Collaborative Research: Diversity of modulation and functional flexibility in small neuronal networks: An evolutionary and mechanistic approach

合作研究：小神经元网络中调制的多样性和功能灵活性：进化和机械方法

• 批准号: 1856370
• 负责人: David Schulz
• 金额: $ 37.21万
• 依托单位: University of Hawaii
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-08-01 至 2021-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1856370&HistoricalAwards=false
• 关键词: Collaborative; Research; Diversity; modulation; functional

Rhythmic movements, such as heartbeat and locomotion, must be flexible to allow animals to alter their behavior in response to changing conditions. Rhythmic movements are controlled by networks of nerve cells that interact with one another to produce patterns of nerve impulses that drive appropriate muscle movements. To alter movement patterns, these neural networks rely on the actions of chemical compounds called neuromodulators; these compounds alter (modulate) the properties and interactions of the cells in the network, thereby enabling them to alter the pattern of movements that are generated by the network. Such alterations include, for example, changes in the speed of the resulting behavior or the coordination of muscles that control different portions of the movement pattern. There is evidence, however, that the extent to which similar networks can be altered ("modulatory capacity") varies among species. This project addresses two fundamental questions related to this variability in modulatory capacity: first, on an evolutionary timescale, what variables determine the extent to which networks can be modulated, and second, what factors/mechanisms underlie differences in modulatory capacity. In addition to addressing these questions using as exemplars the stomatogastric network and the cardiac network in a crab that eats only kelp versus a crab that eats many different kinds of food, the current project also prepares the next generation of scientists by (1) training high school students and undergraduates in a variety of research techniques, as well as in designing experiments and in analyzing and presenting data, and (2) providing continuity and potential expansion of the neuroscience component of a program that engages 7th grade Native Americans in Maine in science to enhance their educational aspirations and success in high school and beyond.This project uses the stomatogastric and cardiac networks of closely related majoid crab species with vastly different dietary diversity to test the hypothesis that modulatory capacity is an important evolutionary substrate for diversity within any given behavior, and to ask what mechanisms underlie differences in modulatory capacity. Current data suggest that the stomatogastric network in Pugettia producta, a species that eats only kelp, is not responsive to many modulators that alter the network in another majoid, Libinia emarginata, which has a highly diverse diet. This project expands the number of neuromodulators tested, as well as examines and compares modulation of the cardiac network in the same species. The investigators use transcriptomics and mass spectrometry to identify native isoforms of peptide modulators in these majoids, then use physiological recordings to compare the modulatory capacities of the Pugettia and Libinia stomatogastric and cardiac neuromuscular systems. The prediction is that modulatory capacity in the Pugettia stomatogastric system is less than that of the opportunistic feeder, but that modulation in systems that are presumably subject to similar demands for flexibility, e.g., the cardiac neuromuscular system, is not markedly different. To examine the mechanisms that underlie changes in modulatory capacity, the investigators use transcriptomics, testing the hypothesis that the mechanism underlying decreased modulatory capacity of the Pugettia stomatogastric system is an absence or decreased abundance of receptors to those modulators. Transcriptomics results are confirmed using qRT-PCR and through expression of the receptors of the two species to compare relative binding affinities.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

有节奏的运动，如心跳和运动，必须灵活，使动物能够改变它们的行为，以应对不断变化的条件。有节奏的运动是由神经细胞网络控制的，神经细胞之间相互作用，产生驱动适当肌肉运动的神经冲动模式。为了改变运动模式，这些神经网络依赖于称为神经调节剂的化合物的作用；这些化合物改变(调节)网络中细胞的属性和相互作用，从而使它们能够改变网络产生的运动模式。这样的改变包括，例如，结果行为的速度或控制运动模式不同部分的肌肉协调的变化。然而，有证据表明，相似网络可以改变的程度(“调节能力”)因物种而异。该项目解决了与调制能力的这种可变性相关的两个基本问题：第一，在进化的时间尺度上，什么变量决定了网络可以被调制的程度，第二，什么因素/机制是调制能力差异的基础。除了以只吃海带的螃蟹和吃多种不同食物的螃蟹的口胃网络和心脏网络作为范例来解决这些问题外，目前的项目还通过以下方式为下一代科学家做好准备：(1)培训高中生和本科生掌握各种研究技术，以及设计实验和分析和展示数据，以及(2)为一个项目的神经科学部分提供连续性和潜在的扩展，该项目让缅因州7年级的美国原住民参与科学，以提高他们在高中和高中以外的教育抱负和成功。该项目使用密切相关的食性多样性的巨蟹物种的口胃和心脏网络来测试这一假设，即调节能力是任何给定行为中多样性的重要进化底物，并询问调节能力差异背后的机制。目前的数据表明，只吃海带的Pugettia Producta物种的口胃网络对许多调节器没有反应，这些调节器改变了另一种食性高度多样化的食性动物Libinia emarginata的口胃网络。该项目扩大了测试的神经调节剂的数量，并检查和比较了同一物种中心脏网络的调制。研究人员使用转录组学和质谱学来鉴定这些乳头虫中天然的多肽调节剂的异构体，然后使用生理记录来比较Pugettia和Libinia口胃和心脏神经肌肉系统的调节能力。预测是Pugettia口胃系统的调节能力比机会性喂食器的调节能力要小，但在可能具有类似灵活性需求的系统中，例如心脏神经肌肉系统，调节能力并没有明显的不同。为了检验调节能力变化背后的机制，研究人员使用转录组学，验证了Pugettia口胃系统调节能力降低的机制是这些调节器的受体缺失或丰度降低的假设。转录组学结果通过qRT-PCR和通过两个物种的受体表达来比较相对结合的亲和力来确认。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Assessment of midgut enteroendocrine peptide complement in the honey bee, Apis mellifera

• DOI: 10.1016/j.ibmb.2019.103257
• 发表时间: 2020-01-01
• 期刊: INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY
• 影响因子: 3.8
• 作者: Christie, Andrew E.

Identification of the molecular components of a putative Jasus edwardsii (Crustacea; Decapoda; Achelata) circadian signaling system

假定的 Jasus edwardsii（甲壳类；十足目；Achelata）昼夜节律信号系统的分子成分的鉴定

• DOI: 10.1007/s10158-020-0236-8
• 发表时间: 2020
• 期刊: Invertebrate Neuroscience
• 作者: Christie, Andrew E.

Filling in the gaps: A reevaluation of the Lygus hesperus peptidome using an expanded de novo assembled transcriptome and molecular cloning

• DOI: 10.1016/j.ygcen.2020.113708
• 发表时间: 2021-01-13
• 期刊: GENERAL AND COMPARATIVE ENDOCRINOLOGY
• 影响因子: 2.7
• 作者: Hull, J. Joe;Gross, Roni J.;Christie, Andrew E.
• 通讯作者: Christie, Andrew E.

In silico analyses suggest the cardiac ganglion of the lobster, Homarus americanus, contains a diverse array of putative innexin/innexin-like proteins, including both known and novel members of this protein family

• DOI: 10.1007/s10158-020-0238-6
• 发表时间: 2020-03-02
• 期刊: INVERTEBRATE NEUROSCIENCE
• 作者: Christie, Andrew E.;Hull, J. Joe;Dickinson, Patsy S.
• 通讯作者: Dickinson, Patsy S.

Identification of putative neuropeptidergic signaling systems in the spiny lobster, Panulirus argus

• DOI: 10.1007/s10158-020-0235-9
• 发表时间: 2020-01-24
• 期刊: INVERTEBRATE NEUROSCIENCE
• 作者: Christie, Andrew E.