Johannes Niemeyer, Torben Mentrup, Ronny Heidasch, Stephan A Müller, Uddipta Biswas, Rieke Meyer, Alkmini A Papadopoulou, Verena Dederer, Martina Haug-Kröper, Vivian Adamski, Renate Lüllmann-Rauch, Martin Bergmann, Artur Mayerhofer, Paul Saftig, Gunther Wennemuth, Rolf Jessberger, Regina Fluhrer, Stefan F Lichtenthaler, Marius K Lemberg, Bernd Schröder
Signal peptide peptidase (SPP) and the four homologous SPP-like (SPPL) proteases constitute a family of intramembrane aspartyl proteases with selectivity for type II-oriented transmembrane segments. Here, we analyse the physiological function of the orphan protease SPPL2c, previously considered to represent a non-expressed pseudogene. We demonstrate proteolytic activity of SPPL2c towards selected tail-anchored proteins. Despite shared ER localisation, SPPL2c and SPP exhibit distinct, though partially overlapping substrate spectra and inhibitory profiles, and are organised in different high molecular weight complexes...
February 7, 2019: EMBO Reports