National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01GM143223
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R01GM152716
米国
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
R35GM130298
米国
引用
ジャーナル: Proc Natl Acad Sci U S A / 年: 2025 タイトル: Intraflagellar transport trains can switch rails and move along multiple microtubules in intact primary cilia. 著者: Shufeng Sun / Biqing Liang / Adam Koplas / Irina Tikhonenko / Maxence Nachury / Alexey Khodjakov / Haixin Sui / 要旨: Structural homeostasis and proper distributions of signaling molecules in cilia require a constant flow of cargoes carried by intraflagellar transport (IFT) trains in both anterograde and retrograde ...Structural homeostasis and proper distributions of signaling molecules in cilia require a constant flow of cargoes carried by intraflagellar transport (IFT) trains in both anterograde and retrograde directions within the thin, long ciliary shafts. In the motile cilium framework, the nine microtubule doublets of the same length serve as the transportation rails, and a preferential association to the two subtubules of the microtubule doublets prevents collisions among the IFT trains that move in opposite directions. However, this mechanism is incompatible with the primary cilia structure, where most of the nine microtubule doublets terminate in the ciliary shafts-only several of them reach the ciliary tip and only in a singlet form. Here, we demonstrate that anterograde and retrograde trains in primary cilia interact with both subtubules of the microtubule doublets without apparent preference. They can switch microtubules, and they may simultaneously interact with multiple microtubules to facilitate their movement. This architecture makes the collisions inevitable, and live-cell recordings reveal that anterograde and retrograde trains tend to pause when they come into direct contact. We also find that the velocity of the train's movement often changes after the pause. Thus, the motion behaviors of IFT trains in primary cilia are distinctive from those of motile cilia, and our data offer an essential foundation for understanding proper signaling molecule distributions in primary cilia.
pH: 7.4 / 構成要素 - 濃度: 1.0 X / 構成要素 - 式: PBS / 構成要素 - 名称: Phosphate-buffered saline 詳細: NaCl: 137 mM KCl: 2.7 mM Na2HPO4: 10 mM KH2PO4: 1.8 mM
染色
タイプ: POSITIVE / 材質: Uranyl Acetate/Lead Citrate 詳細: Samples were stained first with Uranyl Acetate and then stained with Lead Citrate
糖包埋
材質: SPI-Pon812 詳細: Samples were dehydrated post fixation using an ethanol gradient at RT. Specimens were then back-substituted with acetone. After infiltration with resin the samples were cured.
Specimen is mIMCD3 cells labeled with triple-mNeonGreen-fusion-IFT88.
切片作成
ウルトラミクロトーム - 装置: UC6 / ウルトラミクロトーム - 温度: 293 K / ウルトラミクロトーム - 最終 厚さ: 120 ウルトラミクロトーム - 詳細: The samples in the resin block were sectioned into serial sections with a target thickness of 150nm. Most sections had an actual thickness of around 120nm.
位置合わせマーカー
Manufacturer: sigma / 直径: 15 nm
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電子顕微鏡法
顕微鏡
FEI TECNAI F20
温度
最低: 292.0 K / 最高: 298.0 K
詳細
A Philips high tilt holder was used for data collection purposes
撮影
フィルム・検出器のモデル: TVIPS TEMCAM-F416 (4k x 4k) 平均電子線量: 5.0 e/Å2