Biology subjects

Liberles, S.

Publications and source records attributed to Liberles, S..

3 recordsLinked to original sources

bioRxiv2026

Enteric sensory neurons for nutrient detection and gut motility

The enteric nervous system (ENS) orchestrates gastrointestinal reflexes and brain-gut communication via molecularly diverse neurons. Among these, intrinsic primary afferent neurons (IPANs) are essential for detecting luminal nutrients and irritants, yet their molecular identities, sensory properties, and functions remain poorly resolved. Here, we establish a segment-resolved single-cell atlas of the murine ENS, including a comprehensive characterization of the gastric ENS. This resource defines a refined taxonomy of enteric neurons and glia and enabled the development of a genetic toolkit for molecularly defined IPANs. Using chemogenetics and calcium imaging, we discovered that myenteric neurons detect a wide range of nutrients, irritants, and cytokines. Nutrient detection depends on a functional connection between chemosensory epithelial cells and enteric neurons mediated by 5-HT--HTR3 axis. Through optogenetic analysis, we demonstrated segment-specific regulation of gut motility by different IPANs. Our work establishes a genetic and physiological framework for enteric-specific sensory mechanisms.

neuroscience↗

bioRxiv2022

Enteroendocrine cell lineages that differentially control feeding and gut motility

Enteroendocrine cells are specialized sensory cells of the gut-brain axis that are sparsely distributed along the intestinal epithelium. The functions of enteroendocrine cells have classically been inferred by the gut hormones they release. However, individual enteroendocrine cells typically produce multiple, sometimes apparently opposing, gut hormones in combination, and some gut hormones are also produced elsewhere in the body. Here, we developed approaches involving intersectional genetics to enable selective access to enteroendocrine cells in vivo. We constructed Villin1-p2a-FlpO knock-in mice to restrict reporter expression to intestinal epithelium and through combined use of Cre and Flp alleles, effectively targeted major transcriptome-defined enteroendocrine cell lineages that produce serotonin, glucagon-like peptide 1, cholecystokinin, somatostatin, or glucose insulinotropic peptide. Chemogenetic activation of different enteroendocrine cell types variably impacted feeding behavior, nausea-associated behaviors (conditioned flavor avoidance), and gut motility. Defining the physiological roles of different enteroendocrine cell types provides an essential framework for understanding sensory biology of the intestine.

neuroscience↗

bioRxiv2020

Coordination of two enhancers drives expression of olfactory trace amine-associated receptors

Olfactory sensory neurons (OSNs) are functionally defined by their expression of a unique odorant receptor (OR). Mechanisms underlying singular OR expression are well studied, and involve a massive cross-chromosomal enhancer interaction network. Trace amine-associated receptors (TAARs) form a distinct family of olfactory receptors, and here we find that mechanisms regulating Taar gene choice display many unique features. The epigenetic signature of Taar genes in TAAR OSNs is different from that in OR OSNs. We further identify that two TAAR enhancers conserved across placental mammals are absolutely required for expression of the entire Taar gene repertoire. Deletion of either enhancer dramatically decreases the expression probabilities of different Taar genes, while deletion of both enhancers completely eliminates the TAAR OSN populations. In addition, both of the enhancers are sufficient to drive transgene expression in the partially overlapped TAAR OSNs. We also show that the TAAR enhancers operate in cis to regulate Taar gene expression. Our findings reveal a coordinated control of Taar gene choice in OSNs by two remote enhancers, and provide an excellent model to study molecular mechanisms underlying formation of an olfactory subsystem.

neuroscience↗