RRC ID |
79112
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Author |
Chung J, Newman-Smith E, Kourakis MJ, Miao Y, Borba C, Medina J, Laurent T, Gallean B, Faure E, Smith WC.
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Title |
A single oscillating proto-hypothalamic neuron gates taxis behavior in the primitive chordate Ciona.
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Journal |
Curr Biol
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Abstract |
Ciona larvae display a number of behaviors, including negative phototaxis. In negative phototaxis, the larvae first perform short spontaneous rhythmic casting swims. As larvae are cast in a light field, their photoreceptors are directionally shaded by an associated pigment cell, providing a phototactic cue. This then evokes an extended negative taxis swim. We report here that the larval forebrain of Ciona has a previously uncharacterized single slow-oscillating inhibitory neuron (neuron cor-assBVIN78) that projects to the midbrain, where it targets key interneurons of the phototaxis circuit known as the photoreceptor relay neurons. The anatomical location, gene expression, and oscillation of cor-assBVIN78 suggest homology to oscillating neurons of the vertebrate hypothalamus. Ablation of cor-assBVIN78 results in larvae showing extended phototaxis-like swims, even in the absence of phototactic cues. These results indicate that cor-assBVIN78 has a gating activity on phototaxis by projecting temporally oscillating inhibition to the photoreceptor relay neurons. However, in intact larvae, the frequency of cor-assBVIN78 oscillation does not match that of the rhythmic spontaneous swims, indicating that the troughs in oscillations do not themselves initiate swims but rather that cor-assBVIN78 may modulate the phototaxis circuit by filtering out low-level inputs while restricting them temporally to the troughs in inhibition.
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Volume |
33(16)
|
Pages |
3360-3370.e4
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Published |
2023-8-21
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DOI |
10.1016/j.cub.2023.06.080
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PII |
S0960-9822(23)00866-7
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PMID |
37490920
|
PMC |
PMC10528541
|
MeSH |
Animals
Ciona* / physiology
Ciona intestinalis*
Hypothalamus
Larva / physiology
Neurons / physiology
Photoreceptor Cells / physiology
|
Resource |
C.intestinalis / (O.japonicus) |
Tg[MiCivGATK]2 |