Skip to Content
Merck

Mechanism and function of root circumnutation.

Proceedings of the National Academy of Sciences of the United States of America (2021-02-21)
Isaiah Taylor, Kevin Lehner, Erin McCaskey, Niba Nirmal, Yasemin Ozkan-Aydin, Mason Murray-Cooper, Rashmi Jain, Elliot W Hawkes, Pamela C Ronald, Daniel I Goldman, Philip N Benfey
ABSTRACT

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 gene Oryza sativa histidine kinase-1 (HK1) as well as the auxin influx carrier gene OsAUX1 as 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.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
2-Naphthaleneacetic acid, 99%
Sigma-Aldrich
trans-Zeatin hydrochloride, suitable for plant cell culture, ≥97%
Sigma-Aldrich
1-Naphthaleneacetic acid, suitable for plant cell culture, BioReagent, ≥95%, crystalline
Supelco
Naptalam, PESTANAL®, analytical standard
Sigma-Aldrich
trans-Zeatin, BioReagent, suitable for plant cell culture, ≥97%