Aguilera M, Oliveros M, Martínez-Padrón M, Barbas J A, Ferrús A
Instituto Cajal, Consejo Superior de Investigaciones Científicas, Madrid 28002J, Spain.
Genetics. 2000 Jul;155(3):1231-44. doi: 10.1093/genetics/155.3.1231.
We report the identification and functional characterization of ariadne-1 (ari-1), a novel and vital Drosophila gene required for the correct differentiation of most cell types in the adult organism. Also, we identify a sequence-related gene, ari-2, and the corresponding mouse and human homologues of both genes. All these sequences define a new protein family by the Acid-rich, RING finger, B-box, RING finger, coiled-coil (ARBRCC) motif string. In Drosophila, ari-1 is expressed throughout development in all tissues. The mutant phenotypes are most noticeable in cells that undergo a large and rapid membrane deposition, such as rewiring neurons during metamorphosis, large tubular muscles during adult myogenesis, and photoreceptors. Occasional survivors of null alleles exhibit reduced life span, motor impairments, and short and thin bristles. Single substitutions at key cysteines in each RING finger cause lethality with no survivors and a drastic reduction of rough endoplasmic reticulum that can be observed in the photoreceptors of mosaic eyes. In yeast two-hybrid assays, the protein ARI-1 interacts with a novel ubiquitin-conjugating enzyme, UbcD10, whose sequence is also reported here. The N-terminal RING-finger motif is necessary and sufficient to mediate this interaction. Mouse and fly homologues of both ARI proteins and the Ubc can substitute for each other in the yeast two-hybrid assay, indicating that ARI represents a conserved novel mechanism in development. In addition to ARI homologues, the RBR signature is also found in the Parkinson-disease-related protein Parkin adjacent to an ubiquitin-like domain, suggesting that the study of this mechanism could be relevant for human pathology.
我们报告了阿里阿德涅-1（ari-1）的鉴定及其功能特征，ari-1是一种新的、对成年生物体中大多数细胞类型的正确分化至关重要的果蝇基因。此外，我们鉴定了一个序列相关基因ari-2，以及这两个基因相应的小鼠和人类同源物。所有这些序列通过富含酸性氨基酸、RING指结构、B盒、RING指结构、卷曲螺旋（ARBRCC）基序串定义了一个新的蛋白质家族。在果蝇中，ari-1在所有组织的整个发育过程中都有表达。突变表型在经历大量快速膜沉积的细胞中最为明显，例如变态过程中重新布线的神经元、成虫肌生成过程中的大型管状肌肉以及光感受器。无效等位基因的偶尔存活者表现出寿命缩短、运动障碍以及短而细的刚毛。每个RING指结构中关键半胱氨酸的单取代导致致死，无一存活，并且在嵌合眼的光感受器中可观察到粗面内质网急剧减少。在酵母双杂交试验中，蛋白质ARI-1与一种新的泛素结合酶UbcD10相互作用，其序列也在此报告。N端RING指基序对于介导这种相互作用是必要且充分的。在酵母双杂交试验中，两种ARI蛋白和Ubc的小鼠和果蝇同源物可以相互替代，这表明ARI代表了发育过程中一种保守的新机制。除了ARI同源物外，在帕金森病相关蛋白Parkin中与泛素样结构域相邻处也发现了RBR特征，这表明对该机制的研究可能与人类病理学相关。
