Immunofluorescent images of formaldehyde-fixed cell lines are shown. Three different organelle markers are displayed as different channels in the multicolor images - nucleus stained in blue, microtubules in red and ER in yellow. The various cell structures that are demonstrated are always shown in the green channel using an antibody found in the Human Protein Atlas. The antibody id is linked to the corresponding Cell Atlas protein page. By using the "toggle channels"-buttons, the different channels can be turned on and off. Most cell structures can be highlighted in the cell illustration by hovering over them with the exception of the aggresome. Cytoplasmic bodies are highlighted as cytosol; cytokinetic bridge, midbody, midbody ring and mitotic spindle are highlighted as microtubules, cell junctions are highlighted as plasma membrane and nucleus is highlighted as nucleoplasm.
An aggresome is a cytoplasmic structure that contains misfolded proteins. It usually occurs under cellular stress conditions or when the degradation machinery of the cell is overwhelmed. Aggresome formation is an important cellular function as it deposes misfolded proteins into one location, thereby limiting possible cytotoxic effects of the misfolded proteins. Aggresome formation is dependent on the cytoskeleton as it is accompanied by a redistribution of the intermediate filaments that forms a cage around the aggresome. It is also dependent on the microtubule network as misfolded proteins are deposed into the aggresome by transport along the microtubules.
Aggresomes form in the cytoplasm and are usually positioned close to the nucleus, where they appear as a solid blob. Aggresome formation is characterized by a disruption of the microtubule network (red channel) making it easy to identify them. The presence of aggresomes varies between in vitro cultivated cell lines, as some cell types are more prone to aggresome formation than others.