The 3D Ultrastructure of C. elegans Gut Granules

Archer, G.; Bartlowe, S.; Bayarbadrakh, B.; Bok, D.; Bushong, C.; Carroll, A.; Cole, M.; Dahl, E. J.; Denier, N.; Elewa, A.; El Harchi, H.; Fisher, D.; Grant, H.; Grinfeld, R.; Grijalva, A.; Hale, A.; Hendricks, C.; Iskandar, M.; Kagan, S.; Mistry, N.; Keuneke, H.; Lammers, L.; Lyons, A.; Maclin, Q.; Moore, T.; Munro, C.; Nickerson, G.; Papalia, B.; Peacock, K.; Ritzman, L.; Ross, A.; Samineni, R.; Scales, M.; Schotz, L.; Sikkema, W.; Slabaugh, T.; Sorenson, A.; Swisher, R.; Sutherland, S.; Valdes, D.; Ward, F.; Wojdyla, P.

doi:10.64898/2026.03.04.709038

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bioRxiv · 10.64898/2026.03.04.709038

The 3D Ultrastructure of C. elegans Gut Granules

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Abstract

We identify an endoderm-restricted organelle in published volume electron microscopy datasets of C. elegans embryos. The organelle consists of a tubular ring surrounding a membrane-bound compartment harboring a prominent dense particle and exhibits a basal polarity and size concordant with canonical gut granules. This finding offers ultrastructural detail to recent evidence that gut granules are bi-lobed organelles with two distinct compartments.

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Archer, G., Bartlowe, S., Bayarbadrakh, B., Bok, D., Bushong, C., Carroll, A., Cole, M., Dahl, E. J., Denier, N., Elewa, A., El Harchi, H., Fisher, D., Grant, H., Grinfeld, R., Grijalva, A., Hale, A., Hendricks, C., Iskandar, M., Kagan, S., Mistry, N., Keuneke, H., Lammers, L., Lyons, A., Maclin, Q., Moore, T., Munro, C., Nickerson, G., Papalia, B., Peacock, K., Ritzman, L., Ross, A., Samineni, R., Scales, M., Schotz, L., Sikkema, W., Slabaugh, T., Sorenson, A., Swisher, R., Sutherland, S., Valdes, D., Ward, F., Wojdyla, P.. 2026-03-04. The 3D Ultrastructure of C. elegans Gut Granules. https://doi.org/10.64898/2026.03.04.709038

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