MoLife Research Seminar
Prof. Dr. rer. nat. Regina Fluhrer
Biomedizinisches Centrum (BMC), München, Germany / Biochemistry and Molecular Biology, University of Augsburg
Title of the talk:
SPPL - Proteases: Important Players in Transport and Glycosylation
Intramembrane cleaving GxGD-type aspartylproteases process their membrane bound substrates within the hydrophobic core of cellular membranes and are involved in a number of pivotal physiological and pathological processes like the development of Alzheimer’s Disease or viral infections. One family of GxGD-type aspartylproteases, the Signal Peptide Peptidase and Signal Peptide Peptidase-like (SPP/SPPL) protease family, specifically cleaves substrates with a type II (Nin) membrane orientation. Recently, we linked SPPL3 to the regulation of cellular N-glycosylation (Voss M et al, EMBO J. 2014 Dec 17;33(24):2890-905). Thus, regulating the SPPL3-expression is a potent switch to adapt the cellular glycan-pattern in response to environmental changes, for instance lack of nutrients or growth factors. Changes in glycan patterns play an important role in cancer metastasis. Our present studies provide evidence that cellular glucose levels play a crucial role in regulation of SPPL3 expression and SPPL3 knock out mice lack subcutaneous adipose tissue.
Another member of the SPP/SPPL-family, SPPL2c, is capable of cleaving SNARE-proteins and strongly impacts on cargo transport through the secretory pathway, also affecting glycoprotein maturation. This function is of critical importance in acrosome formation during sperm maturation. Spermatids of SPPL2c knock mice are characterized by altered glycan patterns and impaired acrosome formation (Papadopoulou AA et al, EMBO Rep. 2019 Mar;20(3). Epub 2019 Feb 7 and Niemeyer J, et al, EMBO Rep. 2019 Mar;20(3). Epub 2019 Feb 7).
All are kindly welcome!
Further Information by: Prof. Dr. Klaudia Brix, Professor of Cell Biology, Email: k.brix [at] jacobs-university.de, Link to Homepage: http://www.jacobs-university.de/ses/kbrix