Evolutionary origins of coordination: physiological and molecular studies on sponges (Porifera)

协调的进化起源：海绵（Porifera）的生理和分子研究

• 批准号: 222863-2011
• 负责人: Leys, Sally
• 金额: $ 4.88万
• 依托单位: University of Alberta
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=546665
• 关键词: Evolutionary; origins; coordination; physiological; molecular

Sponges are members of the Porifera, the most primitive extant animals. Sponges are the only group of multicellular animals without a nervous system yet they have various types of slow behaviour that allow them to excrete wastes. The first genome of a sponge is just available, and in it are many molecules that we see in nervous systems in other animals. My students and I are interested in how the sponge pre-nervous systems is organized and functions in their behaviour in the ocean down to the membrane channels involved in sensing signals in the environment and the mechanisms involved in communication between individual cells. This helps us understand how the first nervous systems evolved. We recently found a new sensory cell in sponges which has the potential to clarify how animals sense flow rates in order to control fluid movement, for example in blood capilliaries and kidney tubules. This proposal will investigate a) the molecules involved in signaling between cells in the sponge, and the receptors available to receive signals on cells; b) the molecular mechanisms which sponges use to build the filtration system; and c) the physical parameters of fluid flow that guide the formation of the sponge body. Comparing genes found in sponges with those in animals with the first nervous systems (jellyfish - cnidarians) has highlighted remarkable similarities in the way signaling works in animals even without conventional nerves. Our own work for example has shown that sponges use glutamate and GABA to stimulate and inhibit contractions of tissues, just as in higher animals. Our proposed research program focuses on identifying the regions where signaling occurs between cells (is there a 'proto-synapse'?) and ultimately determining where new cells involved in signaling are produced in developing and in adult sponges.

海绵是多孔动物门的成员，是现存最原始的动物。海绵动物是唯一一种没有神经系统的多细胞动物，但它们有各种各样的缓慢行为，使它们能够排泄废物。海绵的第一个基因组刚刚问世，其中包含许多我们在其他动物神经系统中看到的分子。我和我的学生感兴趣的是海绵前神经系统是如何组织和功能，在他们的行为在海洋中，到膜通道参与感知信号在环境中和机制，参与个别细胞之间的通信。这有助于我们了解第一个神经系统是如何进化的。我们最近在海绵中发现了一种新的感觉细胞，它有可能阐明动物如何感知流速以控制流体运动，例如在毛细血管和肾小管中。该提案将研究a）海绵细胞之间信号传导所涉及的分子，以及细胞上可用于接收信号的受体; B）海绵用于构建过滤系统的分子机制;以及c）引导海绵体形成的流体流动的物理参数。将海绵中发现的基因与具有第一神经系统的动物（水母-刺胞动物）中发现的基因进行比较，突出了即使没有传统神经的动物中信号传导方式的显着相似性。例如，我们自己的研究表明，海绵使用谷氨酸和GABA来刺激和抑制组织收缩，就像高等动物一样。我们提出的研究计划重点是确定细胞之间发生信号传导的区域（是否存在“原突触”？）并最终确定在发育和成年海绵中产生信号的新细胞。