Cotton that serves natural fiber for the textile industry is an important industrial crop. However, abiotic stress imposed a significant negative impact on yield and quality of cotton fiber. Carotenoid cleavage oxygenases (CCOs) that specifically catalyze the cleavage of carotenoid are essential for plant growth and development and abiotic stress response. While information of cotton CCOs and their potential functions in abiotic stress is still far from satisfactory, which imposes restrictions on application in genetic breeding for stress resistance. In this study, 15, 15, and 30 CCOs were identified from Gossypium arboreum, Gossypium raimondii, and Gossypium hirsutum, respectively. Phylogenetic relationship indicated that CCO genes could be classified into two groups (NCEDs and CCDs). Cis-elements prediction showed that there were 18 types of stress-related cis-elements in promoter regions. Analysis with transcriptome data revealed tissue-specific expression pattern of cotton CCOs. qRT-PCR analysis revealed only that GhNCED3a_A/D and GhNCED3c_A/D had strong response to drought, salt, and cold stress, while GhCCD1_A/D and GhCCD4_A showed relatively slight expression changes. Virus-induced gene silencing of GaNCED3a, the ortholog gene of GhNCED3a_A/D, suggested that silenced plants exhibited decreased resistance not only to drought but also to salt, with significantly reduced proline content, and high malondialdehyde content and water loss rate. In addition, stress response genes RD29A, DREB1A, and SOS1 significantly downregulated under drought and salt stress in silenced plants compared to control plants, indicating that GaNCED3a played an important role in drought and salt response. The results provided valuable insights into function analysis of cotton CCOs in abiotic stress response, and suggested potential benefit genes for stress-resistant breeding.

为纺织业提供天然纤维的棉花是重要的工业作物。然而，非生物胁迫对棉花纤维的产量和质量产生了显着的负面影响。特异性催化类胡萝卜素裂解的类胡萝卜素裂解加氧酶 (CCO) 对于植物生长发育和非生物胁迫响应至关重要。而棉花CCOs及其在非生物胁迫中的潜在功能的信息仍远未令人满意，这限制了其在抗逆遗传育种中的应用。在这项研究中，15，15，30 ，CCOS从确定树棉，棉雷蒙德氏棉和陆地棉， 分别。系统发育关系表明CCO基因可分为两类（NCEDs和CCDs）。顺式元件预测结果表明启动子区有18种与胁迫相关的顺式元件。对转录组数据的分析揭示了棉花CCO 的组织特异性表达模式。qRT-PCR 分析仅显示GhNCED3a_A/D和GhNCED3c_A/D对干旱、盐分和冷胁迫有较强的响应，而GhCCD1_A/D和GhCCD4_A 的表达变化相对较小。病毒诱导的GaNCED3a基因沉默GhNCED3a_A/D的直系同源基因，表明沉默的植物不仅对干旱而且对盐的抗性都表现出降低，脯氨酸含量显着降低，丙二醛含量和失水率高。此外，与对照植物相比，在干旱和盐胁迫下，沉默植物的胁迫响应基因RD29A、DREB1A和SOS1显着下调，表明GaNCED3a在干旱和盐分响应中起重要作用。该结果为棉花CCOs在非生物胁迫响应中的功能分析提供了有价值的见解，并为抗逆育种提出了潜在的有益基因。