Cells come in a variety of shapes, from the flat, scale-like cells that line the inside of your cheek to the long, cylindrical cells that make up your muscles. How cells acquire their shapes has been a mystery for scientists, but a new study published in the journal Nature has identified a key player in this process: a protein complex called the septin ring.

The septin ring is a complex of six proteins that forms a ring-shaped structure just beneath the cell membrane. Previous studies have shown that the septin ring is involved in a number of cellular processes, including cell division and cytokinesis, the process by which a cell divides into two new cells.

The new study shows that the septin ring also plays a role in cell shape determination. By manipulating the septin ring in human cells, the researchers were able to change the shape of the cells. For example, they could make the cells rounder or more elongated.

The researchers believe that the septin ring determines cell shape by regulating the tension of the cell membrane. The septin ring acts like a scaffold that helps to support the cell membrane and maintain its shape. When the septin ring is disrupted, the cell membrane becomes less tense and the cell can change shape.

The discovery of the septin ring's role in cell shape determination could have implications for understanding and treating a number of diseases. For example, defects in the septin ring could lead to cell shape changes that are associated with cancer and other diseases. By understanding how the septin ring works, scientists may be able to develop new therapies to treat these diseases.