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Updated: Jun 6, 2026

Analysis of Protein-protein Interactions and Co-localization Between Components of Gap, Tight, and Adherens Junctions in Murine Mammary Glands
Published on: May 30, 2017
Human axillary apocrine glands: proteins involved in the apocrine secretory mechanism
Mechthild Stoeckelhuber1, Christoph Schubert, Marco R Kesting
1Department of Oral and Maxillofacial Surgery, Technische Universität München, Munich, Germany. stoeckelhuber@mkg.med.tum.de
Abstract:
The apocrine secretory mechanism is a mode of secretion by which the apical part of the cell cytoplasm is pinched off, which leads to the formation of an aposome. The distinct mechanism of formation and decapitation of the aposome is not well investigated. Only few proteins are known that are involved in this secretory mechanism. We studied the human axillary apocrine gland and looked at proteins associated with cytokinesis, a process that is comparable to the pinching-off mechanism of apocrine glandular cells. By immunohistochemistry, we detected actin, myosin II, cytokeratin 7 and 19, α- and β-tubulin, anillin, cofilin, syntaxin 2, vamp8/endobrevin and septin 2. In highly active glandular cells, these proteins are located at the base of the apical protrusion when the aposome is in the process of being released or are concentrated in the cap of the apical protrusion. These findings demonstrate new insights on apocrine secretory mechanisms and point to similarities to the terminal step of cytokinesis, which is regulated by a SNARE-mediated membrane fusion event.
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