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bioRxiv · 10.1101/2024.04.08.588603

A prion-like protein regulates the 2-dimensional to 3-dimensional growth transition in the moss Physcomitrium patens

Weeks, Z.·Chaturvedi, G.·Day, E.·Kelly, S.·Moody, L. A.
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Abstract

The colonization of the land by plants coincided with the evolution of 3-dimensional (3D) growth; the acquisition of apical cells with the capacity to rotate the plane of cell division. The moss Physcomitrium patens has recently been developed as a model to dissect the genetic basis of 3D growth, an invariable and unifying feature of all land plants. The cytokinin-unresponsive Ppnog1-R mutant incorrectly orients division planes in developing buds and thus fails to make the transition to 3D growth. To reveal the genetic interactors of the PpNOG1 gene, which encodes a protein with a C-terminal UBA domain, we performed a screen and identified the suppressor of nog1a (snog1a) mutant. We have mapped the causative mutation to a gene that encodes a prion-like protein related to FLOE2/3 and demonstrated that the mutant phenotypes observed in both a nog1 disruptant mutant (nog1dis) and snog1a can be attributed to changes in cytokinin perception. We present a revised model for 3D growth and suggest that the 2D-to-3D growth transition is regulated, at least in part, by liquid-liquid phase separation (LLPS). SUMMARY STATEMENTThe transition to 3D growth is negatively regulated by a prion-like protein that both alters cytokinin signaling and has been implicated in liquid-liquid phase separation (LLPS).

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Weeks, Z., Chaturvedi, G., Day, E., Kelly, S., Moody, L. A.. 2024-04-10. A prion-like protein regulates the 2-dimensional to 3-dimensional growth transition in the moss Physcomitrium patens. https://doi.org/10.1101/2024.04.08.588603

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