Decoding the network of Trypanosoma brucei proteins that determines sensitivity to apolipoprotein-L1.
Decoding the network of Trypanosoma brucei proteins that determines sensitivity to apolipoprotein-L1.
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DOI：
10.1371/journal.ppat.1006855
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发表时间：
2018-01
期刊：
影响因子：
6.7
通讯作者：
Alsford S
中科院分区：
文献类型：
--
作者：
Currier RB;Cooper A;Burrell-Saward H;MacLeod A;Alsford S
与布氏冈比亚锥虫（Trypanosoma brucei gambiense）和T. B. rhodesiense（人类非洲锥虫病的病原体）、T. B.布氏杆菌被含有载脂蛋白-L1（apoL 1）的人血清锥虫溶解因子（TLF）裂解，使其对人无感染性。虽然TLF 1摄取、apoL 1膜整合和T. B. gambiense和T. B.罗得西亚杆菌apoL 1抗性已经被广泛表征，我们对T. B.布鲁斯是有限的。选择我们的血液T型。B.利用重组apoL 1构建的布氏RNAi文库鉴定了一系列支持apoL 1杀锥虫作用的因子，包括6种假定的泛素修饰物和几种参与膜运输的蛋白质;我们还鉴定了已知的apoL 1敏感性决定簇TbKIFC 1和V-ATPase。其中最突出的新apoL 1敏感性决定因素是一个假定的泛素连接酶。有趣的是，虽然这种泛素连接酶的损失降低了寄生虫对apoL 1的敏感性，但其损失增强了寄生虫对TLF 1主导的正常人血清的敏感性，表明游离和TLF 1结合的apoL 1具有相反的作用模式。事实上，已知的人血清敏感性决定因素p67（溶酶体相关膜蛋白）和组织蛋白酶-L调节剂“半胱氨酸肽酶抑制剂”的缺失对游离apoL 1的敏感性没有影响。我们的研究结果突出了一个复杂的网络蛋白质，影响载脂蛋白1的行动，与我们的理解的抗锥虫作用的人血清的影响。人的锥虫分解血清成分载脂蛋白-L1（apoL 1）的表达以及两个非洲锥虫亚种的对策的伴随进化定义了它们在人类中引起疾病的能力。基因组规模的RNAi筛选鉴定了60多种使非人类感染性锥虫对apoL 1敏感的蛋白质。将这些输出与使用不同选择方法的先前筛选进行比较，提供了对人血清介导的锥虫杀伤作用模式的见解。apoL 1和携带它的锥虫溶解因子（TLF）的有效性取决于寄生虫的内吞系统的摄取、细胞内转运和递送到靶膜。将我们目前的数据与以前的筛选结果进行比较，发现apoL 1能够利用不同的途径进入其靶膜，这取决于它是游离的，还是像在人血清中那样与TLF 1或TLF 2复合。
In contrast to Trypanosoma brucei gambiense and T. b. rhodesiense (the causative agents of human African trypanosomiasis), T. b. brucei is lysed by apolipoprotein-L1 (apoL1)-containing human serum trypanolytic factors (TLF), rendering it non-infectious to humans. While the mechanisms of TLF1 uptake, apoL1 membrane integration, and T. b. gambiense and T. b. rhodesiense apoL1-resistance have been extensively characterised, our understanding of the range of factors that drive apoL1 action in T. b. brucei is limited. Selecting our bloodstream-form T. b. brucei RNAi library with recombinant apoL1 identified an array of factors that supports the trypanocidal action of apoL1, including six putative ubiquitin modifiers and several proteins putatively involved in membrane trafficking; we also identified the known apoL1 sensitivity determinants, TbKIFC1 and the V-ATPase. Most prominent amongst the novel apoL1 sensitivity determinants was a putative ubiquitin ligase. Intriguingly, while loss of this ubiquitin ligase reduces parasite sensitivity to apoL1, its loss enhances parasite sensitivity to TLF1-dominated normal human serum, indicating that free and TLF1-bound apoL1 have contrasting modes-of-action. Indeed, loss of the known human serum sensitivity determinants, p67 (lysosomal associated membrane protein) and the cathepsin-L regulator, ‘inhibitor of cysteine peptidase’, had no effect on sensitivity to free apoL1. Our findings highlight a complex network of proteins that influences apoL1 action, with implications for our understanding of the anti-trypanosomal action of human serum. Expression of the trypanolytic serum component, apolipoprotein-L1 (apoL1), by humans and the concomitant evolution of countermeasures by two African trypanosome sub-species defines their ability to cause disease in humans. A genome-scale RNAi screen identified more than 60 proteins that sensitise non-human infectious trypanosomes to apoL1. Comparing these outputs to previous screens that used different selection approaches provides insights into the mode-of-action of human serum-mediated killing of trypanosomes. The effectiveness of apoL1, and the trypanolytic factors (TLF) that carry it, is dependent on the parasite’s endocytic system for uptake, intracellular transit and delivery to target membranes. Comparing our current data to the outputs from previous screens revealed that apoL1 is able to exploit different routes to access its target membranes, depending on whether it is free or, as in human serum, complexed with TLF1 or TLF2.
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DOI：
10.1126/science.1193032
发表时间：
2010-08-13
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Genovese G;Friedman DJ;Ross MD;Lecordier L;Uzureau P;Freedman BI;Bowden DW;Langefeld CD;Oleksyk TK;Uscinski Knob AL;Bernhardy AJ;Hicks PJ;Nelson GW;Vanhollebeke B;Winkler CA;Kopp JB;Pays E;Pollak MR
通讯作者：
Pollak MR
影响因子：
9.6
作者：
Baker N;de Koning HP;Mäser P;Horn D
通讯作者：
Horn D
影响因子：
2.4
作者：
Alsford S;Kelly JM;Baker N;Horn D
通讯作者：
Horn D
DOI：
10.1073/pnas.1505411112
发表时间：
2015-07-21
影响因子：
11.1
作者：
Baker, Nicola;Hamilton, Graham;Horn, David
通讯作者：
Horn, David
影响因子：
5.2
作者：
Bullard, Whitney;Kieft, Rudo;Hajduk, Stephen L.
通讯作者：
Hajduk, Stephen L.