Expression and distribution of AcNMCP1 in nuclei isolated from different root cell types. (A) Localization of the onion root zones used in this analysis and their corresponding DNA content determined by flow cytometry. (B) AcNMCP1 levels detected by immunoblotting with the anti-AcNMCP1 antibody. AcNMCP1 expression was abundant in the proliferating (m) and quiescent (q) meristems, although it decreased significantly in non-meristematic cells (e = elongation zone; d = differentiated zone). H1 histones stained with Coomasie blue were used as loading controls. (C) Peripheral (qP, mP, dP) and central (qC, mC, dC) confocal sections showing the distribution of AcNMCP1 in the periphery and nuclear interior of quiescent (q) and proliferating (m) meristems and in differentiated cells (d). Arrows in qC point to the nucleoplasmic aggregates of the protein in quiescent meristems and arrows in dP to the gaps in the peripheral distribution of the protein in differentiated cells. qP’, qC’, mP’, mC’, dP’, and dC’ show overlays of AcNMCP1 and DAPI staining.