Genomic Organization and Evolution of Cephalopod Brains

具有复杂大脑的神经系统的起源代表了动物史上的一个重大进化转变。研究人员将测试大脑/记忆进化的替代假说，以确定这些功能是单一来源还是多个来源。章鱼大脑中表达的基因将被研究，并与其他软体动物大脑中表达的基因进行比较。将开发新的方法来评估来自不同动物的基因之间的进化关系，以确定不同的动物群体在大脑发育期间是否使用相同的基因，或者每种动物是否具有一组不同的基因，这些基因在发育期间组织大脑中心。项目成果包括向更广泛的研究社区提供廉价的基因分析技术，并缩短处理周转时间。该项目将为学生提供机会，将研究培训与波多黎各、美属萨摩亚、帕劳和夏威夷的实地海洋生物多样性研究相结合。计划为K-12教师和学生开展外展活动。这个项目将调查来自不同系统发育群体的大脑是否起源于单一的祖先细胞谱系，或者神经元及其形成的大脑是否来自代表多个，可能是9-12个头化事件的不同谱系。三方大脑假说预测，双侧大脑由三个不同的区域组成，这三个区域由一组保守的转录因子Hox、OTx和Pax2/5/6决定，而另一种观点认为，头足类特有的创新可能导致了这一组物种复杂大脑的独立形成。单神经元基因组学和连接性将被用来重建头足类和脊索类大脑中同源细胞群体的进化命运。

The origin of nervous systems with complex brains represents a major evolutionary transition in the history of animals. Investigators will test alternative hypotheses for brain/memory evolution to determine whether these functions have single or multiple origins. Genes expressed in Octopus brains will be studied and compared with genes expressed in the brains of other mollusks. New ways of assessing evolutionary relationships between the genes from the different animals will be developed in order to determine whether different animal groups use the same genes during brain development or whether each type of animal has a different set of genes that organize brain centers during development. Project outcomes include making available to the wider research community inexpensive gene analysis techniques with short processing turn-around times. The project will provide opportunities for students to combine research training with field-based marine biodiversity research in Puerto Rico, American Samoa, Palau, and Hawaii. Outreach activities are planned for K-12 teachers and students. This project will investigate whether brains from diverse phylogenetic groups originate from a single ancestral cell lineage or whether neurons and the brains they form have developed from different lineages representing multiple, perhaps 9-12, cephalization events. The tripartite brain hypothesis predicts that the bilaterian brain is composed of three distinct regions which are determined by a set of conserved transcription factors, Hox, Otx, and Pax2/5/6, whereas an alternate view is that cephalopod-specific innovations may have led to independent formation of the complex brains of species in this group. Single-neuron genomics and connectivity will be used to reconstruct the evolutionary fate of homologous cell populations in cephalopod and chordate brains.