Abstract
We previously reported that deletion of an Arabidopsis ATG6, a component of phosphatidylinositol 3-kinase (PI3K) complex, causes male gametophytic phenotypes. We have recently found that each component of PI3K complex, such as VPS34 and VPS15, is also essential for pollen germination, which supported our previous findings. To reveal a role of ATG6-PI3K complex in pollen germination, we examined function and localization of ATG6. Expression of Arabidopsis ATG6 allowed yeast atg6/vps30 mutant cells to accumulate autophagic bodies and to transport CPY protein into vacuoles. This suggested that Arabidopsis ATG6 has dual functions in autophagy and in vacuolar protein sorting. In Arabidopsis suspension cells, GFP-ATG6 and GFP-VPS34 resides on the punctate structure, which involves ATG8, a marker protein of pre-autophagosomal structure. PI3K-complex is likely to play a role in autophagosome formation in plant cells.
