Identification of residues controlling transport through the yeast aquaglyceroporin Fps1 using a genetic screen.
Identification of residues controlling transport through the yeast aquaglyceroporin Fps1 using a genetic screen.
复制标题
使用遗传筛选鉴定控制酵母水甘油孔蛋白 Fps1 运输的残基。
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
S. Hohmann
中科院分区：
文献类型：
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作者：
Sara Karlgren;Caroline Filipsson;J. Mullins;R. Bill;Markus J. Tamás;S. Hohmann
水通道蛋白和水甘油机会蛋白介导水和溶质在生物膜上的运输。酿酒酵母Fps1是一种在渗透调节过程中介导可控甘油输出的水甘油oporin。Fps1的转运功能通过渗透变化以一种明显独特的方式快速调节，这种调节需要在长N端和c端延伸的不同区域进行。为了更多地了解控制Fps1的机制，我们已经为过度活跃的Fps1建立了一个遗传筛选，并在14个不同的残基中分离出突变，这些残基都面向细胞内部。其中五个残基位于先前表征的n端调控结构域内，两个突变位于第一个跨膜结构域的途径内。三个突变导致c端截断，证实了先前关于该区域对通道控制的重要性的研究。此外，新的突变确定了通道形成b回路中的两个保守残基，这些残基对通道控制至关重要。对观察到的突变进行的基于结构建模的合理化支持了n端调控域和b环在通道控制中相互作用的观点。我们的发现为进一步的遗传和结构分析提供了一个框架，以更好地理解通过渗透变化控制Fps1功能的机制。
Aquaporins and aquaglyceroporins mediate the transport of water and solutes across biological membranes. Saccharomyces cerevisiae Fps1 is an aquaglyceroporin that mediates controlled glycerol export during osmoregulation. The transport function of Fps1 is rapidly regulated by osmotic changes in an apparently unique way and distinct regions within the long N- and C-terminal extensions are needed for this regulation. In order to learn more about the mechanisms that control Fps1 we have set up a genetic screen for hyperactive Fps1 and isolated mutations in 14 distinct residues, all facing the inside of the cell. Five of the residues lie within the previously characterized N-terminal regulatory domain and two mutations are located within the approach to the first transmembrane domain. Three mutations cause truncation of the C-terminus, confirming previous studies on the importance of this region for channel control. Furthermore, the novel mutations identify two conserved residues in the channel-forming B-loop as critical for channel control. Structural modelling-based rationalization of the observed mutations supports the notion that the N-terminal regulatory domain and the B-loop could interact in channel control. Our findings provide a framework for further genetic and structural analysis to better understand the mechanism that controls Fps1 function by osmotic changes.
影响因子：
56.9
作者：
Fu, DX;Libson, A;Stroud, RM
通讯作者：
Stroud, RM