Department of Psychology, University of Washington, Seattle, Washington, USA.
Department of Biology, University of Washington, Seattle, Washington, USA.
Brain Behav Evol. 2024;99(3):158-170. doi: 10.1159/000539128. Epub 2024 Apr 30.
The octopus peduncle complex is an agglomeration of neural structures with remarkably diverse functional roles. The complex rests on the optic tract, between the optic lobe and the central brain, and comprises the peduncle lobe proper, the olfactory lobe, and the optic gland. The peduncle lobe regulates visuomotor behaviors, the optic glands control sexual maturation and maternal death, and the olfactory lobe is thought to receive input from the olfactory organ. Recent transcriptomic and metabolomic studies have identified candidate peptide and steroid ligands in the Octopus bimaculoides optic gland.
With gene expression for these ligands and their biosynthetic enzymes, we show that optic gland neurochemistry extends beyond the traditional optic gland secretory tissue and into lobular territories.
A key finding is that the classically defined olfactory lobe is itself a heterogeneous territory and includes steroidogenic territories that overlap with cells expressing molluscan neuropeptides and the synthetic enzyme dopamine beta-hydroxylase.
Our study reveals the neurochemical landscape of the octopus peduncle complex, highlighting the unexpected overlap between traditionally defined regions.
章鱼足复合体是一组具有显著不同功能作用的神经结构聚集体。该复合体位于视束上，位于视叶和中央脑之间，包括足叶本身、嗅叶和视神经腺。足叶调节视觉运动行为，视神经腺控制性成熟和母性死亡，而嗅叶被认为接收来自嗅觉器官的输入。最近的转录组学和代谢组学研究已经在章鱼 bimaculoides 的视神经腺中鉴定出候选肽和类固醇配体。
通过这些配体及其生物合成酶的基因表达，我们表明视神经腺神经化学不仅限于传统的视神经腺分泌组织，还延伸到小叶区域。
一个关键发现是，经典定义的嗅叶本身就是一个异质区域，包括与表达软体动物神经肽和合成酶多巴胺β-羟化酶的细胞重叠的类固醇生成区域。
我们的研究揭示了章鱼足复合体的神经化学景观，突出了传统定义区域之间的意外重叠。
