Serotonin-immunoreactivity in the ventral nerve cord of Pycnogonida ᾿support for individually identifiable neurons as ancestral feature of the arthropod nervous system

详细信息    查看全文

• 作者：Georg Brenneis ; Gerhard Scholtz
• 关键词：Sea spiders ; Neuroanatomy ; Neurophylogeny ; Evolution ; 5 ; hydroxytryptamine ; Immunohistochemistry ; Pycnogonum litorale ; Meridionale ; Cilunculus japonicus
• 刊名：BMC Evolutionary Biology
• 出版年：2015
• 出版时间：December 2015
• 年：2015
• 卷：15
• 期：1
• 全文大小：3,961 KB
• 刊物主题：Evolutionary Biology; Animal Systematics/Taxonomy/Biogeography; Entomology; Genetics and Population Dynamics; Life Sciences, general;
• 出版者：BioMed Central
• ISSN：1471-2148

文摘

Background The arthropod ventral nerve cord features a comparably low number of serotonin-immunoreactive neurons, occurring in segmentally repeated arrays. In different crustaceans and hexapods, these neurons have been individually identified and even inter-specifically homologized, based on their soma positions and neurite morphologies. Stereotypic sets of serotonin-immunoreactive neurons are also present in myriapods, whereas in the investigated chelicerates segmental neuron clusters with higher and variable cell numbers have been reported. This led to the suggestion that individually identifiable serotonin-immunoreactive neurons are an apomorphic feature of the Mandibulata. To test the validity of this neurophylogenetic hypothesis, we studied serotonin-immunoreactivity in three species of Pycnogonida (sea spiders). This group of marine arthropods is nowadays most plausibly resolved as sister group to all other extant chelicerates, rendering its investigation crucial for a reliable reconstruction of arthropod nervous system evolution.