8APO

Structure of the mitochondrial ribosome from Polytomella magna with tRNAs bound to the A and P sites

これはPDB形式変換不可エントリーです。

8APO の概要

• エントリーDOI: 10.2210/pdb8apo/pdb
• 関連するPDBエントリー: 8A22 8APN
• EMDBエントリー: 15577
• 分子名称: mtLSU-1, uL2m, mS112, ... (125 entities in total)
• 機能のキーワード: mitoribosome, ribosome, mitochondria, polytomella, fragmentation, rrna, evolution, translation
• 由来する生物種: Polytomella magna; 詳細
• タンパク質・核酸の鎖数: 122
• 化学式量合計: 2867515.92

構造登録者

Tobiasson, V.,Berzina, I.,Amunts, A. (登録日: 2022-08-10, 公開日: 2023-06-21, 最終更新日: 2024-10-16)

主引用文献

Tobiasson, V.,Berzina, I.,Amunts, A.
Structure of a mitochondrial ribosome with fragmented rRNA in complex with membrane-targeting elements.
Nat Commun, 13:6132-6132, 2022

PubMed Abstract: Mitoribosomes of green algae display a great structural divergence from their tracheophyte relatives, with fragmentation of both rRNA and proteins as a defining feature. Here, we report a 2.9 Å resolution structure of the mitoribosome from the alga Polytomella magna harbouring a reduced rRNA split into 13 fragments. We found that the rRNA contains a non-canonical reduced form of the 5S, as well as a permutation of the LSU domain I. The mt-5S rRNA is stabilised by mL40 that is also found in mitoribosomes lacking the 5S, which suggests an evolutionary pathway. Through comparison to other ribosomes with fragmented rRNAs, we observe that the pattern is shared across large evolutionary distances, and between cellular compartments, indicating an evolutionary convergence and supporting the concept of a primordial fragmented ribosome. On the protein level, eleven peripherally associated HEAT-repeat proteins are involved in the binding of 3' rRNA termini, and the structure features a prominent pseudo-trimer of one of them (mL116). Finally, in the exit tunnel, mL128 constricts the tunnel width of the vestibular area, and mL105, a homolog of a membrane targeting component mediates contacts with an inner membrane bound insertase. Together, the structural analysis provides insight into the evolution of the ribosomal machinery in mitochondria.

PubMed: 36253367
DOI: 10.1038/s41467-022-33582-5

実験手法

ELECTRON MICROSCOPY (3.2 Å)