Research reveals how filament interactions affect cellular networks

Little things matter: for example, an amino acid can completely change the architecture of the cell. Researchers from the Universities of Göttingen and Warwick have studied the structure and mechanics of the main component of the cell cytoskeleton: a protein known as actin. Actin is found in all living cells, with a range of important functions, from muscle contraction to signaling and cell shape.

This protein comes in two varieties called “isoforms,” known as gamma-actin and beta-actin. The difference between the two proteins is tiny; only a few amino acids vary in a single part of the molecule. Yet this small change has a big impact on the cell. In nature, we normally only find mixtures of the two isoforms. In their study, the researchers separated the two isoforms and analyzed them individually. The results were published in the journal Natural communications.

The researchers studied the behavior of filament networks, focusing particularly on the unique properties of each isoform. They used specialized techniques allowing them to evaluate the mechanics and dynamics of research models of cytoskeletal networks, drawing on expertise in biophysics in Göttingen and bioengineering in Warwick.

The results indicate that gamma-actin prefers to form rigid networks near the top of the cell, while beta-actin preferentially forms parallel bundles with a distinct organizational pattern. This difference is likely due to gamma-actin’s stronger interaction with specific types of positively charged ions, making its networks more rigid than those formed by beta-actin.

“Our results are convincing because they open new avenues for understanding the complex dynamics of protein networks within cells,” explains Professor Andreas Janshoff, from the Institute of Physical Chemistry at the University of Göttingen.

The research advances scientists’ understanding of fundamental cellular processes by shedding light on the specific biological functions of actin, which will be particularly relevant to processes involving cellular mechanics such as cell growth, division and maturation. in tissues.

“The implications of these findings extend to the broader field of cell biology, offering insights that could impact many areas of research and applications, for example in developmental biology,” adds Janshoff.