Septin localization and function during autophagy.

Abstract

Autophagy is a vital conserved recycling process where eukaryotic cells remove unwanted proteins and organelles via lysosomal degradation and in turn, generate nutrients for the cells. The special feature of autophagy process is the formation of double-membrane vesicles called autophagosomes that engulf cellular cargo and deliver them to the vacuole or lysosomes for degradation. Inspite of more than 40 AuTophaGy (ATG) proteins and several organelles as known membrane source, autophagosome biogenesis is not entirely understood. We recently have discovered that septins contribute to autophagosome biogenesis. Septins are GTP-binding proteins, usually localized at the bud neck region and are involved in cytokinesis. Here, we show that during autophagy prevalent conditions, septins traffic between different cellular compartments such as Golgi, mitochondria, endosomes, plasma membrane, and vacuolar membranes.