AUTHOR=Do Tien-Dung , Katsuyoshi Jimuro , Cai Haonai , Ohashi Toshiro 

TITLE=Mechanical Properties of Isolated Primary Cilia Measured by Micro-tensile Test and Atomic Force Microscopy

JOURNAL=Frontiers in Bioengineering and Biotechnology

VOLUME=Volume 9 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/bioengineering-and-biotechnology/articles/10.3389/fbioe.2021.753805

DOI=10.3389/fbioe.2021.753805

ISSN=2296-4185

ABSTRACT=Mechanotransduction is a well-known mechanism by which cells sense their surrounding mechanical environment, convert mechanical stimuli into biochemical signals, and eventually change their morphology and functions. Primary cilia are believed to be a mechanosensor existing on the surface of cell membrane and support cells to sense surrounding mechanical signals. Knowing mechanical properties of primary cilia would be essential to understand their responses such as sensitivity to mechanical stimuli. Previous studies have so far conducted flow experiments or optical trap techniques to measure the flexural rigidity EI (E: Young’s modulus, I: 2nd moment of inertia) of primary cilia, however, the flexural rigidity is not a material property of materials and depends on mathematical models used in the determination, leading to discrepancy between the studies. For better characterization of primary cilia mechanics, the Young’s modulus should be directly and precisely measured. In this study, the tensile Young’s modulus of isolated primary cilia was for the first time measured by using an in-house micro-tensile tester. The different strain rates of 0.01 s-1 - 0.3 s-1 were applied to isolated primary cilia, which showed a strain rate-dependent Young’s modulus in the range of 69.5 - 240.0 kPa on average. Atomic force microscopy was also performed to measure the local Young’s modulus of primary cilia, showing the Young’s modulus within the order of tens to hundreds of kPa. This study could directly provide the global and local Young’s moduli, which will come to benefits for better understanding of primary cilia mechanics.