PDF(Pubmed)
Abstract：
Trypanosoma cruzi uses various mechanisms to cope with osmotic fluctuations during infection, including the remodeling of organelles such as the contractile vacuole complex (CVC). Little is known about the morphological changes of the CVC during pulsation cycles occurring upon osmotic stress. Here, we investigated the structure-function relationship between the CVC and the flagellar pocket domain where fluid discharge takes place-the adhesion plaque-during the CVC pulsation cycle. Using TcrPDEC2 and TcVps34 overexpressing mutants, known to have low and high efficiency for osmotic responses, we described a structural phenotype for the CVC that matches their corresponding physiological responses. Quantitative tomography provided data on the volume of the CVC and spongiome connections. Changes in the adhesion plaque during the pulsation cycle were also quantified and a dense filamentous network was observed. Together, the results suggest that the adhesion plaque mediates fluid discharge from the central vacuole, revealing new aspects of the osmoregulatory system in T. cruzi.
摘要：
克氏锥虫利用各种机制来应对感染过程中的渗透波动，包括细胞器的重塑，如收缩液泡复合物（CVC）。关于在渗透胁迫下发生的脉动循环期间CVC的形态变化知之甚少。这里,我们研究了CVC搏动周期中发生流体排出的鞭毛袋域-粘连斑块-之间的结构-功能关系。使用TcrPDEC2和TcVps34过表达突变体，已知渗透反应效率低，效率高，我们描述了CVC的结构表型,其与其相应的生理反应相匹配。定量层析成像提供了有关CVC和海绵体连接的体积的数据。还量化了脉动周期中粘连斑块的变化，并观察到了致密的丝状网络。一起,结果表明，粘连斑块介导了中央液泡的液体排出，揭示T.Cruzi渗透调节系统的新方面。
