Septin localization and function during autophagy
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.
KeywordsAutophagy Septins PAS Autophagosome Atg9 trafficking Non-canonical rings
We would like to thank Prof. Yoshinori Ohsumi, Tokyo Institute of Technology, Tokyo, for generously sharing 2xmCherry-Atg8 plasmid, Prof. Subba Rao, IISc, Bangalore, India, for the Golgi marker plasmid RFP-Imh1p-GRIP-pGS396 and Prof. Kausik Chakraborty, IGIB, India, for sharing Septin-GFP strains. This work was supported by Wellcome Trust/DBT India Alliance Intermediate Fellowship (509159-Z-09-Z) and JNCASR intramural funds to RM.
GB and PS have performed the experiments. GB and RM wrote the manuscript.
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