The sugars-will-eventually-be-exported-transporters (SWEET) family is a newly characterized group of sugar transporters, which plays an important role in diverse biological processes, including plant growth, development, and response to abiotic and biotic stresses. SWEET family genes, known as SWEETs , have been characterized in many plant species, but a comprehensive analysis has not been performed on citrus. Here, 27 citrus SWEET genes ( CitSWEETs ) were identified through homology searches. The phylogenetic relationship, transmembrane helices (TMHs), gene distribution, and gene structure were then investigated. Furthermore, the expression patterns of 27 CitSWEET s were examined in several tissues and under different abiotic stresses. The data revealed that CitSWEET1 , CitSWEET2 , CitSWEET3 , CitSWEET4 , CitSWEET7 , CitSWEET25 , and CitSWEET27 were tissue-specific, and others were ubiquitously expressed. Among 27 genes tested, some members were sensitive to abiotic stress or hormone stimuli, and CitSWEET3 transported glucose in EMY4000 yeast strain. In conclusion, we performed the first comprehensive analysis of the CitSWEET gene family in citrus, which can provide useful information to further analyze their potential roles.

中文翻译：

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瓦伦西亚甜橙 SWEET 基因家族的全基因组鉴定及其对非生物胁迫的响应

糖最终出口转运蛋白 (SWEET) 家族是一组新表征的糖转运蛋白，它在多种生物过程中发挥重要作用，包括植物生长、发育以及对非生物和生物胁迫的反应。SWEET 家族基因，称为 SWEETs，已在许多植物物种中得到表征，但尚未对柑橘进行综合分析。在这里，通过同源性搜索鉴定了 27 个柑橘 SWEET 基因 (CitSWEETs)。然后研究了系统发育关系、跨膜螺旋（TMHs）、基因分布和基因结构。此外，在几种组织和不同的非生物胁迫下检查了 27 个 CitSWEET 的表达模式。数据显示，CitSWEET1、CitSWEET2、CitSWEET3、CitSWEET4、CitSWEET7、CitSWEET25、和 CitSWEET27 是组织特异性的，其他的则普遍表达。在测试的 27 个基因中，一些成员对非生物胁迫或激素刺激敏感，CitSWEET3 在 EMY4000 酵母菌株中转运葡萄糖。总之，我们对柑橘中的 CitSWEET 基因家族进行了首次综合分析，可以为进一步分析其潜在作用提供有用的信息。