Institute of Medical Biochemistry-Center for Molecular Biology of Inflammation, University of Münster, Von-Esmarch-Str. 56, D-48149 Münster, Germany.
Organic Chemistry Institute, University of Münster, Corrensstrasse 40, D-48149 Münster, Germany.
Cells. 2020 May 8;9(5):1169. doi: 10.3390/cells9051169.
Annexin A2 (AnxA2) is a cytosolic Ca regulated membrane binding protein that can induce lipid domain formation and plays a role in exocytosis and endocytosis. To better understand the mode of annexin-membrane interaction, we analyzed membrane-bound AnxA2 assemblies by employing a novel 3-armed chemical crosslinker and specific AnxA2 mutant proteins. Our data show that AnxA2 forms crosslinkable oligomers upon binding to membranes containing negatively charged phospholipids. AnxA2 mutants with amino acid substitutions in residues predicted to be involved in lateral protein-protein interaction show compromised oligomer formation, albeit still being capable of binding to negatively charged membranes in the presence of Ca. These results suggest that lateral protein-protein interactions are involved in the formation of AnxA2 clusters on a biological membrane.
膜联蛋白 A2（AnxA2）是一种细胞质钙离子调节的膜结合蛋白，可诱导脂质域形成，并在胞吐和胞吞作用中发挥作用。为了更好地理解膜联蛋白与膜的相互作用模式，我们采用新型三臂化学交联剂和特异性膜联蛋白 A2 突变蛋白分析了膜结合的膜联蛋白 A2 组装体。我们的数据表明，膜联蛋白 A2 在与含有负电荷磷脂的膜结合时会形成可交联的寡聚物。尽管在 Ca 存在的情况下仍能与带负电荷的膜结合，但预测在侧链蛋白-蛋白相互作用中涉及的残基发生氨基酸取代的膜联蛋白 A2 突变体的寡聚体形成能力受损。这些结果表明，侧链蛋白-蛋白相互作用参与了生物膜上膜联蛋白 A2 簇的形成。
