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bioRxiv · 10.1101/2025.02.14.638312

Mediator-29 Limits Caenorhabditis elegans Fecundity

Pocock, R.·Fan, Q.·Tran, C.·Cao, W.
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Abstract

Mediator is an evolutionarily conserved multiprotein complex that acts as a critical coregulator of RNA polymerase II-mediated transcription. While core Mediator components are broadly required for transcription, others govern specific regulatory modules and signalling pathways. Here, we investigated the function of MDT-29/MED29 in the Caenorhabditis elegans germ line. We found that endogenously-tagged MDT-29 is ubiquitously expressed and concentrated in discrete foci within germ cell nuclei. Functionally, depleting MDT-29 in the germ line during larval development boosted fecundity. We determined that the increase in progeny production was likely caused by a combination of an expanded germline stem cell pool and decreased germ cell apoptosis. Thus, MDT-29 may act to optimize specific gene expression programs to control distinct germ cell behaviors, providing flexibility to progeny production in certain environments.

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Pocock, R., Fan, Q., Tran, C., Cao, W.. 2025-02-19. Mediator-29 Limits Caenorhabditis elegans Fecundity. https://doi.org/10.1101/2025.02.14.638312

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