Endocytosis (heterophagy) in plant cells: Involvement of ER and ER-derived vesicles

Abstract

The ultrastructure of rice roots water-cultured with hemoglobin was investigated by electron microscopy. In the cortex cells of these roots, plasmalemma invaginations were found to be surrounded by ER or ER-derived vesicles. After pinching off from the plasmalemma, invagination-derived vacuoles were surrounded completely by ER or ER-derived vesicles. These surrounding structures inflated and finally joined together to form a new vacuole. This suggests that endocytosis involving ER or ER-derived vesicles occurs in rice roots.