Biology subjects

Currie, S.

Publications and source records attributed to Currie, S..

4 recordsLinked to original sources

bioRxiv2024

A Novel 3D Imaging Approach for Quantification of GLUT4 Levels across the Intact Myocardium

Cellular heterogeneity is a well-accepted feature of tissues, and both transcriptional and metabolic diversity have been revealed by numerous approaches, including optical imaging. However, the high magnification objective lenses needed for high-resolution imaging provides information from only small layers of tissue, which can result in poor cell statistics. There is therefore an unmet need for an imaging modality that can provide detailed molecular and cellular insight within intact tissue samples in 3D. Using GFP-tagged GLUT4 as proof of concept, we present here a novel optical mesoscopy approach that allows precise measurement of the spatial location of GLUT4 within specific anatomical structures across the myocardium in ultrathick sections (5 mm x 5 mm x 3 mm) of intact mouse heart. We reveal distinct GLUT4 distribution patterns across cardiac walls and highlight specific changes in GLUT4 expression levels in response to high fat diet-feeding, and we identify gender-dependent differences in expression patterns. This method is applicable to any target that can be labelled for light microscopy, and to other complex tissues when organ structure needs to be considered simultaneously with cellular detail. SUMMARY STATEMENTHere we present a novel 3D optical mesoscopy approach that allows the study of both GLUT4 protein expression levels and structural distribution within ultrathick sections of intact murine hearts, in response to high fat diet-feeding.

cell biology↗

bioRxiv2023

A cranial implant for stabilizing whole-cell patch-clamp recordings in behaving rodents

BackgroundIn vivo patch-clamp recording techniques provide access to the sub- and suprathreshold membrane potential dynamics of individual neurons during behavior. However, maintaining recording stability throughout behavior is a significant challenge, and while methods for head restraint are commonly used to enhance stability, behaviorally related brain movement relative to the skull can severely impact the success rate and duration of whole-cell patch-clamp recordings. New methodWe developed a low-cost, biocompatible, and 3D-printable cranial implant capable of locally stabilizing brain movement, while permitting equivalent access to the brain when compared to a conventional craniotomy. ResultsExperiments in head-restrained behaving mice demonstrate that the cranial implant can reliably reduce the amplitude and speed of brain displacements, significantly improving the success rate of recordings across repeated bouts of motor behavior. Comparison with existing methodsOur solution offers an improvement on currently available strategies for brain stabilization. Due to its small size, the implant can be retrofitted to most in vivo electrophysiology recording setups, providing a low cost, easily implementable solution for increasing intracellular recording stability in vivo. ConclusionsBy facilitating stable whole-cell patch-clamp recordings in vivo, biocompatible 3D printed implants should accelerate the investigation of single neuron computations underlying behavior.

neuroscience↗

bioRxiv2023

Social experience influences thermal sensitivity: lessons from an amphibious mangrove fish

Understanding factors affecting ectothermic fishes capacity to cope with warming temperature is critical given predicted climate change scenarios. We know that a fishs social environment introduces plasticity in how it responds to high temperature. However, the magnitude of this plasticity and the mechanisms underlying socially-modulated thermal responses are unknown. Using the amphibious, selfing hermaphroditic mangrove rivulus fish (Kryptolebias marmoratus) as a model, we tested three hypotheses: 1) social stimulation affects physiological and behavioural thermal responses of isogenic lineages of fish, 2) social experience and acute social stimulation result in distinct physiological and behavioural responses, and 3) a desensitization of thermal receptors is responsible for socially modulated thermal responses. To test the first two hypotheses, we measured the temperature at which fish emerged (i.e., pejus temperature) with acute warming with socially naive, isolated fish and socially experienced fish. Our results did not support our first hypothesis as fish socially-stimulated by mirrors during warming (i.e., acute social stimulation) emerged at similar temperatures as isolated fish. However, in support of our second hypothesis, prior social experience resulted in fish emerging at a higher temperature than socially naive fish suggesting an increase in pejus temperature with social experience. We measured whole-body cortisol concentrations of socially naive and socially experienced fish and determined that socially experienced fish had significantly higher cortisol concentrations than socially naive fish. To test our third hypothesis, we exposed socially experienced and naive fish to capsaicin, an agonist of TRPV1 thermal receptors. Socially experienced fish emerged at significantly higher capsaicin concentrations than socially naive fish suggesting a desensitization of their TRPV1 thermal receptors. Collectively, our data indicate that past and present social experiences impact the behavioural response of fish to high temperature. We also provide novel data suggesting that social experience affects the capacity of fish to perceive warm temperature.

physiology↗

bioRxiv2017

Development of High-Throughput Screening Assays for Inhibitors of ETS Transcription Factors

ETS transcription factors from the ERG and ETV1/4/5 subfamilies are overexpressed in the majority of prostate cancer patients and contribute to disease progression. Here, we develop two in vitro assays for the interaction of ETS transcription factors with DNA that are amenable for high throughput screening. Using ETS1 as a model, these assays were applied to screen 110 compounds derived from a high-throughput virtual screen. We find that the use of lower affinity DNA-binding sequences, similar to those which ERG and ETV1 bind to in prostate cells, allowed for higher inhibition from many of these test compounds. Further pilot experiments demonstrated that the in vitro assays are robust for ERG, ETV1, and ETV5, three of the ETS transcription factors that are overexpressed in prostate cancer.

biochemistry↗