Search bioRxiv⌕ Search

Biology subjects

Wong, K. K. Y.

Publications and source records attributed to Wong, K. K. Y..

4 recordsLinked to original sources

Chemosensory modulation of eye-body coordination in larval zebrafish

Coordinated eye-body movements are essential for adaptive behavior, yet little is known about how multisensory input, particularly chemosensory cues, shapes this coordination. Using our enhanced Fish-on-Chips optofluidic platform, we uncovered complex dynamics in how larval zebrafish coordinate saccadic eye movements with tail flips. Under baseline conditions, spontaneous tail flips dynamically align with saccades in frequency and direction for coordinated turns. Chemosensory valence further modulates this coordination: death-associated cues intensify both the strength and relative frequency of coupled saccade-tail flips during turns, whereas food-related cues promote forward gliding without altering saccade coupling. Concurrent brain-wide neuronal imaging reveals that the zebrafish pallium represents the mapping between aversive valence and enhanced saccade-tail coordination, with stronger coupling associated with higher pallium activation. These findings uncover the neural representations and behavioral strategies by which chemosensory inputs of different valences are associated with amplified eye-body coordination and adaptive locomotion in a developing vertebrate, offering insights into principles of sensory-motor integration.

neuroscience↗

Tomographic-encoded multiphoton (TEMP) microscopy

Axial scanning in multiphoton microscopy (MPM) is typically realized by mechanically shifting either the objective or the sample. However, the scan speed is usually hindered by the mechanical inertia of the bulky mass. Although the extended depth of field provided by the non-diffracting beam allows fast volumetric imaging, it abandons the axial resolution. Here, we demonstrate a novel and powerful tomographic technique using the Bessel droplet in MPM, termed Tomographic-Encoded MultiPhoton (TEMP) microscopy. We show that benefiting from the high-order nonlinear excitation in MPM, the side-lobes cancellation and smaller beam focus of the Bessel droplet realize better image quality. The TEMP microscopy allows fast axial scanning, less risks of photodamage and photobleaching, and high-resolution and high-contrast imaging. Furthermore, fewer raw images are required for the 3D image reconstruction. To demonstrate its usability and advantages for scattering tissues and biomedical applications, we showcase the TEMP microscopy with highly scattering fluorescence microspheres and mouse brain slice. More details can be visualized by the Bessel droplet compared with the conventional Gaussian and Bessel beam. More importantly, the TEMP technique is an easy-plug-in method for the current microscopy system. The TEMP microscopy is promising for fast volumetric multiphoton imaging, especially for highly scattering tissues.

bioengineering↗

A neural circuit basis for bilateral olfactory input-enhanced chemosensory avoidance navigation

Our understanding of how bilaterian animals utilize parallel input channels from paired sensory organs to optimize chemosensory behavior and the underlying neural circuit mechanisms are limited. Here we developed microfluidics-based behavioral and brainwide imaging platforms to study the neural integration of binasal inputs and chemosensory avoidance in larval zebrafish. We show that larval zebrafish efficiently escape from cadaverine-carrying streams by making more frequent swim bouts and larger undirected turns. Binasal inputs are strictly required for the nasal input-dependent component of klinokinesis, while each nasal input additively enhances angular orthokinesis. Throughout brain regions, including those along the olfactory processing pathways, a distributed neural representation with a wide spectrum of ipsilateral-contralateral nasal stimulus selectivity is maintained. Nonlinear sensory information gain with bilateral signal convergence is especially prominent in neurons weakly encoding unilateral cadaverine stimulus, and associated with stronger activation of sensorimotor neurons in the downstream brain regions. Collectively, these results provide insights into how the vertebrate model sums parallel input signals to guide chemosensory avoidance behavior.

neuroscience↗

VIA: Generalized and scalable trajectory inference in single-cell omics data

Inferring cellular trajectories using a variety of omic data is a critical task in single-cell data science. However, accurate prediction of cell fates, and thereby biologically meaningful discovery, is challenged by the sheer size of single-cell data, the diversity of omic data types, and the complexity of their topologies. We present VIA, a scalable trajectory inference algorithm that overcomes these limitations by using lazy-teleporting random walks to accurately reconstruct complex cellular trajectories beyond tree-like pathways (e.g. cyclic or disconnected structures). We show that VIA robustly and efficiently unravels the fine-grained sub-trajectories in a 1.3-million-cell transcriptomic mouse atlas without losing the global connectivity at such a high cell count. We further apply VIA to discovering elusive lineages and less populous cell fates missed by other methods across a variety of data types, including single-cell proteomic, epigenomic, multi-omics datasets, and a new in-house single-cell morphological dataset.

bioinformatics↗