A magnetically enabled simulation of microgravity represses the auxin response during early seed germination on a microfluidic platform

Jing Du; Lin Zeng; Zitong Yu; Sihui Chen; Xi Chen; Yi Zhang; Hui Yang

doi:10.1038/s41378-021-00331-5

A magnetically enabled simulation of microgravity represses the auxin response during early seed germination on a microfluidic platform

Microsyst Nanoeng. 2022 Jan 14:8:11. doi: 10.1038/s41378-021-00331-5. eCollection 2022.

Authors

Jing Du¹, Lin Zeng¹, Zitong Yu¹, Sihui Chen¹, Xi Chen¹, Yi Zhang², Hui Yang¹

Affiliations

¹ Laboratory of Biomedical Microsystems and Nano Devices, Center for Bionic Sensing and Intelligence, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 China.
² Center for Medical AI, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055 China.

Abstract

For plants on Earth, the phytohormone auxin is essential for gravitropism-regulated seedling establishment and plant growth. However, little is known about auxin responses under microgravity conditions due to the lack of a tool that can provide an alteration of gravity. In this paper, a microfluidic negative magnetophoretic platform is developed to levitate Arabidopsis seeds in an equilibrium plane where the applied magnetic force compensates for gravitational acceleration. With the benefit of the microfluidic platform to simulate a microgravity environment on-chip, it is found that the auxin response is significantly repressed in levitated seeds. Simulated microgravity statistically interrupts auxin responses in embryos, even after chemical-mediated auxin alterations, illustrating that auxin is a critical factor that mediates the plant response to gravity alteration. Furthermore, pretreatment with an auxin transportation inhibitor (N-1-naphthylphthalamic acid) enables a decrease in the auxin response, which is no longer affected by simulated microgravity, demonstrating that polar auxin transportation plays a vital role in gravity-regulated auxin responses. The presented microfluidic platform provides simulated microgravity conditions in an easy-to-implement manner, helping to study and elucidate how plants correspond to diverse gravity conditions; in the future, this may be developed into a versatile tool for biological study on a variety of samples.

Keywords: Chemistry; Engineering.