FB2025_05 , released December 11, 2025
FB2025_05 , released December 11, 2025
CV Term Report
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General Information
Term photoreceptor cell of Bolwig organ ID (Ontology) FBbt:00007253 (Fly Anatomy)
Definition Photoreceptor cell that is part of a Bolwig's organ. Unlike the photoreceptors of the adult eye, eyelet and ocellus, these photoreceptors do not contain rhabdomeres, but instead have apical surfaces which are folded into numerous horizontal microtubule-containing microvillar-like processes (Green et al., 1993; Hartenstein et al., 2019). These processes are variable in length, diameter and spacing, but align approximately along a ventro-anterior to dorso-posterior axis relative to the body and do not branch (Hartenstein et al., 2019). There are around 12 of these cells per hemisphere and their axons enter the brain ventrolaterally via the Bolwig nerve and terminate in the larval optic neuropil (Larderet et al., 2017). There are two mutually exclusive subtypes, expressing Rh5 or Rh6, both of which are cholinergic and are capable of entraining the molecular clock by light (Keene et al., 2011).[ FlyBase:FBrf0064481 FlyBase:FBrf0213587 FlyBase:FBrf0237760 FlyBase:FBrf0243080 ]
Also Known As "larval photoreceptor neuron" ; "larval PRC" ; "photoreceptor cell of Bolwig's organ"
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VFB:FBbt_00007253
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Records annotated with this term OR any of its CHILD TERMS
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Data Class Field Records
Insertions (FBti)  EXPRESSION_STAGE_TISSUE_POSITION       2
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 Alleles Genes Insertions Constructs
 photoreceptor cell of Bolwig organ (all annotations which use CV term, excluding "NOT" statements)       1      7      2      3
Spanning Tree (Parents/Children)
Only view relationship: 
larval neuron
 |__larval cholinergic neuron________
 |__embryonic/larval sensory neuron__|
 |__larval PNS neuron________________|
sensory neuron                       |
 |__photoreceptor neuron_____________|
 |__embryonic/larval sensory neuron__|
cholinergic neuron                   |
 |__larval cholinergic neuron________|
visual system neuron                 |
 |__photoreceptor neuron_____________|
PNS neuron                           |
 |__larval PNS neuron________________|
somatic cell                         |
 |__sensory organ cell_______________|
                                     photoreceptor cell of Bolwig organ  32 rec.
                                      |__Rh5 photoreceptor of Bolwig organ 10 rec.
                                      |__Rh6 photoreceptor of Bolwig organ 16 rec.
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Is a photoreceptor neuron
sensory organ cell
larval cholinergic neuron
embryonic/larval sensory neuron
larval PNS neuron
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VFB:FBbt_00007253