Supramolecular interactions between functional metal complexes and proteins.

This perspective illustrates the principles and applications of molecular recognition directed binding of transition metal complexes to proteins. After a brief introduction into non-covalent interactions and the importance of complementarity, the focus of the first part is on biological systems that rely on non-covalent forces for metal complex binding, such as proteins involved in bacterial iron uptake and the oxygen-storage protein myoglobin. The second part of the perspective will illustrate how the replacement of native with non-native metal-centres can give rise to artificial metalloenzymes with novel catalytic properties.

Effect of heat shock on neuronal cultures: importance of protein synthesis and HSP72 induction for induced tolerance and survival.

In this study the effects of 30 min heat-shock, ranging from 42 degrees C to 46 degrees C, on survival, protein synthesis and HSP72 expression were investigated in primary rat neuronal cultures. Heat-shock of 44 degrees C resulted in a complete, but transient inhibition of protein synthesis which recovered within 24 h. 46 degrees C heat-shock resulted in an irreversible inhibition of protein synthesis and complete neuronal loss within 24 h.

Evidence of apoptosis in primary neuronal cultures after heat shock.

We investigated the effects of 30-min heat shock on survival, DNA degradation, and nuclear morphology of primary rat cortical and hippocampal neurones. In cell cultures which were grown for 8 days in vitro (DIV), only a small portion of neurones showed apoptotic morphology after heat shock of 45 degrees C and typical DNA laddering was not detectable, despite the fact that nearly 50% of the neurones died within 24 h. The majority of the neurones presumably died by necrosis, as indicated by random DNA degradation.

Effect of trophic factors on delayed neuronal death induced by in vitro ischemia in cultivated hippocampal and cortical neurons.

The effect of trophic factors on neuronal survival after 30 min oxygen and glucose deprivation (in vitro ischemia) was studied in primary hippocampal and cortical neuronal cultures of rat. In vitro ischemia was produced at 37 degrees C by placing cultures in glucose-free medium, the oxygen content of which was removed by gassing with pure argon. After in vitro ischemia neurons were allowed to recover either in serum-free minimal essential medium (MEM) or in MEM containing 5% native horse serum, 100 ng/ml basic fibroblast growth factor (bFGF) or 10 ng/ml transforming growth factor-beta 1 (TGF-beta 1), respectively.

Developmental changes of RNA editing of glutamate receptor subunits GluR5 and GluR6: in vivo versus in vitro.

In the present series of experiments we compared the up-regulation of GluR5 and GluR6 mRNA editing during the transition from the embryonic to the adult state with changes in the extent of editing during neuronal development in vitro. RNA was isolated from rats, from the cerebral cortex, hippocampus and cerebellum of embryonic brains (E19) and adult brains (2 months old), as well as from neurons prepared from the cortex, hippocampus and cerebellum of embryonic brains (E19) and held in tissue culture for 2, 8 or 16 days. Quantification of mRNA editing was achieved by using standards prepared from plasmids with cDNA inserts derived from the edited and unedited state of both GluR5 and GluR6 mRNA.