Proteinaceous Deposits in Primary Vascular Parenchyma Cells in Pinus radiata Needle Traces

抄録

The cytoplasm of the primary vascular parenchyma cells of Pinus radiata short shoots contains proteinaceous deposits which appear granular in composition and are not membrane limited. ER-derived sacs containing proteinaceous material and showing breaks in their limiting membrane are often found in proximity to proteinaceous deposits. Stages suggestive of the transformation of rough ER into sacs are identifiable. It is suggested that ER-derived sacs migrate to a site in the cytoplasm where they release their contents following the rupture of their limiting membrane.