheritance, and additionally provides a novel molecular scaffold for understanding germ granule complexity in C. elegans.

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Pshanichnaya, L., Brehm, M., Mikicic, I., Hellmann, S., Aaquib, M., Beli, P., Falk, S., Ketting, R. F.. 2026-10-06. Phosphorylation of Z granule components regulates germ granule organization and RNAi inheritance. https://doi.org/10.64898/2026.10.06.756944

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