Biology subjects

Price, H.

Publications and source records attributed to Price, H..

3 recordsLinked to original sources

bioRxiv2023

Analysis of intracellular transport dynamics using quantitative phase imaging and FRET-based calcium sensors

Understanding cellular responses to mechanical environmental stimuli is an essential goal of cellular mechanotransduction studies and remains a target for microscopy technique development. While fluorescence microscopy has been advanced for this purpose - its molecular sensitivity, the ability of quantitative phase imaging to visualize subcellular structure has yet to be widely applied, perhaps due to its limited specificity. Here we seek to combine Quantitative Phase Imaging (QPI) with a molecularly sensitive Forster resonance energy transfer (FRET) construct for cell mechanotransduction studies. The multimodal imaging instrument is applied to examine cellular response to hypo-osmotic stimulus by observing the influx of calcium ions using a FRET based sensor coupled with mapping of the redistribution of intracellular mass using QPI. The combined imaging modality enables discrimination of cell response by localized region and reveals distinct behavior for each. The analysis shows cell flattening and oscillatory mass transport in response to the stimulus. With the broad array of FRET sensors under development, the combination with QPI offers new avenues for studying cell response to environmental stimuli.

biophysics↗

bioRxiv2021

Environmental and molecular modulation of motor individuality in larval zebrafish

Innate behavioral biases such as human handedness are a ubiquitous form of inter-individual variation that are not strictly hardwired into the genome and are influenced by diverse internal and external cues. Yet, genetic and environmental factors modulating behavioral variation remain poorly understood, especially in vertebrates. To identify genetic and environmental factors that influence behavioral variation, we take advantage of larval zebrafish light-search behavior. During light-search, individuals preferentially turn in leftward or rightward loops, in which directional bias is sustained and non-heritable, and maintained by a habenula-rostral PT circuit. Here we use a medium-throughput recording strategy and unbiased analysis to show that significant individual to individual variation exists in wildtype larval zebrafish turning preference. We classify stable left, right, and unbiased turning types, with most individuals exhibiting a directional preference. Raising larvae at elevated temperature selectively reduces the leftward turning type and impacts rostral PT neurons, specifically. Exposure to conspecifics, variable salinity, environmental enrichment, and physical disturbance does not significantly impact inter-individual turning bias. Pharmacological manipulation of Notch signaling and carrying a mutant allele of a known Notch pathway affecter gene, gsx2, disrupted turn bias individuality in a dose-dependent manner. These results establish that larval zebrafish is a powerful vertebrate model for inter-individual variation with sensitivity to specific environmental perturbations and gene dosage.

neuroscience↗

bioRxiv2021

Characterizing stored red blood cells using ultra-high throughput holographic cytometry

Holographic cytometry is introduced as an ultra-high throughput implementation of quantitative phase image based on off-axis interferometry of cells flowing through parallel microfluidic channels. Here, it is applied for characterizing morphological changes of red blood cells during storage under regular blood bank condition. The approach allows high quality phase imaging of a large number of cells greatly extending our ability to study cellular phenotypes using individual cell images. Holographic cytology measurements show multiple physical traits of the cells, including optical volume and area, which are observed to consistently change over the storage time. In addition, the large volume of cell imaging data can serve as training data for machine learning algorithms. For the study here, logistic regression is used to classify the cells according to the storage time points. The results of the classifiers demonstrate the potential of holographic cytometry as a diagnostic tool.

bioengineering↗