Chen Pei, Sun Yu-Fei, Kai Wen-Bin, Liang Bin, Zhang Yu-Shu, Zhai Xia-Wan, Jiang Li, Du Yang-Wei, Leng Ping
College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, PR China.
College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, PR China.
J Plant Physiol. 2016 Oct 20;205:67-74. doi: 10.1016/j.jplph.2016.07.016. Epub 2016 Aug 27.
Abscisic acid (ABA) regulates fruit development and ripening via its signaling. However, the exact role of ABA signaling core components in fruit have not yet been clarified. In this study, we investigated the potential interactions of tomato (Solanum lycopersicon) ABA signaling core components using yeast two-hybrid analysis, with or without ABA at different concentrations. The results showed that among 12 PYR/PYL/RCAR ABA receptors (SlPYLs), SlPYL1, SlPYL2, SlPYL4, SlPYL5, SlPYL 7, SlPYL8, SlPYL9, SlPYL10, SlPYL11, and SlPYL13 were ABA-dependent receptors, while SlPYL3 and SlPYL12 were ABA-independent receptors. Among five SlPP2Cs (type 2C protein phosphatases) and seven SlSnRK2s (subfamily 2 of SNF1-related kinases), all SlSnRK2s could interact with SlPP2C2, while SlSnRK2.8 also interacted with SlPP2C3. SlSnRK2.5 could interact with SlABF2/4 (ABA-responsive element binding factors). Expressions of SlPYL1, SlPYL2, SlPYL8, and SlPYL10 were upregulated under exogenous ABA but downregulated under nordihydroguaiaretic acid (NDGA) at the mature green stage of fruit ripening. The expressions of SlPP2C1, SlPP2C2, SlPP2C3, and SlPP2C5 were upregulated in ABA-treated fruit, but downregulated in NDGA-treated fruit at the mature green stage. The expressions of SlSnRK2.4, SlSnRK2.5, SlSnRK2.6, and SlSnRK2.7 were upregulated by ABA, but downregulated by NDGA. However, SlSnRK2.2 was down regulated by ABA. Expression of SlABF2/3/4 was enhanced by ABA but decreased by NDGA. Based on these results, we concluded that the majority of ABA receptor PYLs interact with SlPP2Cs in an ABA-dependent manner. SlPP2C2 and SlPP2C3 can interact with SlSnRK2s. SlSnRK2.5 could interact with SlABF2/4. Most ABA signaling core components respond to exogenous ABA.
脱落酸（ABA）通过其信号传导调控果实发育和成熟。然而，ABA信号传导核心组分在果实中的具体作用尚未明确。在本研究中，我们利用酵母双杂交分析，研究了番茄（Solanum lycopersicon）ABA信号传导核心组分在不同浓度ABA存在或不存在的情况下的潜在相互作用。结果表明，在12个PYR/PYL/RCAR ABA受体（SlPYLs）中，SlPYL1、SlPYL2、SlPYL4、SlPYL5、SlPYL7、SlPYL8、SlPYL9、SlPYL10、SlPYL11和SlPYL13是依赖ABA的受体，而SlPYL3和SlPYL12是不依赖ABA的受体。在5个SlPP2C（2C型蛋白磷酸酶）和7个SlSnRK2（SNF1相关激酶亚家族2）中，所有SlSnRK2都能与SlPP2C2相互作用，而SlSnRK2.8也能与SlPP2C3相互作用。SlSnRK2.5能与SlABF2/4（ABA反应元件结合因子）相互作用。在果实成熟绿熟期，外源ABA处理下SlPYL1、SlPYL2、SlPYL8和SlPYL10的表达上调，而在去甲二氢愈创木酸（NDGA）处理下表达下调。在成熟绿熟期，ABA处理的果实中SlPP2C-1、SlPP2C2、SlPP2C3和SlPP2C5的表达上调，而NDGA处理的果实中表达下调。SlSnRK2.4、SlSnRK2.5、SlSnRK2.6和SlSnRK2.7的表达受ABA上调，但受NDGA下调。然而，SlSnRK2.2受ABA下调。SlABF2/3/4的表达受ABA增强，但受NDGA降低。基于这些结果，我们得出结论，大多数ABA受体PYLs以依赖ABA的方式与SlPP2Cs相互作用。SlPP2C2和SlPP2C3能与SlSnRK2s相互作用。SlSnRK2.5能与SlABF2/4相互作用。大多数ABA信号传导核心组分对外源ABA有反应。
