Biology subjects

Raine, J.

Publications and source records attributed to Raine, J..

4 recordsLinked to original sources

bioRxiv2025

Role of chrna5 in multi-substance preference and phenotypes comorbid with the development of substance dependence

Addiction to nicotine and alcohol continues to be a leading cause of death and loss of productivity as measured in disability-adjusted life years. Polymorphisms in the nicotinic acetylcholine receptor subunit 5 (CHRNA5) have been identified as risk factors associated with nicotine dependence in human genetic studies and rodent models. Whether the chrna5 function is independently relevant to phenotypes associated with disorders comorbid with substance use, and if genetic factors influence subsequent outcomes when exposure to psychoactive substances happens at an early age, are questions of interest. We generated a stable mutant line in zebrafish using the CRISPR-Cas9 technique. We found that the chrna5 mutant fish exhibit an increased acute preference to both nicotine and alcohol in the Self-Administration Zebrafish Assay (SAZA). When subjected to multi-day exposures to either, chrna5 mutants exhibited greater behavioural change, but reduced transcriptomic changes compared to WT siblings, suggesting an impaired homeostatic regulation following drug exposure. Further, chrna5 mutants exhibited drug-independent changes in appetite and circadian rhythms, suggesting a genetic predisposition to disorders often comorbid with substance dependence. We expect these results to give new insights into the operation of genes whose normal function modulates vulnerability to multi-substance use and comorbid disorders.

neuroscience↗

bioRxiv2024

Spatial mRNA profiling using Rapid Amplified Multiplexed-FISH (RAM-FISH)

Spatial localization of multiple mRNAs in intact tissues provides vital insights into development and function, yet routine multiplexed imaging remains constrained by complex workflows, specialized equipment costs, or sample preparation requirements. Here, we present Rapid Amplified Multiplexed FISH (RAMFISH), an accessible, modular, benchtop workflow for targeted spatial mRNA profiling in intact tissues and whole-mount specimens. RAMFISH achieves reliable multiplexing of over 30 transcripts through iterative cycles of standard hybridization either manually or via open-source automation and imaging in shared confocal systems. To streamline analysis, we introduce an integrated, open-source pipeline automating signal normalization, rigid and non-rigid alignment, Laplacian of Gaussian spot calling, and 30-channel composite merging. We validate the platform by mapping multiple transcripts in developing Bicyclus anynana butterfly wings and intact 14 days-post-fertilization Danio rerio larvae, resolving both historically inferred domains and newly characterized gene expression. Overall, RAMFISH methodology offers an end-to-end, completely open-source ecosystem for robust, semi-quantitative, spatial mRNA mapping on a variety of sample types. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/627193v4_ufig1.gif" ALT="Figure 1"> View larger version (47K): org.highwire.dtl.DTLVardef@14dc9a3org.highwire.dtl.DTLVardef@1f11e3dorg.highwire.dtl.DTLVardef@f85483org.highwire.dtl.DTLVardef@1746701_HPS_FORMAT_FIGEXP M_FIG C_FIG

developmental biology↗

bioRxiv2024

chrna3 modulates biphasic response to alcohol

Alcohol use disorders (AUDs) are complex phenomena governed by genetics, neurophysiology, environment, and societal structures. New methods to understand the underlying neurogenetics are valuable for designing personalised interventional strategies. Here, we used a two-choice self-administration zebrafish assay (SAZA) to isolate the function of nicotinic acetylcholine receptor (nAChR) subunit alpha3 (chrna3) in alcohol response. Juvenile zebrafish, prior to sex differentiation, were examined in this study. They exhibited a biphasic response when self-administering alcohol that transitioned from attraction to aversion within minutes, suggesting they can regulate exposure to alcohol. This inverted U-shaped self-administration mirrored the effect alcohol has on shoaling behaviour. Exposure to low concentration of alcohol reduced anxiety-like behaviours, while sedative effects became prominent at higher concentrations resulting in reduced locomotion and uncoordinated swimming. In contrast, these responses are blunted in chrna3 mutants. They exhibited prolonged alcohol self-administration, and increased gregariousness. Transcriptomic analyses suggest that glutamatergic and GABAergic neurotransmission alongside cholinergic signalling is impacted in the mutant brains. Our results thus suggest that chrna3 dysfunction has a systemic change with an increase in alcohol tolerance being one effect. These findings also highlight the use of non-rodent alternatives to understand the neurogenetics of development of AUD.

neuroscience↗

bioRxiv2023

Evaluating the transmission risk of amyloid beta peptide via ingestion

BackgroundRecent reports suggest that amyloid beta (A{beta}) peptides can exhibit prion-like pathogenic properties. Transmission of A{beta} peptide and the development of associated pathologies after surgeries with contaminated instruments and intravenous or intracerebral inoculations have now been reported across fish, rodents, primates, and humans. This raises a worrying prospect of A{beta} peptides also having other characteristics typical of prions, such as evasion of the digestive process. We asked if such transmission of A{beta} aggregates via ingestion was possible. MethodsWe made use of a transgenic Drosophila melanogaster line expressing human A{beta} peptide prone to aggregation. Fly larvae were fed to adult zebrafish under two feeding schemes. The first was a short-term, high-intensity scheme over 48 hours to determine transmission and retention in the gut. The second, long-term scheme specifically examined retention and accumulation in the brain. The gut and brain tissues were examined by histology, western blotting, and mass spectrometric analyses. ResultsNone of the analyses could detect A{beta} aggregates in the guts of zebrafish following ingestion, despite being easily detectable in the feed. Additionally, there was no detectable accumulation of A{beta} in the brain tissue or development of associated pathologies after prolonged feeding. ConclusionsWhile human A{beta} aggregates do not appear to be readily transmissible by ingestion across species, two prospects remain open. First, this mode of transmission, if occurring, may stay below a detectable threshold and may take much longer to manifest. A second possibility is that the human A{beta} peptide may not be able to trigger self-propagation or aggregation in other species. Either possibility requires further investigation, taking into account the possibility of such transmission from agricultural species used in the food industry.

neuroscience↗