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Biology subjects

Hoyer, C.

Publications and source records attributed to Hoyer, C..

2 recordsLinked to original sources

CX3CR1 modulates migration of resident microglia towards brain injury

Microglia are innate immune cells of the central nervous system (CNS). They extend their processes towards and migrate towards injuries in vivo. However, whether the fractalkine receptor (CX3CR1) influences microglial migration remains unknown. Label-free proteomic profiling predicted changes in RHO-signaling activity that hint at dysregulated cytoskeleton signaling in Cx3cr1-deficient murine cortex tissue. To further investigate microglial migration, we carried out 4-hour interval two-photon in vivo imaging for 72 hours after a laser lesion in the cortex. Cx3cr1-deficient microglia showed enhanced migration towards the lesion. Additionally, length and velocity of microglial fine processes extending towards the lesion were increased in Cx3cr1-deficient microglia. Migration remained unchanged in Ccr2-deficient mice, indicating that monocyte-derived macrophages/microglia did not contribute to microglia accumulation around the lesion. These results demonstrate microglia migration towards CNS injury and suggest CX3CR1 as a modulator of this. Manipulating microglia migration via CX3CR1 therefore is a potential target for treatment of CNS-injury.

neuroscience↗

Optimization of insect odorant receptor trafficking and functional expression via transient transfection in HEK293 cells

Insect odorant receptors show a limited functional expression in various heterologous expression systems including insect and mammalian cells. This may be in part due to the absence of key components driving the release of these proteins from the endoplasmic reticulum and directing them to the plasma membrane. In order to mitigate this problem we took advantage of small export signals within the human HCN1 and Rhodopsin that have been shown to promote protein release from the endoplasmic reticulum and the trafficking of post-Golgi vesicles, respectively. Moreover, we designed a new vector based on a bidirectional expression cassette to drive the functional expression of the insect odorant receptor co-receptor (Orco) and an odor-binding odorant receptor, simultaneously. We show that this new method can be used to reliably express insect odorant receptors in HEK293 cells via transient transfection and that is highly suitable for downstream applications using automated and high-throughput imaging platforms.

zoology↗