Originating in the subtropics, cucumbers require warm weather and plenty of light, low light inhibits the growth of cucumbers. For cucumbers to efficiently absorb light energy in low light, chlorophyll synthesis is necessary. Oxygenase for chlorophyllate is encoded by . RNA interference (RNAi) was used to reduce expression in cucumber, reduced chlorophyll content and Fv/Fm (maximal photochemical efficiency of photosystem II) were found in RNAi- lines. The Arabidopsis mutant lacks chlorophyll and has a low Fv/Fm, but overexpressing restored the mutant's phenotype. gene expression was found to be upregulated in the presence of low light. The Y1H screening assay revealed that CsHsfA6b and CsBLH4 were potential expression regulators. The results of the Y1H, LUC/REN, and EMSA assays confirmed that only CsBLH4 can bind to the promoter. Furthermore, like , the mutant had low chlorophyll content and Fv/Fm. overexpression in the mutant increased the content of chlorophyll and Fv/Fm, especially under low light conditions. CsBLH4 targeting was found to positively regulate chlorophyll synthesis and photosynthetic capacity in cucumber under low light conditions in our study.

中文翻译：

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CsBLH4 靶向 CsCAO 调节弱光胁迫下的叶绿素合成代谢

黄瓜原产于亚热带，需要温暖的气候和充足的光照，弱光会抑制黄瓜的生长。为了使黄瓜在弱光下有效吸收光能，叶绿素的合成是必要的。叶绿素加氧酶由 编码。 RNA 干扰 (RNAi) 用于减少黄瓜中的表达，在 RNAi 系中发现叶绿素含量和 Fv/Fm（光系统 II 的最大光化学效率）降低。拟南芥突变体缺乏叶绿素且 Fv/Fm 较低，但过表达恢复了突变体的表型。发现在弱光存在下基因表达上调。 Y1H 筛选分析显示 CsHsfA6b 和 CsBLH4 是潜在的表达调节因子。 Y1H、LUC/REN 和 EMSA 测定的结果证实，只有 CsBLH4 可以与启动子结合。此外，与 一样，突变体的叶绿素含量和 Fv/Fm 也较低。突变体中的过度表达增加了叶绿素和 Fv/Fm 的含量，特别是在弱光条件下。我们的研究发现，CsBLH4 靶向可以在弱光条件下积极调节黄瓜的叶绿素合成和光合能力。