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bioRxiv · 10.1101/2025.10.22.683991

Loss of the distal-proximal GLP-1/Notch activation gradient in the aging C. elegans germline

van Vuuren, R. J. J.·Narbonne, P.·Martel, P.-O.
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Abstract

In C. elegans hermaphrodites, the distal tip cells (DTCs) capping the distal gonad arms provide the niche signal, a Notch ligand, to maintain germline stem cell pools. Using fixed germlines, it was recently shown that the transcription of a Notch target gene decreased relatively early-on during adulthood. Here, we used the genetically encoded Notch Sensor Able to detect Lateral Signaling Activity (SALSA) to examine the pattern of GLP-1/Notch activity across the aging distal gonad in vivo. Interestingly, we find that the robust and progressively decreasing distal-proximal Notch activation gradient that is observed in young adults gets entirely lost during aging.

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van Vuuren, R. J. J., Narbonne, P., Martel, P.-O.. 2025-10-23. Loss of the distal-proximal GLP-1/Notch activation gradient in the aging C. elegans germline. https://doi.org/10.1101/2025.10.22.683991

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