Control of assembly of extra-axonemal structures: the paraflagellar rod of trypanosomes
Control of assembly of extra-axonemal structures: the paraflagellar rod of trypanosomes
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DOI：
10.1101/2019.12.17.879841
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发表时间：
2019-12
期刊：
影响因子：
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通讯作者：
A. A. Alves-A.;Maria J. R. Bezerra;W. de Souza;S. Vaughan;N. Cunha-e-Silva;J. Sunter
中科院分区：
文献类型：
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作者：
A. A. Alves-A.;Maria J. R. Bezerra;W. de Souza;S. Vaughan;N. Cunha-e-Silva;J. Sunter
真核生物鞭毛是基于微管的复杂细胞器，在许多生物体中存在轴突外结构，包括哺乳动物精子的外层致密纤维和锥虫的鞭毛旁杆（PFR）。鞭毛组装是一个复杂的过程，发生在细胞质、过渡纤维过渡区和鞭毛三个主要隔室之间。它从蛋白质成分的翻译开始，然后是它们的分类和运输到鞭毛，运输到组装位点，然后结合。鞭毛由500多种蛋白质组成；控制轴轴组件组装的原则相对清晰。然而，轴突外结构组装过程的协调和位置尚不清楚。我们已经在布鲁氏菌中发现了PFR形成所需的两种细胞质蛋白，PFR组装因子1和2。PFR- af1或PFR- af2的缺失都会显著破坏PFR的形成，并导致主要PFR蛋白的数量减少。PFR形成所需的细胞质因子的存在与跨多个隔室促进轴突组装的过程的概念一致，这可能是轴突外结构组装的共同主题。真核生物鞭毛是复杂的细胞器。在许多生物体中存在轴突外结构，包括锥虫鞭毛旁杆。我们已经发现两种细胞质蛋白是鞭毛旁杆形成所必需的。
Eukaryotic flagella are complex microtubule based organelles and in many organisms there are extra-axonemal structures present, including the outer dense fibres of mammalian sperm and the paraflagellar rod (PFR) of trypanosomes. Flagellum assembly is a complex process occurring across three main compartments, the cytoplasm, the transition fibre-transition zone, and the flagellum. It begins with translation of protein components, followed by their sorting and trafficking into the flagellum, transport to the assembly site and then incorporation. Flagella are formed from over 500 proteins; the principles governing axonemal component assembly are relatively clear. However, the coordination and sites of extra-axonemal structure assembly processes are less clear. We have discovered two cytoplasmic proteins in T. brucei that are required for PFR formation, PFR assembly factors 1 and 2. Deletion of either PFR-AF1 or PFR-AF2 dramatically disrupted PFR formation and caused a reduction in the amount of major PFR proteins. The presence of cytoplasmic factors required for PFR formation aligns with the concept of processes occurring across multiple compartments to facilitate axoneme assembly and this is likely a common theme for extra-axonemal structure assembly. Summary statement Eukaryotic flagella are complex organelles. In many organisms there are extra-axonemal structures including the trypanosome paraflagellar rod. We have discovered two cytoplasmic proteins that are required for paraflagellar rod formation.