title: Polysialylation takes place in granulosa cells during apoptotic processes of atretic tertiary follicles.
abstract: In the neuronal system, polysialic acid (polySia) is known to be involved in several cellular processes such as the modulation of cell-cell interactions. This highly negatively-charged sugar moiety is mainly present as a post-translational modification of the neural cell adhesion molecule (NCAM). More than 20 years ago, differently glycosylated forms of NCAM were detected in the ovaries. However, the exact isoform of NCAM, as well as its biological function, remained unknown. Our analysis revealed that granulosa cells of feline tertiary follicles express the polysialylated form of NCAM-140. Unexpectedly, polySia was only expressed in the granulosa layers of atretic follicles and not of healthy follicles. By contrast, only the un-polysialylated form of NCAM was present on the membrane of granulosa cells of healthy follicles. To study a possible cellular function of polySia in feline follicles, a primary granulosa cell culture model was used. Interestingly, loss of polySia leads to a significant inhibition of apoptosis, demonstrating that polySia is involved during atretic processes in granulosa cells. Thus, polySia might not only directly influence regeneration processes as shown, for example, in the neuronal system, but also apoptosis.
authors.affiliation: Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, Giessen, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Kaese
authors.affiliation: Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, Giessen, Germany.
authors.forename: Christina E
authors.initials: CE
authors.lastname: Galuska
authors.affiliation: Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, Giessen, Germany.|Institute of Anatomy and Cell Biology, Medical Faculty, Justus-Liebig-University, Giessen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Simon
authors.affiliation: Leibniz Institute for Zoo and Wildlife Research (IZW), Berlin, Germany.
authors.forename: Beate C
authors.initials: BC
authors.lastname: Braun
authors.affiliation: Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, Giessen, Germany.|Cardiovascular and Metabolic Disorders Program, Duke-National University of Singapore, Singapore.
authors.forename: Hector A
authors.initials: HA
authors.lastname: Cabrera-Fuentes
authors.affiliation: Institute of Anatomy and Cell Biology, Medical Faculty, Justus-Liebig-University, Giessen, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Middendorff
authors.affiliation: Clinic of Obstetrics, Gynecology and Andrology for Small and Large Animals, Justus-Liebig-University, Giessen, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Wehrend
authors.affiliation: Leibniz Institute for Zoo and Wildlife Research (IZW), Berlin, Germany.
authors.forename: Katarina
authors.initials: K
authors.lastname: Jewgenow
authors.affiliation: Institute of Biochemistry, Medical Faculty, Justus-Liebig-University, Giessen, Germany.
authors.forename: Sebastian P
authors.initials: SP
authors.lastname: Galuska
mesh_terms: D000818:Animals; D017209:Apoptosis; D002415:Cats; D002478:Cells, Cultured; D005260:Female; D005496:Follicular Atresia / Q000378:metabolism*; D006107:Granulosa Cells / Q000378:metabolism*; D006080:Ovarian Follicle / Q000166:cytology / Q000378:metabolism; D012794:Sialic Acids / Q000378:metabolism*
chemical_list: D012794:Sialic Acids; C021319:polysialic acid
keywords: NCAM; apoptosis; folliculogenesis; granulosa cells; polysialic acid