Biochemistry I - Receptor biochemistry

We congratulate Tobias Strasdeit on achieving his doctorate degree.

We congratulate Peer Henning Höcker on achieving his doctorate degree.

The delta receptor GluD2 is an unusual mem­ber of the ionotropic glutamate receptor (iGluR) family. Most iGluRs can be activated by the neurotransmitter glutamate, with some additionally requring glycine or D-serine as a co-agonist. The activation leads to opening of a channel that allows the influx of ions into the cell. GluD2 has a functional ion channel and can bind glycine or D-serine, yet the binding is weak and does not open the channel. In collaboration with the group of Jette Kastrup at the Department of Drug Design and Phar­ma­col­ogy at the University of Copenhagen, we have now investigated why D-serine binds so weakly to GluD2. We found that a small, so-called hinge region is responsible for the weak binding. This region is located in the domain of the receptor that binds D-serine and serves as a hinge for a closing movement trapping D-serine inside the protein. Replacing this hinge region with that of another iGluR, GluN1, that binds D-serine much more strongly, transfers the strong binding to GluD2.

Abstract. The complete article is openly accessible.

We congratulate Sandra Lemos on achieving her doctorate degree.

We congratulate Madeline Ferreira Beltrán on achieving her doctorate degree.

We congratulate Thi Hong Thanh Lu on achieving her doctorate degree.

We congratulate Kevin Gottschling on achieving his doctorate degree.

In collaboration with the Clinical Neuro­science Group of Han­ne­lo­re Eh­ren­reich at the Max Planck Institute for Experimental Medicine in Göttingen we revealed that autoimmune reactions against NMDA receptors in the brain are more complex than previously thought – the antibodies formed can be of different types and recognize different parts of the receptor. Moreover, it became clear that antibodies against NMDA receptors in the blood are in principle always capable of triggering a disease in the brain, yet often don't do that. This means that a blood test positive for NMDA receptor antibodies alone is no proof for a neurological disease. The study has been published in Molecular Psychiatry. Press Release. Abstract. The complete article is openly accessible.

We congratulate Jan Terhag on achieving his doctorate degree.

Katya Spirova from the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry in Moscow, an institute of the Russian Academy of Sciences, joins our department for four weeks (the entire month of May) to do two-electrode voltage clamp recordings of oocyte-expressed nicotinic acetylcholine receptors. This is within a collaboration between us and the lab of Victor Tsetlin.

On Friday, 11 December 2015, the 10th Graduation Ceremony of the Faculty of Chemistry and Biochemistry took place in the Veranstaltungszentrum of the Ruhr University. Here you can find a report (in German) about the ceremony, which was again organised by the Department of Biochemistry I.

In Frontiers in Cellular Neuroscience we report on a new regulatory mechanism that acts as a feedback loop to control the number of kainate receptors expressed in the plasma membrane of astrocytes. In astrocytes trafficking to and expression in the membrane of the kainate receptor GluK2 depends, among other factors, on the activity of the serum- and gluco­corti­coid-dependent kinase 1, SGK1. Here we show that SGK1 simultaneously phosphorylates N-myc downstream regulated genes, NDRGs. NDRG2 in particular, when phosphorylated at T330, acts as a feedback inhibitor of GluK2 trafficking, thus counteracting and limiting the stimulatory effect of SGK1. Abstract. The complete article is openly accessible.

We congratulate Simon Haering on achieving his doctorate degree and wish him all the best for his new job in the USA.

In collaboration with chemists in the group of Dirk Trauner at the LMU Munich, who specialize in photopharmacology and chemical neuroscience, we report in Nature Communications the properties of a photoactivatable, soluble NMDA receptor agonist. This agonist, azobenzene-triazole-glutamate (ATG), can be converted from its inactive form to a specific NMDA receptor agonist by light of 365 nm wavelength. Light of 460 nm allows to trigger the return to the inactive form and thus switch off the receptor. We could show that all four types of classical NMDA receptors can be activated, which makes ATG an NMDA receptor-specific agonist that is switchable on a time scale of milliseconds. Abstract. The complete article is openly accessible.

In collaboration with colleagues at the Ben Gurion University of the Negev in Beer-Sheva, Israel, we investigated the effect of high pressure on the eight splice variants of the NMDA receptor subunit GluN1 coexpressed with the GluN2A subunit. In the European Journal of Neuroscience we show that all eight GluN1 splice variants mediate high pressure-induced potentiation of NMDA receptor currents (see example figure for GluN1-1a) and are thus involved in the upregulation of receptor currents to a similar extent as has previously been shown for the GluN2 subunits. The resulting hyperexcitability of the excitatory neurotransmitter system is believed to be the cause of neurological symptoms suffered by divers repetitively exposed to pressures above 1.1 MPa, and is thus of clinical relevance. Abstract.

In Frontiers in Cellular Neu­ro­science we report about the editing of GluA2 mRNA during the development of nerve cells. Editing of this subunit is of great importance for the normal function of AMPA-type glutamate receptors in the adult brain. Using an in vitro cell system we showed that editing occurs rapidly and completely upon differentiation of stem cells. The enzyme responsible for that is already present in the cells before GluA2 mRNA is produced. Abstract. The complete article is openly accessible.

On Friday, 12 December 2014, the 9th Graduation Ceremony of the Faculty of Chemistry and Biochemistry took place in the Veranstaltungszentrum of the Ruhr University. Here you can find a report (in German) about the ceremony, which was again organised by the Department of Biochemistry I.

We congratulate Veronika Matschke on achieving her doctorate degree.

In Membranes we have published a review on the intracellular trafficking of kainate-type glutamate receptors. We describe how these receptors are assembled, transported to the membrane, and finally recycled, including the role of auxiliary proteins. Abstract

In Membranes we have published a review on the influence of auxiliary subunits on AMPA-type glutamate receptors. In particular, we focus on the role of auxiliary subunits in transporting AMPA receptors to the membrane and anchoring them at synapses. Abstract

We congratulate Karina Eckey on achieving her doctorate degree.

We congratulate Svenja Pachernegg on achieving her doctorate degree.

In Frontiers in Cellular Neuroscience we report that embryonic stem cells already contain the mRNA for a number of glutamate receptors. However, this mRNA is not yet translated into protein. Therefore, the stem cells do not have functional glutamate receptors. Abstract. The complete article is openly accessible.

We congratulate Jürgen Trippe on achieving his doctorate degree.

In Science Signaling we report the characteristics of a receptor from the plant Ara­bidop­sis tha­li­ana that resembles the glutamate receptors in human and animal brains. Yet this plant receptor does not recognise glutamate but a number of other amino acids. Press Release. Abstract.

We congratulate Eva Wrobel on achieving her doctorate degree.

The CD to the lecture Biochemistry III, winter term 2012/2013 is now available. The CD contains all slides shown during the lecture. Copies of the CD can be bought in the departmental office (NC 6/171) or borrowed at the Fachschaft Chemistry and Biochemistry.

A postdoc position will be available at the Department of Biochemistry I - Receptor Biochemistry from 01 October 2012. Further information regarding the project and job requirements as well as contact information can be found in the official announcement (in German).

Prof. Guiscard Seebohm has been appointed W3 professor for Myocellular Electrophysiology at the University Hospital of Münster. He will take up his new position today. We congratulate him on this appointment and thank him for the excellent collaboration during the four years he spent in our department. We wish him and his entire group a speedy start in Münster and much success in his new job.

The CD to the lecture Biochemistry IV, summer term 2012 is now available. The CD contains all slides shown during the lecture. Copies of the CD can be bought in the departmental office (NC 6/171) or borrowed at the Fachschaft Chemistry and Biochemistry.

In PLoS One we report in collaboration with Prof. Onur Güntürkün’s group at the Faculty of Psychology that training the working memory increases the mRNA expression of certain, so-called D1-like dopamine receptors in the brain of pigeons. Depending on the particular tasks during the training, different receptor subunits are expressed more strongly. The training does not influence another kind of dopamine receptors, the D2 type. Abstract. The complete article is openly accessible.

We congratulate Katja Steinke on achieving her doctorate degree.

The CD to the lecture Biochemistry III, winter term 2011/2012 is now available. The CD contains all slides shown during the lecture. Copies of the CD can be bought in the departmental office (NC 6/171) or borrowed at the Fachschaft Chemistry and Biochemistry.

In Trends in Neurosciences we have published a review on the very diverse functional properties of the two NMDA receptor-modulating subunits GluN3A and GluN3B. In particular, we focus on their recently discovered non-canonical functions. Abstract

We congratulate Angela Orth on achieving her doctorate degree.

In The FASEB Journal we report how stress can trigger paralysis and arrhythmia in certain familial muscular disorders, and how these might be treated better in the future. More information can be found in a press release (in German only) and in the abstract (in English).

In Development we report in collaboration with Prof. Petra Wahle’s group at the Faculty of Biology and Biotechnology that certain glutamate receptors determine the architecture of nerve cells during brain development. Individual receptor variants enhance growth and branching of the nerve processes (dendrites) the cells communicate with. The growth-promoting property of the receptors is dependent on how much calcium they allow to flow into the cells. Press Release Abstract

The Faculty of Chemistry and Biochemistry of the Ruhr University Bochum is seeking to recruit a professor (W3, Department Chair) for Molecular Biochemistry. The position is to be filled by 1 October 2012. Applications will be accepted until Friday, 16 September 2011. A detailed job description and contact information can be found in the official job announcement.

We welcome Sandra Lemos, our latest team member, who will carry out her PhD within the EU-funded Marie Curie Initial Training Network “TRANSPOL”.

In Cellular Physiology and Biochemistry we report that ionotropic GluR subunit mRNA expression can be utilized to discriminate between neural stem cells (NSCs) and neuroepithelial precursor cells (NEPs) before and after the induction of neuronal differentiation. Abstract

In Frontiers in Molecular Neuroscience we report on the function of the transmembrane domain C of ionotropic glutamate receptors and show that this domain is involved in receptor gating. Abstract

A PhD position within a Marie Curie Initial Training Network of the European Union will be available at the Department of Biochemistry I - Receptor Biochemistry from 01 February or 01 March 2011. Further information regarding the project and job requirements as well as contact information can be found in the official announcement.

We say goodbye to our longtime employees Charlotte, Nora und Daniel, and wish them all the best!

In Science Signaling we summarize the latest findings regarding transsynaptic protein-protein interactions. The new, recently described mechanism involves the orphan glutamate receptor delta2 in the postsynaptic membrane, neurexin in the presynaptic membrane and precerebellin as the synaptic "glue" that connects the two proteins. Abstract

We congratulate Charlotte Sager on achieving her doctorate degree.

The CD to the lecture Biochemistry IV, summer term 2010 is now available. The CD contains all slides of Prof. Hollmann’s part of the lecture and additionally all slides of the Ringvorlesung 2010. Copies of the CD can be bought in the departmental office (NC 6/171) or borrowed at the Fachschaft Chemistry and Biochemistry.

In the Journal of Neurochemistry we report how kainate receptors are assembled from their subunits within the cell and how they are transported to the cell membrane. Abstract