An Improved Immunolabeling Method for Microtubular Cytoskeleton in Poplar (Populus nigraL) Free Nuclear Endosperm

Abstract
We investigated immunocytochemical staining of microtubular cytoskeleton of free nuclear endosperm, a tissue which is particularly difficult to fix. This tissue requires fixation for 45 hr to preserve the integrity of the microtubular network after paraformaldehyde based fixation. Low glutaraldehyde concentration in the fixative and the ethanol dehydration retains β-tubulin antigenicity and the former improves preservation of tissue structure. An ethanol-free embedding method is recommended for immunocytochemical studies of ethanol sensitive target proteins.