5OW3

Crystal structure of a C-terminally truncated trimeric ectodomain of the Arabidopsis thaliana gamete fusion protein HAP2

5OW3 の概要

• エントリーDOI: 10.2210/pdb5ow3/pdb
• 分子名称: Protein HAPLESS 2, 2-acetamido-2-deoxy-beta-D-glucopyranose, ZINC ION, ... (6 entities in total)
• 機能のキーワード: gamete fusion protein, class ii fold, hap2, membrane fusion, membrane protein
• 由来する生物種: Arabidopsis thaliana (thale cress)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 58988.40

構造登録者

Fedry, J.,Legrand, P.,Rey, F.A.,Krey, T. (登録日: 2017-08-30, 公開日: 2018-08-22, 最終更新日: 2024-11-20)

主引用文献

Fedry, J.,Forcina, J.,Legrand, P.,Pehau-Arnaudet, G.,Haouz, A.,Johnson, M.,Rey, F.A.,Krey, T.
Evolutionary diversification of the HAP2 membrane insertion motifs to drive gamete fusion across eukaryotes.
PLoS Biol., 16:e2006357-e2006357, 2018

PubMed Abstract: HAPLESS2 (HAP2) is a broadly conserved, gamete-expressed transmembrane protein that was shown recently to be structurally homologous to viral class II fusion proteins, which initiate fusion with host cells via insertion of fusion loops into the host membrane. However, the functional conformation of the HAP2 fusion loops has remained unknown, as the reported X-ray structure of Chlamydomonas reinhardtii HAP2 lacked this critical region. Here, we report a structure-guided alignment that reveals diversification of the proposed HAP2 fusion loops. Representative crystal structures show that in flowering plants, HAP2 has a single prominent fusion loop projecting an amphipathic helix at its apex, while in trypanosomes, three small nonpolar loops of HAP2 are poised to interact with the target membrane. A detailed structure-function analysis of the Arabidopsis HAP2 amphipathic fusion helix defines key residues that are essential for membrane insertion and for gamete fusion. Our study suggests that HAP2 may have evolved multiple modes of membrane insertion to accommodate the diversity of membrane environments it has encountered during eukaryotic evolution.

PubMed: 30102690
DOI: 10.1371/journal.pbio.2006357

実験手法

X-RAY DIFFRACTION (2.75 Å)