Septin

Septins are a group of GTPase enzymes that are involved in various cellular processes, including cell division, cytokinesis, and cell cycle regulation. They are conserved in eukaryotes, indicating their essential role in the cell biology of organisms ranging from yeast to humans. Septins form hetero-oligomeric complexes that can assemble into filaments, rings, and gauzes, which are critical for their function in cell division and other processes.

Structure and Function

Septins are characterized by their GTP-binding domain, which is essential for their activity. They can bind and hydrolyze GTP, a process that is crucial for their assembly and disassembly dynamics. Septins typically form complexes of 6 to 8 different septin proteins, which then polymerize into higher-order structures. These structures can act as scaffolds or barriers at the cell membrane, influencing the localization and activity of other proteins.

In cell division, septins are particularly important during cytokinesis, the process that physically separates the daughter cells. They localize to the cleavage furrow, where they help to organize the cytoskeleton and membrane components necessary for cell division. Septins also play a role in membrane compartmentalization, aiding in the formation of specialized cell membrane domains.

Role in Disease

Alterations in septin function or expression have been linked to various diseases, including neurodegenerative diseases, cancer, and infectious diseases. For example, mutations in septin genes have been associated with the development of certain types of cancer, as they may contribute to uncontrolled cell division. In neurodegenerative diseases, abnormal septin dynamics can affect neuronal cell shape and function, leading to cell death.

Research and Therapeutic Potential

Given their role in critical cellular processes and disease, septins have become a focus of research for the development of therapeutic interventions. Small molecules that modulate septin assembly and disassembly are being explored as potential drugs for cancer and other diseases. Understanding the precise mechanisms by which septins contribute to disease may lead to novel therapeutic strategies targeting these proteins.

See Also

• GTPase
• Cell division
• Cytokinesis
• Cell cycle
• Neurodegenerative diseases
• Cancer