Transmission electron micrograph showing the extensive accumulation of darkly stained heterochromatin at the nuclear periphery typical of many differentiated cells. Heterochromatin is excluded from re...

Transmission electron micrographs of Opossum spermatogonia showing different regions within the nucleolus. One region is more lightly staining and fine textured, the other denser and more coarsely tex...

Transmission electron micrograph showing the highly compact nucleolus in the salamander hepatocyte. A finer textured central region is surrounded by a coarser region.

Transmission electron micrograph of a thin section of the nucleus of a HeLa cell expressing mutant ALADIN. Pore structure appears to be unaffected in the mutant. From a study of the role of the nuclea...

Transmission electron micrograph of glutaraldehyde fixed pancreatic acinar cell showing the characteristic features of nuclear chromatin with this preparative method. Darkly staining heterochromatin (...

Transmission electron micrographs of sections of tadpole oocyte show the potential for exchange between the nucleus and the cytoplasm at the nuclear envelope. Thin filaments that appear to traverse nu...

Transmission electron micrograph of a thin section of the nucleus of a normal HeLa cell showing detail of a cross section of a nuclear pore - from a study of the role of the nuclear porin ALADIN. Oth...

Transmission electron micrograph of a thin section of the nucleus of a normal HeLa cell showing a tangential view of the nuclear envelope with nuclear pores. From a study of the role of the nuclear po...

Nuclear pores are clearly seen in these transmission electron micrographs of cells after cryo-fixation, freeze-fracture and surface replication. Upper panel shows the outer surface of of the nuclear e...

Fluorescence images showing the distribution of GFP-ALADIN, a WD-repeat protein that is mutated in the human triple A syndrome (green), and Tpr, a nucleoporin that localizes to the nucleoplasmic filam...