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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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The Voltage-Gated Sodium Channel in Drosophila , Para, Localizes to Dendrites As Well As Axons in Mechanosensitive Chordotonal Neurons
Abstract The fruit flyDrosophila melanogasterhas provided important insights into how sensory information is transduced by transient receptor potential (TRP) channels in the peripheral nervous system (PNS). However, TRP channels alone have not been able to completely model mechanosensitive transduction in mechanoreceptive chordotonal neurons (CNs). Here, we show that, in addition to TRP channels, the sole voltage-gated sodium channel (NaV) inDrosophila, Para, is localized to the dendrites of CNs. Para is localized to the distal tip of the dendrites in all CNs, from embryos to adults, and is colocalized with the mechanosensitive TRP channels No mechanoreceptor potential C (NompC) and Inactive/Nanchung (Iav/Nan). Para localization also demarcates spike initiation zones (SIZs) in axons and the dendritic localization of Para is indicative of a likely dendritic SIZ in fly CNs. Para is not present in the dendrites of other peripheral sensory neurons. In both multipolar and bipolar neurons in the PNS, Para is present in a proximal region of the axon, comparable to the axonal initial segment (AIS) in vertebrates, 40–60 μm from the soma in multipolar neurons and 20–40 μm in bipolar neurons. Whole-cell reduction ofparaexpression using RNAi in CNs of the adult Johnston’s organ (JO) severely affects sound-evoked potentials (SEPs). However, the duality of Para localization in the CN dendrites and axons identifies a need to develop resources to study compartment-specific roles of proteins that will enable us to better understand Para’s role in mechanosensitive transduction.
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- Award ID(s):
- 2037828
- PAR ID:
- 10423155
- Publisher / Repository:
- DOI PREFIX: 10.1523
- Date Published:
- Journal Name:
- eneuro
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2373-2822
- Page Range / eLocation ID:
- Article No. ENEURO.0105-23.2023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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