Friocourt G, Chafey P, Billuart P, Koulakoff A, Vinet M C, Schaar B T, McConnell S K, Francis F, Chelly J
Laboratoire de Génétique et Physiopathologie des retards mentaux, ICGM, INSERM, CHU, Cochin, 24, rue du Faubourg Saint Jacques, Paris, 75014, France.
Mol Cell Neurosci. 2001 Sep;18(3):307-19. doi: 10.1006/mcne.2001.1022.
Doublecortin is a microtubule-associated protein required for normal corticogenesis in the developing brain. We carried out a yeast two-hybrid screen to identify interacting proteins. One of the isolated clones encodes the mu1 subunit of the adaptor complex AP-1 involved in clathrin-dependent protein sorting. We found that Doublecortin also interacts in yeast with mu2 from the AP-2 complex. Mutagenesis and pull-down experiments showed that these interactions were mediated through a tyrosine-based sorting signal (YLPL) in the C-terminal part of Doublecortin. The functional relevance of these interactions was suggested by the coimmunoprecipitation of Doublecortin with AP-1 and AP-2 from mouse brain extracts. This interaction was further supported by RNA in situ hybridization and immunofluorescence studies. Taken together these data indicate that a certain proportion of Doublecortin interacts with AP-1 and/or AP-2 in vivo and are consistent with a potential involvement of Doublecortin in protein sorting or vesicular trafficking.
双皮质素是发育中的大脑正常皮质发生所必需的一种微管相关蛋白。我们进行了酵母双杂交筛选以鉴定相互作用蛋白。其中一个分离的克隆编码参与网格蛋白依赖性蛋白分选的衔接蛋白复合体AP-1的μ1亚基。我们发现双皮质素在酵母中也与AP-2复合体的μ2相互作用。诱变和下拉实验表明,这些相互作用是通过双皮质素C末端基于酪氨酸的分选信号(YLPL)介导的。小鼠脑提取物中双皮质素与AP-1和AP-2的共免疫沉淀表明了这些相互作用的功能相关性。RNA原位杂交和免疫荧光研究进一步支持了这种相互作用。这些数据综合起来表明,一定比例的双皮质素在体内与AP-1和/或AP-2相互作用,这与双皮质素可能参与蛋白分选或囊泡运输是一致的。