Abstract:
VQ1 and VQ10 are largely unstructured homologous proteins with a significant potential for protein-protein interactions. Yeast two-hybrid (Y2H) analysis confirmed that both proteins interact not only with themselves and each other but also with other VQ and WRKY proteins. Screening an Arabidopsis Y2H library with VQ1 as bait identified 287 interacting proteins. Validation of the screening confirmed that interactions with VQ1 also occurred with VQ10, supporting their functional homology. Although VQ1 or VQ10 proteins do not localize in plastids, 47 VQ1-targets were found to be plastidial proteins. In planta interaction with the isoprenoid biosynthetic enzyme 1-deoxy-D-xylulose-5-phosphate synthase (DXS) was confirmed by co-immunoprecipitation. DXS oligomerizes through redox-regulated intermolecular disulfide bond formation, and the interaction with VQ1 or VQ10 do not involve their unique C residues. The VQ-DXS protein interaction did not alter plastid DXS localization or its oligomerization state. Although plants with enhanced or reduced VQ1 and VQ10 expression did not exhibit significantly altered levels of isoprenoids compared to wild-type plants, they did display significantly improved or diminished photosynthesis efficiency, respectively.
摘要:
VQ1和VQ10主要是非结构化的同源蛋白,具有蛋白质-蛋白质相互作用的重要潜力。酵母双杂交(Y2H)分析证实,两种蛋白质不仅与自身相互作用,而且与其他VQ和WRKY蛋白质相互作用。以VQ1为诱饵筛选拟南芥Y2H文库,鉴定出287种相互作用蛋白。筛选的验证证实与VQl的相互作用也与VQ10发生,支持它们的功能同源性。虽然VQ1或VQ10蛋白不定位在质体中,发现47个VQ1靶标是质体蛋白。在植物中,通过共免疫沉淀证实了与类异戊二烯生物合成酶1-脱氧-D-木酮糖-5-磷酸合酶(DXS)的相互作用。DXS通过氧化还原调节的分子间二硫键形成寡聚化,与VQ1或VQ10的相互作用不涉及它们独特的C残基。VQ-DXS蛋白相互作用不改变质体DXS定位或其寡聚化状态。尽管与野生型植物相比,VQ1和VQ10表达增强或降低的植物没有表现出类异戊二烯水平的显著改变,它们确实显示出显著提高或降低的光合作用效率,分别。