Department of Biochemistry II, Georg-August University, Göttingen, Germany.
Autophagy. 2013 Jan;9(1):106-7. doi: 10.4161/auto.22400. Epub 2012 Oct 15.
PROPPINs are a family of PtdIns3P and PtdIns(3,5)P 2-binding proteins. The crystal structure now unravels the presence of two distinct phosphoinositide-binding sites at the circumference of the seven bladed β-propeller. Mutagenesis analysis of the binding sites shows that both are required for normal membrane association and autophagic activities. We identified a set of evolutionarily conserved basic and polar residues within both binding pockets, which are crucial for phosphoinositide binding. We expect that membrane association of PROPPINs is further stabilized by membrane insertions and interactions with other proteins.
PROPPINs 是一类 PtdIns3P 和 PtdIns(3,5)P2 结合蛋白。该晶体结构现在揭示了在七叶β-螺旋桨的圆周上存在两个不同的磷酸肌醇结合位点。结合位点的突变分析表明，这两个位点对于正常的膜结合和自噬活性都是必需的。我们在两个结合口袋内鉴定了一组进化上保守的碱性和极性残基，它们对磷酸肌醇结合至关重要。我们预计 PROPPINs 的膜结合将通过膜插入和与其他蛋白质的相互作用进一步稳定。
