Systematic morphological and morphometric analysis of identified olfactory receptor neurons in Drosophila melanogaster

The biophysical properties of sensory neurons are influenced by their morphometric and morphological features, whose precise measurements require high-quality volume electron microscopy (EM). However, systematic surveys nanoscale characteristics for identified scarce. Here, we characterize the morphology Drosophila olfactory receptor (ORNs) across majority genetically hairs. By analyzing serial block-face images cryofixed antennal tissues, compile an extensive data set based on 122 reconstructed 3D models 33 40 ORN types. Additionally, observe multiple novel features—including extracellular vacuoles within sensillum lumen, intricate dendritic branching, mitochondria enrichment in select ORNs, types, empty sensilla containing no neurons—which raise new questions pertinent to cell biology neurobiology. Our survey is critical future investigations into how size shape influence responses, sensitivity, circuit function.