Biology subjects

Beresford, R. J.

Publications and source records attributed to Beresford, R. J..

3 recordsLinked to original sources

bioRxiv2025

From Sensory Detection to Motor Action: The Comprehensive Drosophila Taste-Feeding Connectome

Gustatory systems drive critical survival behaviors such as feeding, foraging, and social interactions. However, gustation remains one of the least mapped sensory modalities at the connectome level. Here, we present the first complete wiring diagram of the male Drosophila adult gustatory system, comprehensively reconstructing gustatory receptor neurons (GRNs) from peripheral organs in a contiguous electron microscopy volume spanning brain, cervical connective, and ventral nerve cord. Integrating this with existing datasets, we generated a pan-CNS, cross-sex connectome that reveals GRN diversity through connectivity-based clustering, molecular identity mapping, and sexual dimorphism analysis. We mapped all feeding motor neurons and traced complete sensory-to-motor pathways to feeding, foraging, endocrine, and social behavior circuits. The emerging circuit architectures reveal distinct circuits for nutrient assessment, motor control, neuroendocrine regulation, and courtship. This work defines the gustatory systems organization at synaptic resolution and provides a framework for understanding how internal states modulate sensory-driven decisions across behavioral contexts.

neuroscience↗

bioRxiv2025

Connectomics Reveals a Feed-Forward Swallowing Circuit Driving Protein Appetite

Nutrient state shapes not only what animals eat, but how they eat it. We lack circuit-level mechanisms explaining how gustatory and internal state information regulates feeding at the motor control level. In Drosophila, protein deprivation prolongs protein-specific feeding bursts, yet the detailed motor mechanisms underlying this change remain unknown. Using EM connectomics, we identified a feed-forward pathway from proteinsensitive gustatory receptor neurons to swallowing motor neurons. At its core is the Sustain neuron, which coordinates multiple swallowing motor neurons to move food efficiently through the cibarium and pharynx. This nutrient-dependent facilitation of swallowing sustains long feeding bursts, directly linking internal state to the temporal structure of the feeding motor program. Our findings reveal how a dedicated sensorimotor circuit translates physiological need into precise motor control to drive nutrient-specific feeding appetite and highlights the power of combining EM connectomics with experimental circuit dissection.

neuroscience↗

bioRxiv2021

A Creb3-Like Transcription Factor Coordinates ER Function uponFood Intake to Regulate Lipid Metabolism

Ingestion of nutrients elicits essential physiological responses, including absorption, digestion, cessation of feeding and nutrient storage. The endoplasmic reticulum (ER) is central to this nutritional homeostasis, since it regulates intracellular organelle function, drives intercellular communication and promotes metabolite distribution. We identified the Drosophila Creb3L-family transcription factor, CrebA, as the key metabolic regulator of ER function, thereby affecting lipid metabolism and feeding behavior. In response to feeding, CrebA activity is rapidly and transiently activated. CrebA directly drives the expression of the ER protein sorting machinery. We demonstrate that CrebA levels regulate lipid metabolism through lipoprotein secretion into the hemolymph and suppress feeding behavior. Further, CrebA mouse homologs are also upregulated in the liver following feeding and drive the transcriptional activation of ER protein sorting machinery genes in mammals. Our results reveal an evolutionarily conserved transcription switch which is turned on in response to food ingestion and orchestrates a negative feedback loop that promotes satiety by regulating ER function and protein secretion.

cell biology↗