Abstract
The central vacuole is the largest organelle in plant cells. It has various functions including accumulations of metabolites such as proteins, sugars, antibacterial substances and organic acids. Especially, vacuoles in seeds are referred to as protein storage vacuoles (PSVs), where a large amount of storage proteins are accumulated as nutrition for germination and subsequent growth. Vacuolar proteins are transported to vacuoles by vesicle trafficking after synthesis on endoplasmic reticulum. We have isolated several mutants with a defect of vacuolar protein sorting in maturing seeds of Arabidopsis thaliana. The gfs9 mutant is one of the vacuolar protein sorting mutants. We found that gfs9 mutant showed miniaturization of PSVs in seeds. We investigated vacuolar morphologies in the gfs9 cells during seed germination and embryo development. We also analyzed the effects of abnormal vacuolar morphology on the seed size.
