A Toxoplasma gondii protein with homology to intracellular type Na⁺/H⁺ exchangers is important for osmoregulation and invasion.
A Toxoplasma gondii protein with homology to intracellular type Na⁺/H⁺ exchangers is important for osmoregulation and invasion.
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DOI：
10.1016/j.yexcr.2011.03.020
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发表时间：
2011-06-10
影响因子：
3.7
通讯作者：
Arrizabalaga, Gustavo
中科院分区：
文献类型：
--
作者：
Francia, Maria E.;Wicher, Sarah;Pace, Douglas A.;Sullivan, Jack;Moreno, Silvia N. J.;Arrizabalaga, Gustavo
专性细胞内寄生虫刚地弓形虫（Toxoplasma gondii）在受感染的生物体中繁殖时暴露于各种生理条件。弓形虫克服环境中这些巨大变化的机制尚不清楚。在酵母和植物中，离子解毒和渗透调节由液泡区室控制。最近在弓形虫中发现了一种新的隔室，称为植物样空泡或空泡隔室（plant-like vacuole or vacuolar compartment，PLV/VAC），它可以保护细胞外速殖子免受盐和其他离子胁迫的伤害。本文报道了T.弓形虫TgNHE 3及其与PLV/VAC质子焦磷酸酶（TgVP 1）的共定位。我们已经创建了TgNHE 3敲除菌株，其对高渗休克和毒性水平的钠更敏感，具有更高的细胞内Ca 2+浓度[Ca 2 +]i，并表现出降低的宿主侵入效率。侵袭缺陷与粘附素TgMIC 2分泌的可测量减少相关。总的来说，我们的研究结果表明，PLV/VAC，具有类似于植物和酵母的液泡室的功能，为寄生虫提供了抵抗离子波动的机制，并可能调节蛋白质运输。
The obligate intracellular parasite Toxoplasma gondii is exposed to a variety of physiological conditions while propagating in an infected organism. The mechanisms by which Toxoplasma overcomes these dramatic changes in its environment are not known. In yeast and plants, ion detoxification and osmotic regulation are controlled by vacuolar compartments. A novel compartment named the plant-like vacuole or vacuolar compartment (PLV/VAC) has recently been described in Toxoplasma gondii, which could potentially protect extracellular tachyzoites against salt and other ionic stresses. Here we report the molecular characterization of the vacuolar type Na+/H+ exchanger in T. gondii, TgNHE3, and its co-localization with the PLV/VAC proton-pyrophosphatase (TgVP1). We have created a TgNHE3 knockout strain, which is more sensitive to hyperosmotic shock and toxic levels of sodium, possesses a higher intracellular Ca2+ concentration [Ca2+]i, and exhibits a reduced host invasion efficiency. The defect in invasion correlates with a measurable reduction in the secretion of the adhesin TgMIC2. Overall, our results suggest that the PLV/VAC, has functions analogous to those of the vacuolar compartments of plants and yeasts, providing the parasite with a mechanism to resist ionic fluctuations, and potentially, regulate protein trafficking.
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DOI：
10.1083/jcb.200309097
发表时间：
2004-06-07
期刊：
The Journal of cell biology
影响因子：
--
作者：
Arrizabalaga G;Ruiz F;Moreno S;Boothroyd JC
通讯作者：
Boothroyd JC
影响因子：
3.3
作者：
Bowers, K;Levi, BP;Stevens, TH
通讯作者：
Stevens, TH
影响因子：
10.7
作者：
Castresana, J
通讯作者：
Castresana, J
影响因子：
11.4
作者：
Luo, SH;Vieira, M;Moreno, SNJ
通讯作者：
Moreno, SNJ
影响因子：
4
作者：
Arrizabalaga, G;Boothroyd, JC
通讯作者：
Boothroyd, JC