Cell-specific polymerization-driven biomolecular condensate formation fine-tunes root tissue morphogenesis

Gassmann, W.; Su, J.; Xu, X.; Cseke, L.; Whittier, S.; Zhou, R.; Zhang, Z.; Dietz, Z.; Singh, K.; Yang, B.; Chen, S.-Y.; Picking, W.; Zou, X.

doi:10.1101/2024.04.02.587845

bioRxiv · 10.1101/2024.04.02.587845

Cell-specific polymerization-driven biomolecular condensate formation fine-tunes root tissue morphogenesis

Gassmann, W.·Su, J.·Xu, X.·Cseke, L.·Whittier, S.·Zhou, R.·Zhang, Z.·Dietz, Z.·Singh, K.·Yang, B.·Chen, S.-Y.·Picking, W.·Zou, X.

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Abstract

Formation of biomolecular condensates can be driven by weak multivalent interactions and emergent polymerization. However, the mechanism of polymerization-mediated condensate formation is less studied. We found lateral root cap cell (LRC)-specific SUPPRESSOR OF RPS4-RLD1 (SRFR1) condensates fine-tune primary root development. Polymerization of the SRFR1 N-terminal domain is required for both LRC condensate formation and optimal root growth. Surprisingly, the first intrinsically disordered region (IDR1) of SRFR1 can be functionally substituted by a specific group of intrinsically disordered proteins known as dehydrins. This finding facilitated the identification of functional segments in the IDR1 of SRFR1, a generalizable strategy to decode unknown IDRs. With this functional information we further improved root growth by modifying the SRFR1 condensation module, providing a strategy to improve plant growth and resilience.

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Gassmann, W., Su, J., Xu, X., Cseke, L., Whittier, S., Zhou, R., Zhang, Z., Dietz, Z., Singh, K., Yang, B., Chen, S.-Y., Picking, W., Zou, X.. 2024-04-03. Cell-specific polymerization-driven biomolecular condensate formation fine-tunes root tissue morphogenesis. https://doi.org/10.1101/2024.04.02.587845

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