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Abstract Recent years have led to increased effort to describe and understand the peripheral nervous system and its influence on central mechanisms and behavior in gastropod molluscs. This study revealed that an antibody raised against keyhole limpet hemocyanin (KLH) cross‐reacts with an antigen(s) found extensively in both the central and the peripheral nervous systems ofBiomphalaria alexandrina. The results revealed KLH‐like immunoreactive (LIR) neurons in the cerebral, pedal, buccal, left pleural, right parietal, and visceral ganglion within the CNS with fibers projecting throughout all the peripheral nerves. Numerous KLH‐LIR peripheral sensory neurons located in the foot, lips, tentacles, mantle, esophagus, and penis exhibited a bipolar morphology with long tortuous dendrites. KLH‐LIR cells were also present in the eye and statocyst, thus suggesting the labeling of multiple sensory modalities/cell types. KLH‐LIR cells did not co‐localize with tyrosine hydroxylase (TH)‐LIR cells, which have previously been described in this and other gastropods. The results thus provide descriptions of thousands of peripheral sensory neurons, not previously described in detail. Future research should seek to pair sensory modalities with peripheral cell type and attempt to further elucidate the nature of KLH‐like reactivity. These findings also emphasize the need for caution when analyzing results obtained through use of antibodies raised against haptens conjugated to carrier proteins, suggesting the need for stringent controls to help limit potential confounds caused by cross‐reactivity. In addition, this study is the first to describe neuronal cross‐reactivity with KLH inBiomphalaria, which could provide a substrate for host‐parasite interactions with a parasitic trematode,Schistosoma.
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Cellular‐resolution gene expression mapping reveals organization in the head ganglia of the gastropod, Berghia stephanieae
Abstract Gastropod molluscs such asAplysia,Lymnaea, andTritoniahave been important for determining fundamental rules of motor control, learning, and memory because of their large, individually identifiable neurons. Yet only a small number of gastropod neurons have known molecular markers, limiting the ability to establish brain‐wide structure–function relations. Here we combine high‐throughput, single‐cell RNA sequencing with in situ hybridization chain reaction in the nudibranchBerghia stephanieaeto identify and visualize the expression of markers for cell types. Broad neuronal classes were characterized by genes associated with neurotransmitters, like acetylcholine, glutamate, serotonin, and GABA, as well as neuropeptides. These classes were subdivided by other genes including transcriptional regulators and unannotated genes. Marker genes expressed by neurons and glia formed discrete, previously unrecognized regions within and between ganglia. This study provides the foundation for understanding the fundamental cellular organization of gastropod nervous systems.
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- Award ID(s):
- 2227963
- PAR ID:
- 10518212
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Comparative Neurology
- Volume:
- 532
- Issue:
- 6
- ISSN:
- 0021-9967
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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