20.500.12556/RUL-128327 Horsefly object-directed polarotaxis is mediated by a stochastically distributed ommatidial subtype in the ventral retina The ventral compound eye of many insects contains polarization-sensitive photoreceptors, but little is known about how they are integrated into visual functions. In female horseflies, polarized reflections from animal fur are a key stimulus for host detection. To understand how polarization vision is mediated by the ventral compound eye, we investigated the band-eyed brown horsefly Tabanus bromius using anatomical, physiological, and behavioral approaches. Serial electron microscopic sectioning of the retina and single-cell recordings were used to determine the spectral and polarization sensitivity (PS) of photoreceptors. We found 2 stochastically distributed subtypes of ommatidia, analogous to pale and yellow of other flies. Importantly, the pale analog contains an orthogonal analyzer receptor pair with high PS, formed by an ultraviolet (UV)-sensitive R7 and a UV- and blue-sensitive R8, while the UV-sensitive R7 and green-sensitive R8 in the yellow analog always have low PS. We tested horsefly polarotaxis in the field, using lures with controlled spectral and polarization composition. Polarized reflections without UV and blue components rendered the lures unattractive, while reflections without the green component increased their attractiveness. This is consistent with polarotaxis being guided by a differential signal from polarization analyzers in the pale analogs, and with an inhibitory role of the yellow analogs. Our results reveal how stochastically distributed sensory units with modality-specific division of labor serve as separate and opposing input channels for visual guidance. polarization vision rhabdomere insect photoreceptor retinal mosaic pale true false true Angleški jezik Ni določen Članek v reviji 2021-07-08 13:53:48 2021-07-08 13:53:49 2022-09-07 04:14:28 0000-00-00 00:00:00 2019 0 0 Str. 21843-21853 no. 43 Vol. 116 2019 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 591.1 0027-8424 10.1073/pnas.1910807116 5188175 RAZ_Meglic_Andrej_2019.pdf RAZ_Meglic_Andrej_2019.pdf 1 13F8AAB2F757D60E66C30FBEC4DE3248 7b90c2bef63fef005cdc9226b47a3404ebd79e3bf43a3f136a8cc71d563607e9 69f829f9-dfe3-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=145037 https://www.pnas.org/content/116/43/21843 0 2d26948c-dfe3-11eb-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=145036 Biotehniška fakulteta Medicinska fakulteta 0 0 0