TY  - JOUR
AU  - Spitz, Charlotte
AU  - Schlosser, Christine
AU  - Guschtschin-Schmidt, Nadja
AU  - Stelzer, Walter
AU  - Menig, Simon
AU  - Götz, Alexander
AU  - Haug-Kröper, Martina
AU  - Scharnagl, Christina
AU  - Langosch, Dieter
AU  - Muhle-Goll, Claudia
AU  - Fluhrer, Regina
TI  - Non-canonical Shedding of TNFα by SPPL2a Is Determined by the Conformational Flexibility of Its Transmembrane Helix.
JO  - iScience
VL  - 23
IS  - 12
SN  - 2589-0042
CY  - St. Louis
PB  - Elsevier
M1  - DZNE-2021-00090
SP  - 101775
PY  - 2020
AB  - Ectodomain (EC) shedding defines the proteolytic removal of a membrane protein EC and acts as an important molecular switch in signaling and other cellular processes. Using tumor necrosis factor (TNF)α as a model substrate, we identify a non-canonical shedding activity of SPPL2a, an intramembrane cleaving aspartyl protease of the GxGD type. Proline insertions in the TNFα transmembrane (TM) helix strongly increased SPPL2a non-canonical shedding, while leucine mutations decreased this cleavage. Using biophysical and structural analysis, as well as molecular dynamic simulations, we identified a flexible region in the center of the TNFα wildtype TM domain, which plays an important role in the processing of TNFα by SPPL2a. This study combines molecular biology, biochemistry, and biophysics to provide insights into the dynamic architecture of a substrate's TM helix and its impact on non-canonical shedding. Thus, these data will provide the basis to identify further physiological substrates of non-canonical shedding in the future.
KW  - Biochemistry (Other)
KW  - Biophysics (Other)
KW  - Structural Biology (Other)
LB  - PUB:(DE-HGF)16
C6  - pmid:33294784
C2  - pmc:PMC7689174
DO  - DOI:10.1016/j.isci.2020.101775
UR  - https://pub.dzne.de/record/154229
ER  -