Several forms of callitachykinins are distributed in the central nervous system and intestine of the blowfly <i>Calliphora vomitoria</i>

The Madeira cockroach Rhyparobia maderae is a nocturnal insect and a prominent model organism for the study of circadian rhythms. Its master circadian clock, controlling circadian locomotor activity and sleep-wake cycles, is located in the accessory medulla of the optic lobe. For a better understanding of brain regions controlled by the circadian clock and brain organization of this insect in general, we created a three-dimensional (3D) reconstruction of all neuropils of the cerebral ganglia based on anti-synapsin and anti-γ-aminobutyric acid immunolabeling of whole mount brains.Forty-nine major neuropils were identified and three-dimensionally reconstructed.Single-cell dye fills complement the data and provide evidence for distinct subdivisions of certain brain areas. Most neuropils defined in the fruit fly Drosophila melanogaster could be distinguished in the cockroach as well. However, some neuropils identified in the fruit fly do not exist as distinct entities in the cockroach while others are lacking in the fruit fly. In addition to neuropils, major fiber systems, tracts, and commissures were reconstructed and served as important landmarks separating brain areas. Being a nocturnal insect, R. maderae is an important new species to the growing collection of 3D insect brain atlases and only the second hemimetabolous insect, for which a detailed 3D brain atlas is available. This atlas will be highly valuable for an evolutionary comparison of insect brain organization and will greatly facilitate addressing brain areas that are supervised by the circadian clock.

Section: Methodsmentioning

confidence: 99%

3D‐atlas of the brain of the cockroach Rhyparobia maderae

Althaus

Jahn

Massah

et al. 2022

“…It was raised in rabbit against the full LomTK II peptide (APLSGFYGVR‐NH 2 ) (Veenstra et al., 1995). ELISA with synthetic LomTK I and II and callitachykinins I and II as antigens demonstrated specificity (Nässel et al., 1995). In S. gregaria , immunostaining was completely abolished by preadsorption of the antiserum with 10 µmol L −1 synthetic LomTK II (Vitzthum & Homberg, 1998).…”

Section: Methodsmentioning

confidence: 99%

A three‐dimensional atlas of the honeybee central complex, associated neuropils and peptidergic layers of the central body

Hensgen

Tschirner

Beetz

et al. 2022

The central complex (CX) in the brain of insects is a highly conserved group of midlinespanning neuropils consisting of the upper and lower division of the central body, the protocerebral bridge, and the paired noduli. These neuropils are the substrate for a number of behaviors, most prominently goal-oriented locomotion. Honeybees have been a model organism for sky-compass orientation for more than 70 years, but there is still very limited knowledge about the structure and function of their CX. To advance and facilitate research on this brain area, we created a high-resolution threedimensional atlas of the honeybee's CX and associated neuropils, including the posterior optic tubercles, the bulbs, and the anterior optic tubercles. To this end, we developed a modified version of the iterative shape averaging technique, which allowed us to achieve high volumetric accuracy of the neuropil models. For a finer definition of spatial locations within the central body, we defined layers based on immunostaining against the neuropeptides locustatachykinin, FMRFamide, gastrin/cholecystokinin, and allatostatin and included them into the atlas by elastic registration. Our honeybee CX atlas provides a platform for future neuroanatomical work.

“…Enzyme‐linked immunosorbent assay (ELISA) with synthetic LomTK‐I and ‐II and callitachykinins I and II as antigens was used by Nässel et al. (1995) to test the specificity of the antiserum. Cross‐reaction of the antiserum was found with all four tachykinins, with a slightly higher affinity to the LomTKs.…”

Section: Methodsmentioning

confidence: 99%

“…Immunostaining with the biotinylated anti-LomTK-II antiserum revealed the same staining pattern as the nonbiotinylated antiserum (Vitzthum & Homberg, 1998). Enzyme-linked immunosorbent assay (ELISA) with synthetic LomTK-I and -II and callitachykinins I and II as antigens was used by Nässel et al (1995) to test the specificity of the antiserum. Cross-reaction of the antiserum was found with all four tachykinins, with a slightly higher affinity to the LomTKs.…”

Section: Antibody Characterizationmentioning

confidence: 96%

Myoinhibitory peptides in the central complex of the locust Schistocerca gregaria and colocalization with locustatachykinin‐related peptides

Hensgen

Dippel

Hümmert

et al. 2022

The central complex in the brain of insects provides a neural network for sensorimotor processing that is essential for spatial navigation and locomotion and plays a role in sleep control. Studies on the neurochemical architecture of the central complex have been performed especially in the fruit fly Drosophila melangoaster and the desert locust, Schistocerca gregaria. In several insect species, myoinhibitory peptides (MIPs) are involved in circadian control and sleep‐wake regulation. To identify neurons that might underlie these functions, we investigated the distribution of MIPs in the central complex of the locust. In silico transcript analysis suggests the presence of eight different MIPs in the desert locust. Through immunolabeling, we identified five systems of central‐complex neurons that express MIP‐like peptides. Two systems constitute columnar neurons of the protocerebral bridge and the lower division of the central body, while the other three systems are columnar neurons (two systems) and tangential neurons (one system) of the upper division of the central body. The innervation pattern and cell count of two systems of columnar neurons revealed the existence of 18 instead of 16 columns of the protocerebral bridge. Immunostaining of preparations containing intracellularly stained single cells allowed us to further specify subtypes of labeled columnar neurons. Double‐label experiments showed that three systems of MIP‐immunostained columnar neurons are also locustatachykinin‐immunoreactive. No colocalization was found with serotonin immunostaining. The data provide novel insights into the architecture of the locust central complex and suggest that MIPs play a prominent role within the central‐complex network.