Abstract Aberrant pollen development gene 2 (APD2) encodes a plant-specific RING-finger ubiquitin-protein, which may play an important role in pollen development or fruit development and ripening. However, the role of ubiquitin-proteins in fruit quality formation is not clear. In this study, we successfully cloned an Arabidopsis APD2 homologous gene (CsAPD2) from the citrus genome. The full-length sequence of CsAPD2 has 1431 nucleotides, encoding a protein of 476 amino acids. This gene contains ten exons and nine introns with two transmembrane domains and one RING-finger domain. The tissue-specific transcript analysis showed that CsAPD2 was predominantly expressed in fruit juice sacs (JS), followed by young leaves. Moreover, temporal expression analysis in the JS of six citrus cultivars displayed a significantly positive correlation coefficient (0.939, P

中文翻译：

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CsAPD2的鉴定和转录分析揭示其在柑橘类水果柠檬酸积累中的潜在作用

摘要 异常花粉发育基因2 (APD2) 编码植物特异性环指泛素蛋白，可能在花粉发育或果实发育成熟中起重要作用。然而，泛素蛋白在果实品质形成中的作用尚不清楚。在这项研究中，我们成功地从柑橘基因组中克隆了一个拟南芥 APD2 同源基因 (CsAPD2)。CsAPD2的全长序列有1431个核苷酸，编码476个氨基酸的蛋白质。该基因包含十个外显子和九个内含子，具有两个跨膜结构域和一个环指结构域。组织特异性转录分析表明 CsAPD2 主要在果汁囊 (JS) 中表达，其次是幼叶。此外，六个柑橘品种的 JS 中的时间表达分析显示出显着的正相关系数 (0.