Transgenesis enables mapping of segmental ganglia in the leech Helobdella austinensis
Research article published in The Journal of experimental biology (2024)
Abstract
The analysis of how neural circuits function in individuals and change during evolution is simplified by the existence of neurons identified as homologous within and across species. Invertebrates, including leeches, have been used for these purposes in part because their nervous systems comprise a high proportion of identified neurons, but technical limitations make it challenging to assess the full extent to which assumptions of stereotypy hold true. Here, we introduce Minos plasmid-mediated transgenesis as a tool for introducing transgenes into the embryos of the leech Helobdella austinensis (Spiralia; Lophotrochozoa; Annelida; Clitellata; Hirudinida; Glossiphoniidae). We identified an enhancer driving pan-neuronal expression of markers, including histone2B:mCherry, which allowed us to enumerate neurons in segmental ganglia. Unexpectedly, we found that the segmental ganglia of adult transgenic H. austinensis contain fewer and more variable numbers of neurons than in previously examined leech species.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.
Why This Matters for Hirudotherapy
This basic-science study introduced Minos plasmid-mediated transgenesis into embryos of the leech Helobdella austinensis (a glossiphoniid annelid in the order Hirudinida), used a pan-neuronal enhancer driving fluorescent markers (including histone2B:mCherry) to enumerate neurons in segmental ganglia, and unexpectedly found that adult transgenic animals had fewer and more variable neuron numbers than previously examined leech species. It is genuinely about a leech, but as a developmental-neuroscience tool paper on a non-bloodfeeding model organism — it illuminates the comparative biology of the broader leech clade and demonstrates emerging genetic tools, not the salivary secretome or any therapeutic application. Caveat: this is preclinical/foundational invertebrate research with no clinical or hirudotherapy outcome; its value to ASH is contextual (leech comparative biology) rather than evidentiary for patient care.
Citation
Transgenesis enables mapping of segmental ganglia in the leech Helobdella austinensis.
Kuo et al. · The Journal of experimental biology, 2024
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