Aggresome

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.

Immunofluorescent staining

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.

Read more about the proteome of the cytosol.