INPROTEOLYS

Shahri Raasi

Research interest:

Dysfunctional ubiquitin signalling can cause abnormal conditions in the cell leading to different types of disorders, such as neuronal degeneration, defective immune response and various types of cancer. Ubiquitin-like (UBL) and ubiquitin-associated domains (UBA) are new players in ubiquitin signalling. They are small and highly degenerate protein motifs which occur in the context of larger proteins and act as intra- and/or intermolecular networking elements. The family of UBL-UBA proteins harbour both UBL and UBA domains. Via these domains they interact with various proteins and protein-complexes such as the multi-subunit enzyme complex 26S proteasome and ubiquitin conjugates. For instance, a common involvement of the UBL-UBA proteins Rad23 and Dsk2 with the ubiquitin-protein ligase Ufd2, the hexameric Cdc48 complex and its substrate-recruiting cofactors has been described in ERAD pathway. The reported protective effect of UBL-UBA proteins on ubiquitin chains and their association with ubiquitin ligase complexes support the idea that the UBL-UBA proteins might associate with the ubiquitin chains as they build on the substrate and protect them from deubiquitylating activities in the cell until substrates reach proteasome for degradation. Despite having common structural and functional similarities, UBL-UBA proteins reveal differential binding properties and substrate specificity which point to their functional diversity. Understanding the physiological meaning of the binding diversity of UBL-UBA proteins is the subject of my research activities in Konstanz.

E-mail		shahri.raasi@uni-konstanz.de

Phone		+49/7531/885172

Address		University of Konstanz, Department of Biology, Laboratory of Cellular Biochemistry, Box M642, 78457 Konstanz, Germany

Personal Web		-

Keywords		Ubiquitin, Proteasome, Ubiquitin receptors, Ubiquitin domain proteins, UBL-UBA proteins, ER-associated degradation, Protein-Protein interactions, Surface plasmon resonance