ジャーナル: Nat Struct Mol Biol / 年: 2023 タイトル: The molecular structure of IFT-A and IFT-B in anterograde intraflagellar transport trains. 著者: Samuel E Lacey / Helen E Foster / Gaia Pigino / 要旨: Anterograde intraflagellar transport (IFT) trains are essential for cilia assembly and maintenance. These trains are formed of 22 IFT-A and IFT-B proteins that link structural and signaling cargos to ...Anterograde intraflagellar transport (IFT) trains are essential for cilia assembly and maintenance. These trains are formed of 22 IFT-A and IFT-B proteins that link structural and signaling cargos to microtubule motors for import into cilia. It remains unknown how the IFT-A/-B proteins are arranged into complexes and how these complexes polymerize into functional trains. Here we use in situ cryo-electron tomography of Chlamydomonas reinhardtii cilia and AlphaFold2 protein structure predictions to generate a molecular model of the entire anterograde train. We show how the conformations of both IFT-A and IFT-B are dependent on lateral interactions with neighboring repeats, suggesting that polymerization is required to cooperatively stabilize the complexes. Following three-dimensional classification, we reveal how IFT-B extends two flexible tethers to maintain a connection with IFT-A that can withstand the mechanical stresses present in actively beating cilia. Overall, our findings provide a framework for understanding the fundamental processes that govern cilia assembly.
全体 : Two IFTB repeats from anterograde intraflagellar transport trains...
全体
名称: Two IFTB repeats from anterograde intraflagellar transport trains within native Chlamydomonas reinhardtii cilia
要素
複合体: Two IFTB repeats from anterograde intraflagellar transport trains within native Chlamydomonas reinhardtii cilia
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超分子 #1: Two IFTB repeats from anterograde intraflagellar transport trains...
超分子
名称: Two IFTB repeats from anterograde intraflagellar transport trains within native Chlamydomonas reinhardtii cilia タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: #1-#13
由来(天然)
生物種: Chlamydomonas reinhardtii (クラミドモナス)
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実験情報
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構造解析
手法
クライオ電子顕微鏡法
解析
サブトモグラム平均法
試料の集合状態
helical array
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試料調製
緩衝液
pH: 7 / 詳細: TAP (Tris-Acetate-Phosphate) Media
凍結
凍結剤: ETHANE
詳細
Chlamydomonas reinhardtii cells applied to quantifoil grids and plunge frozen; cilia project out from cell bodies and traverse holes in the carbon film.
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電子顕微鏡法
顕微鏡
TFS KRIOS
撮影
フィルム・検出器のモデル: FEI FALCON IV (4k x 4k) 平均電子線量: 2.6 e/Å2