Study shows how water transport in plants is regulated by cell membranes

In a recent study published in Nature Communications, scientists from the University of Illinois Urbana-Champaign explored how cell membranes can change the behavior of proteins embedded within them. Chemical and biomolecular engineering professor Diwakar Shukla led the research.

In the study, researchers focused on a specific protein called aquaporin, which acts as a microscopic water channel in cells. Aquaporins allow water molecules to pass through cell membranes while blocking other substances. Proper regulation of aquaporins is crucial for maintaining cell function, hydration and osmotic balance.

“Traditionally, we thought that a protein’s structure determined its function,” Shukla said. “However, proteins exist in a dynamic cellular environment, which can significantly affect their behavior. Until now, we didn’t fully understand how the lipid bilayer – a component of cell membranes – influences aquaporin function and dynamics.”

The team studied aquaporins because they are present in a wide variety of life forms, from yeast and bacteria to more complex organisms. These proteins play critical roles in human diseases and water regulation in plants, making their regulation important for drug development and conservation efforts. No matter where they are found or what type of membrane they are in, aquaporins must work properly, Shukla said.

The study revealed that the choice of membrane can significantly impact the thermodynamics, kinetics and overall behavior of proteins. By understanding how aquaporins behave in different cell membrane environments, researchers can gain insights into their roles in water conduction in different parts of the plants. Adjusting the local lipid conditions around aquaporins could help enhance their desired functions.

“We have a limited understanding of how plant membrane protein function is regulated due to the lack of extensive structural, sequence and functional datasets,” he said. “This study provides comprehensive insights into the functional regulation of a key plant protein.”

Under the oversight of Shukla, the research was carried out by Anh T.P. Nguyen and Austin T. Weigle while they were chemical and biomolecular engineering students. Nguyen is currently a graduate student at the Massachusetts Institute of Technology. Weigle is a SCINet/AI-CoE Postdoctoral Fellow at the U.S. Department of Agriculture and Agricultural Research Services.

The National Institute of General Medical Sciences of the National Institutes of Health supported this work.

Editor’s Note:

To reach Diwakar Shukla, email diwakar@illinois.edu

The paper “Functional regulation of aquaporin dynamics by lipid bilayer composition” is available online. DOI:10.1038/s41467-024-46027-y