Intercellular transport of macromolecules in nitella

Abstract

We injected three different fluorescein isothiocyanate (FITC)-labeled proteins, two different FITC-labeled dextrans and the photoprotein aequorin (the molecular weight of each being more than 20 kDa) into internodal cells of Nitella. All macromolecules with molecular weights equal to or less than 45 kDa moved from the injected cell to the neighboring nodal and internodal cells within 24 h after injection. The injected aequorin emitted light in the adjacent internodal cell upon a transient increase in the cytoplasmic concentration of Ca2+, an indication that the aequorin retained its function after transport between cells. © 1992 The Japanese Society of Plant Physiologists (JSPP).