The Mechanism of Glycine Betaine Mediated Cellular Osmoregulation-Revision 2

甘氨酸甜菜碱介导的细胞渗透压调节机制-修订版 2

• 批准号: 9604679
• 负责人: Sidney Pierce
• 金额: $ 16万
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-06-01 至 1999-10-12
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9604679&HistoricalAwards=false
• 关键词: Mechanism; Glycine; Betaine; Mediated; Cellular

Pierce 9604679 This proposal requests funds to continue a study of the mechanisms that regulate the concentration of the intracellular osmolyte, glycine betaine, in response to high salinity stress. Glycine betaine is an extremely common and important osmolyte in a wide variety of species ranging from bacteria to plants and animals. Although a great deal is known about the salinity-induced regulation of glycine betaine in bacteria, far less is known about its regulation in plants, and even less in animals. The PI had found previously that oysters (Crassostrea virginica) from the Atlantic coast utilize substantial amounts of glycine betaine to regulate intracellular osmotic concentrations following high salinity stress. Conspecific oysters from the Chesapeake Bay have much smaller levels of glycine betaine that do not change following salinity stress and the Bay oysters are not as salinity tolerant. In addition, the PI's previous work has indicated that the basis of this difference in glycine betaine accumulation and salinity tolerance lies within synthetic pathways that reside in the mitochondria. Furthermore, in bacteria and plants, salinity-induced glycine betaine accumulation is regulated by a family of genes that is osmotically-activated. Almost nothing is known about osmotically activated genes in animals. The experiments described in this project propose to exploit the differences between Atlantic and Bay oysters in glycine betaine metabolism to begin to understand how this important, but scarcely studied osmolyte is regulated in animals cells. Further, since all of the Bay oysters are parasitized by the haplosporidian parasite, Perkinsus marinas, which has devastated the Bay oyster fishery, the initial experiments will focus on the possibility that the parasite is causing the biochemical differences between the two oyster groups. The results will contribute a great deal to the understanding of glycine betaine regulation, salinity tolerance mechanis ms, cellular osmoregulation and, perhaps, uncover some of the biochemical consequences of that parasite on oyster metabolism.

皮尔斯9604679 该提案要求资金继续研究调节细胞内渗透压物质甘氨酸甜菜碱浓度的机制，以应对高盐胁迫。甘氨酸甜菜碱是从细菌到植物和动物的各种物种中极其常见和重要的渗透剂。尽管人们对细菌中甘氨酸甜菜碱的盐诱导调节有很多了解，但对其在植物中的调节知之甚少，在动物中更是如此。PI先前发现，来自大西洋海岸的牡蛎（Crassostreavirginica）在高盐度胁迫后利用大量的甘氨酸甜菜碱来调节细胞内渗透浓度。来自切萨皮克湾的同种牡蛎的甘氨酸甜菜碱水平要小得多，在盐度胁迫后不会改变，海湾牡蛎不耐盐。此外，PI以前的工作表明，甘氨酸甜菜碱积累和耐盐性差异的基础在于线粒体中的合成途径。 此外，在细菌和植物中，盐诱导的甘氨酸甜菜碱积累是由一个家族的基因，是植物激活的调控。几乎没有人知道动物中的免疫激活基因。本项目中描述的实验提出利用大西洋牡蛎和海湾牡蛎在甘氨酸甜菜碱代谢方面的差异，开始了解这种重要但几乎没有研究的渗透剂在动物细胞中是如何调节的。 此外，由于所有的海湾牡蛎都被单孢子虫寄生虫Perkinsus marinas寄生，它破坏了海湾牡蛎渔业，最初的实验将集中在寄生虫导致两个牡蛎群体之间的生化差异的可能性上。 这些结果将有助于了解甜菜碱调节、耐盐机制、细胞代谢调节，并可能揭示该寄生虫对牡蛎代谢的某些生化后果。