Kipreos E T, Pagano M
Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA.
Genome Biol. 2000;1(5):REVIEWS3002. doi: 10.1186/gb-2000-1-5-reviews3002. Epub 2000 Nov 10.
The F-box is a protein motif of approximately 50 amino acids that functions as a site of protein-protein interaction. F-box proteins were first characterized as components of SCF ubiquitin-ligase complexes (named after their main components, Skp I, Cullin, and an F-box protein), in which they bind substrates for ubiquitin-mediated proteolysis. The F-box motif links the F-box protein to other components of the SCF complex by binding the core SCF component Skp I. F-box proteins have more recently been discovered to function in non-SCF protein complexes in a variety of cellular functions. There are 11 F-box proteins in budding yeast, 326 predicted in Caenorhabditis elegans, 22 in Drosophila, and at least 38 in humans. F-box proteins often include additional carboxy-terminal motifs capable of protein-protein interaction; the most common secondary motifs in yeast and human F-box proteins are WD repeats and leucine-rich repeats, both of which have been found to bind phosphorylated substrates to the SCF complex. The majority of F-box proteins have other associated motifs, and the functions of most of these proteins have not yet been defined.
F 盒是一种由约50个氨基酸组成的蛋白质基序，作为蛋白质-蛋白质相互作用的位点发挥作用。F 盒蛋白最初被鉴定为 SCF 泛素连接酶复合物的组成部分（以其主要成分 Skp I、Cullin 和一种 F 盒蛋白命名），在该复合物中，它们结合底物以进行泛素介导的蛋白水解。F 盒基序通过结合 SCF 核心成分 Skp I，将 F 盒蛋白与 SCF 复合物的其他成分相连。最近发现，F 盒蛋白在多种细胞功能的非 SCF 蛋白复合物中发挥作用。芽殖酵母中有11种 F 盒蛋白，秀丽隐杆线虫中预测有326种，果蝇中有22种，人类中至少有38种。F 盒蛋白通常包含能够进行蛋白质-蛋白质相互作用的额外羧基末端基序；酵母和人类 F 盒蛋白中最常见的二级基序是 WD 重复序列和富含亮氨酸的重复序列，这两种序列都被发现可将磷酸化底物与 SCF 复合物结合。大多数 F 盒蛋白还有其他相关基序，其中大多数蛋白质的功能尚未明确。
