Biology subjects

Schuster, K.

Publications and source records attributed to Schuster, K..

4 recordsLinked to original sources

bioRxiv2026

The genome of the coral model sea anemone Exaiptasia diaphana (Aiptasia) strain F003

We present a genome assembly of Aiptasia strain F003, a broadly used laboratory strain of the sea anemone and coral model organism Exaiptasia diaphana (Cnidaria; Anthozoa; Hexacorallia; Actiniaria; Aiptasiidae; Exaiptasia). The genome assembly spans 237.34 Mb across 12,480 contigs with a contig N50 of 76.47 kb (12,423 scaffolds with a scaffold N50 of 77.93 kb), including a single-contig mitochondrial genome with a length of 19.79 kb. The assembly is highly complete with a BUSCO completeness of 96.50% based on the metazoa dataset, including 94.80% single-copy, 1.70% duplicated, 1.70% fragmented, and 1.80% missing BUSCO genes. Genome annotation identified 29,589 protein-coding genes (including 2 pseudogenes) and a repeat content of 32.89%. The genome of the female Aiptasia strain F003 enhances the utility of a key cnidarian model organism by enabling comparisons among Aiptasia strains in studies of symbiosis, microbiomes, and thermal stress. It thereby strengthens the value of Aiptasia as a model for investigating the mechanisms underlying coral holobiont function, response, and resilience to environmental change.

genomics↗

bioRxiv2026

Pathogen priming reveals host immune training and microbiome conditioning in corals

UNSTRUCTURED ABSTRACTIn several species, vaccine-like approaches, where hosts are primed through controlled pathogen exposure, have proven effective in enhancing responses to subsequent infections. This principle remains unexplored in corals. Here, we demonstrate that chronic exposure to non-lethal concentrations of live or inactivated Vibrio coralliilyticus primes the coral holobiont to counter subsequent infections under heat stress. Non-primed corals experienced greater heat stress pathogen-driven bleaching and a significant decline in their photosynthetic efficiency compared to primed samples. These results were linked to microbiome conditioning and host gene expression modulation, including a layered, fine-tuned immune and cellular response to microbial invasion. This proof-of-concept challenges strictly innate immune responses in corals and positions immune priming and microbiome conditioning as integrated mechanisms of coral holobiont resilience. Together, these findings can contribute to redefine coral immunity concepts and lay the groundwork for developing new microbiome-based strategies to enhance coral health for reef conservation under climate change. LAY SUMMARYCoral reefs are increasingly threatened by rising seawater temperatures and disease. Unlike vertebrates, corals do not possess a classical adaptive immune system, so they have been thought to rely only on innate defenses. However, our study shows that corals may be more capable than previously believed. We demonstrate that exposing corals to non-lethal doses of a widespread bacterial pathogen can train them to better withstand subsequent infections under heat stress. Corals that were not pre-exposed suffered more pathogen caused bleaching and showed a stronger decline in physiological performance, while those that were primed were more resilient. This improved resistance appears to come from two coordinated processes. First, the corals associated bacterial community shifted in a way that seems to help protect the host. Second, the coral itself adjusted its gene expression, mounting a more effective and controlled response to infection. These findings suggest that corals may be able to remember past exposures and respond more effectively to future infections, even without a traditional adaptive immune system, providing a foundation for developing new strategies to support coral resilience.

microbiology↗

bioRxiv2020

Brain-wide mapping of water flow perception in zebrafish

Information about water flow, detected by lateral line organs, is critical to the behavior and survival of fish and amphibians. While certain specific aspects of water flow processing have been revealed through electrophysiology, we lack a comprehensive description of the neurons that respond to water flow and the network that they form. Here, we use brain-wide calcium imaging in combination with microfluidic stimulation to map out, at cellular resolution, all neurons involved in perceiving and processing water flow information in larval zebrafish. We find a diverse array of neurons responding to forward flow, reverse flow, or both. Early in this pathway, in the lateral line ganglia, these are almost exclusively neurons responding to the simple presence of forward or reverse flow, but later processing includes neurons responding specifically to flow onset, representing the accumulated volume of flow during a stimulus, or encoding the speed of the flow. The neurons reporting on these more nuanced details are located across numerous brain regions, including some not previously implicated in water flow processing. A graph theory-based analysis of the brain-wide water flow network shows that a majority of this processing is dedicated to forward flow detection, and this is reinforced by our finding that details like flow velocity and the total volume of accumulated flow are only encoded for the simulated forward direction. The results represent the first brain-wide description of processing for this important modality, and provide a departure point for more detailed studies of the flow of information through this network. Significance statementIn aquatic animals, the lateral line is important for detecting water flow stimuli, but the brain networks that interpret this information remain mysterious. Here, we have imaged the activity of individual neurons across the entire brains of larval zebrafish, revealing all response types and their brain locations as water flow processing occurs. We find some neurons that respond to the simple presence of water flow, and others that are attuned to the flows direction, speed, duration, or the accumulated volume of water that has passed during the stimulus. With this information, we modeled the underlying network, describing a system that is nuanced in its processing of water flow simulating forward motion but rudimentary in processing flow in the reverse direction.

neuroscience↗

bioRxiv2017

A multi-modal approach to decomposing standard neuropsychological test performance: Symbol Search

Neuropsychological test batteries provide normed assessments of cognitive performance across multiple functional domains. Although each test emphasizes a certain component of cognition, a poor score can reflect many possible processing deficits. Here we explore the use of simultaneous eye tracking and EEG to decompose test performance into interpretable, components of cognitive processing. We examine the specific case of Symbol Search, a \"processing speed\" subtest of the WISC, which involves searching for the presence of either of two target symbols among five search symbols. To characterize the signatures of effective performance of the test, we asked 26 healthy adults to perform a computerized version of it while recording continuous EEG and eye tracking. We first established basic gaze-shifting patterns in the task, such as more frequent and prolonged fixation of each target than each search symbol, and longer search symbol fixations and overall trial duration for target-absent trials. We then entered multiple such metrics into a least absolute shrinkage and selection operator (LASSO) analysis, which revealed that short trial completion times were mainly predicted by longer initial fixations on the targets and fewer subsequent confirmatory saccades directed back to the targets. Further, the tendency to make confirmatory saccades was associated with stronger gamma-amplitude modulation by mid-frontal theta-phase in the EEG during initial target symbol encoding. Taken together, these findings indicate that efficient Symbol Search performance depends more on effective memory encoding than on general \"processing speed\".

neuroscience↗