Nanda, I. | Search bioRxiv

bioRxiv2025

Duration discrimination in the bumblebee Bombus terrestris

The ability to process temporal information is crucial for animal activities like foraging, mating, and predator avoidance. While circadian rhythms have been extensively studied, there is limited knowledge regarding how insects process durations in the range of seconds and sub-seconds. This study aimed to assess bumblebees (Bombus terrestris) ability to differentiate the durations of flashing lights, and use this information in a free-foraging task. Bees were trained to associate either the long or short-duration stimulus with a sugar reward versus an unpalatable solution until reaching a criterion, and then tested without sucrose solution with the same stimuli. In Experiment 1, we tested the ability to discriminate between a long stimulus (2.5 or 5 seconds) vs a short stimulus (0.5 or 1 second). The bees learned to discriminate between the two stimuli. To check whether bees solve the task without using the absolute difference in proximal stimulation as a cue, we ran a second experiment. In Experiment 2, the flashing stimuli were presented for the same total amount of time in a cycle. Bees could discriminate between durations even when the overall amount of stimulation in each presentation cycle was the same. This shows general learning abilities in bumblebees, that can discriminate seconds/subseconds intervals in visual flashing stimuli. This reveals an insects ability to use non-naturalistic stimuli and temporal cues in free foraging.

animal behavior and cognition↗

bioRxiv2019

Biallelic TANGO1 mutations cause a novel syndromal disease due to hampered cellular collagen secretion

The transport and Golgi organization 1 (TANGO1) family proteins have been shown to play pivotal roles in the secretory pathway. Full length TANGO1 is a transmembrane protein localised at endoplasmic reticulum exit sites (ERES), where it binds bulky cargo within the ER lumen and recruits membranes from the ER Golgi intermediate compartment (ERGIC) to create an exit route for their export. Tango1 knockout mice display a global collagen secretion defect and perinatal lethality. Here we report the first TANGO1-associated syndrome in humans, which mainly manifests in a collagenopathy. A synonymous substitution that results in exon 8 skipping in most mRNA molecules, ultimately leading to a truncated TANGO1 protein was identified as the disease-causing mutation. The four homozygously affected sons of a consanguineous family display severe dentinogenesis imperfecta, short stature, various skeletal abnormalities, insulin-dependent diabetes mellitus, sensorineural hearing loss, and mild intellectual disability. Functional studies in HeLa and U2OS cells revealed that the corresponding truncated TANGO1 protein is dispersed in the ER and its expression in cells with intact endogenous TANGO1 impairs cellular collagen I secretion.

genetics↗