Elzbieta Pyza

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Daily rhythms of changes in axon size and shape are seen in two types of monopolar cell-L1 and L2-that are unique cells within each of the modules or cartridges of the first optic neuropil or lamina in the fly's optic lobe. In the fruit fly Drosophila, L1 and L2's axons swell at the beginning of both day and night, with larger size increases occurring at(More)
Photoreceptors of the fly's compound eye generally show no very obvious daily or circadian rhythms, a lack which prompted us to examine whether their function might be regulated not in the retina, but at the site of transmission in the first visual neuropile, or lamina. Here, photoreceptor terminals (R1-R6) are reciprocally interconnected with one class of(More)
Axon calibre in monopolar cells L1 and L2 of the fly's lamina can change dynamically. Swelling by day, L2 exhibits a daily rhythm of changing size apparntly mediated by wide-field LBO5HT and PDH cells. L1/L2 axon profiles were measured planimetrically in the housefly, Musca domestica, from 1 μm cross sections. Four hours after injecting 80–100 nl of 1.25 ×(More)
Two types of monopolar cell interneurons, each with a single representative in every unit cartridge of the first optic neuropil, or lamina, of the housefly's optic lobe, have axons that undergo cyclical changes in diameter. The axons are largest during the beginning of day in a normal LD light cycle and smallest during the middle of the night, changes that(More)
In the visual system of Drosophila melanogaster, two classes of interneurons in the first optic neuropil, or lamina, the monopolar cells L1 and L2, show rhythmic circadian changes in the shape and size of their axons. In the present study we have used the GAL4-UAS system to target the GFP expression to the L2 cells in D. melanogaster and to examine(More)
Screening pigment granules occur in the synaptic terminals of photoreceptors in the fly's (Musca domestica, L.) compound eye. The granules resemble ommochrome granules in the overlying photoreceptor cell body. There are also two types of invagination into receptor terminals: capitate projections (from glial cells) and invaginations from neighboring receptor(More)
Considerable progress has recently been reported in locating the cellular basis and molecular mechanisms of the circadian clock in the fruitfly, Drosophila melanogaster. To advance beyond the clock, towards the outputs that lie between the clock itself and the circadian rhythms in behaviour that it regulates, will present new challenges. This is because(More)
The visual system of the fly's compound eye undergoes a number of cyclical day/night changes that have a circadian basis. Such responses are seen in the synaptic terminals of the photoreceptors and in their large monopolar-cell interneurons in the first optic neuropile, or lamina. These changes include, in the photoreceptor terminals, rhythms in the numbers(More)
The structure of neurons changes during development and in response to injury or alteration in sensory experience. Changes occur in the number, shape, and dimensions of dendritic spines together with their synapses. However, precise data on these changes in response to learning are sparse. Here, we show using quantitative transmission electron microscopy(More)
Long-term memory (LTM) formation has been linked with functional strengthening of existing synapses and other processes including de novo synaptogenesis. However, it is unclear whether synaptogenesis can contribute to LTM formation. Here, using α-calcium/calmodulin kinase II autophosphorylation-deficient (T286A) mutants, we demonstrate that when functional(More)