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Title: Mechanism and function of root circumnutation

Early root growth is critical for plant establishment and survival. We have identified a molecular pathway required for helical root tip movement known as circumnutation. Here, we report a multiscale investigation of the regulation and function of this phenomenon. We identify key cell signaling events comprising interaction of the ethylene, cytokinin, and auxin hormone signaling pathways. We identify the geneOryza sativahistidine kinase-1 (HK1) as well as the auxin influx carrier geneOsAUX1as essential regulators of this process in rice. Robophysical modeling and growth challenge experiments indicate circumnutation is critical for seedling establishment in rocky soil, consistent with the long-standing hypothesis that root circumnutation facilitates growth past obstacles. Thus, the integration of robotics, physics, and biology has elucidated the functional importance of root circumnutation and uncovered the molecular mechanisms underlying its regulation.

 
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Award ID(s):
1915445 1806833
NSF-PAR ID:
10214350
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
8
ISSN:
0027-8424
Page Range / eLocation ID:
Article No. e2018940118
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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