Takahashi Naoki, Kuroda Hirofumi, Kuromori Takashi, Hirayama Takashi, Seki Motoaki, Shinozaki Kazuo, Shimada Hiroaki, Matsui Minami
Plant Function Exploration Team, Plant Functional Genomics Research Group, Genomic Sciences Center, RIKEN Yokohama Institute, 1-7-22 Suyehiro-cho, Tsurumi-ku, Yokohama, Kanagawa, 230-0045 Japan.
Plant Cell Physiol. 2004 Jan;45(1):83-91. doi: 10.1093/pcp/pch009.
Specific protein degradation has been observed in several aspects of development and differentiation in many organisms. One example of such proteolysis is regulated by protein polyubiquitination that is promoted by the SCF complex consisting of Skp1, cullin, and an F-box protein. We examined the activities of the Arabidopsis Skp1-related proteins (ASKs). Among 19 annotated ASK genes, we isolated 16 of the corresponding cDNAs (ASK1, 2, 3, 4, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 19), and examined their gene products for interactions with 24 representatives of F-box proteins carrying various classes of the C-terminal domains using the yeast two-hybrid system. As a result, we found diverse binding specificities: ASK1, ASK2, ASK11 and ASK12 interacted well with COI1, FKF1, UFO-like protein, LRR-containing F-box proteins, and other F-box proteins with unknown C-terminal motifs. We also observed specific interaction between F-box proteins and ASK3, ASK9, ASK13, ASK14, ASK16 and ASK18. In contrast, we detected no interaction between any of the 12 ASK proteins and F-box proteins containing CRFA, CRFB or CRFC domains. Both histochemical and RT-PCR analysis of eight ASK genes expression revealed unique expression patterns for the respective genes.
在许多生物体的发育和分化的多个方面都观察到了特定的蛋白质降解。这种蛋白水解的一个例子是由由Skp1、cullin和一个F-box蛋白组成的SCF复合体促进的蛋白质多聚泛素化所调控。我们检测了拟南芥Skp1相关蛋白（ASKs）的活性。在19个注释的ASK基因中，我们分离出了16个相应的cDNA（ASK1、2、3、4、7、8、9、10、11、12、13、14、16、17、18、19），并使用酵母双杂交系统检测了它们的基因产物与24种携带不同类型C末端结构域的F-box蛋白代表的相互作用。结果，我们发现了多种结合特异性：ASK1、ASK2、ASK11和ASK12与COI1、FKF1、类UFO蛋白、含LRR的F-box蛋白以及其他具有未知C末端基序的F-box蛋白相互作用良好。我们还观察到F-box蛋白与ASK3、ASK9、ASK13、ASK14、ASK16和ASK18之间存在特异性相互作用。相比之下，我们未检测到12种ASK蛋白中的任何一种与含有CRFA、CRFB或CRFC结构域的F-box蛋白之间存在相互作用。对8个ASK基因表达的组织化学和RT-PCR分析均揭示了各个基因独特的表达模式。
