Joseph Mary Prathiba, Papdi Csaba, Kozma-Bognár László, Nagy István, López-Carbonell Marta, Rigó Gábor, Koncz Csaba, Szabados László
Institute of Plant Biology, Biological Research Centre, H-6726 Szeged, Hungary (M.P.J., C.P., L.K.-B., I.N., G.R., C.K., L.S.);Department of Plant Biology, University of Barcelona, 08028 Barcelona, Spain (M.L.-C.);Max-Planck-Institut für Züchtungsforschung, 50829 Cologne, Germany (C.K.); andRoyal Holloway, University of London, Surrey TW20 0EX, United Kingdom (C.P.).
Institute of Plant Biology, Biological Research Centre, H-6726 Szeged, Hungary (M.P.J., C.P., L.K.-B., I.N., G.R., C.K., L.S.);Department of Plant Biology, University of Barcelona, 08028 Barcelona, Spain (M.L.-C.);Max-Planck-Institut für Züchtungsforschung, 50829 Cologne, Germany (C.K.); andRoyal Holloway, University of London, Surrey TW20 0EX, United Kingdom (C.P.)
Plant Physiol. 2014 Jul;165(3):1203-1220. doi: 10.1104/pp.113.234294. Epub 2014 May 7.
Seed germination is controlled by environmental signals, including light and endogenous phytohormones. Abscisic acid (ABA) inhibits, whereas gibberellin promotes, germination and early seedling development, respectively. Here, we report that ZFP3, a nuclear C2H2 zinc finger protein, acts as a negative regulator of ABA suppression of seed germination in Arabidopsis (Arabidopsis thaliana). Accordingly, regulated overexpression of ZFP3 and the closely related ZFP1, ZFP4, ZFP6, and ZFP7 zinc finger factors confers ABA insensitivity to seed germination, while the zfp3 zfp4 double mutant displays enhanced ABA susceptibility. Reduced expression of several ABA-induced genes, such as RESPONSIVE TO ABSCISIC ACID18 and transcription factor ABSCISIC ACID-INSENSITIVE4 (ABI4), in ZFP3 overexpression seedlings suggests that ZFP3 negatively regulates ABA signaling. Analysis of ZFP3 overexpression plants revealed multiple phenotypic alterations, such as semidwarf growth habit, defects in fertility, and enhanced sensitivity of hypocotyl elongation to red but not to far-red or blue light. Analysis of genetic interactions with phytochrome and abi mutants indicates that ZFP3 enhances red light signaling by photoreceptors other than phytochrome A and additively increases ABA insensitivity conferred by the abi2, abi4, and abi5 mutations. These data support the conclusion that ZFP3 and the related ZFP subfamily of zinc finger factors regulate light and ABA responses during germination and early seedling development.
种子萌发受环境信号控制，包括光和内源植物激素。脱落酸（ABA）抑制种子萌发，而赤霉素促进种子萌发和早期幼苗发育。在此，我们报道ZFP3，一种核C2H2锌指蛋白，在拟南芥中作为ABA抑制种子萌发的负调控因子。相应地，ZFP3以及与之密切相关的ZFP1、ZFP4、ZFP6和ZFP7锌指因子的调控过表达赋予种子萌发对ABA不敏感，而zfp3 zfp4双突变体对ABA的敏感性增强。在ZFP3过表达幼苗中，几个ABA诱导基因，如对脱落酸响应18和转录因子脱落酸不敏感4（ABI4）的表达降低，表明ZFP3负调控ABA信号传导。对ZFP3过表达植株的分析揭示了多种表型改变，如半矮化生长习性、育性缺陷以及下胚轴伸长对红光而非远红光或蓝光的敏感性增强。与光敏色素和abi突变体的遗传互作分析表明，ZFP3通过除光敏色素A之外的光受体增强红光信号传导，并累加增加abi2、abi4和abi5突变赋予的对ABA不敏感。这些数据支持以下结论：ZFP3以及锌指因子的相关ZFP亚家族在种子萌发和早期幼苗发育过程中调控光和ABA反应。
