β-胡萝卜素羟化酶(β-carotene hydroxylase,chyb)作为盐生杜氏藻(Dunaliella viridis)胡萝卜素合成代谢途径中的关键酶,催化β-胡萝卜素经两步反应合成玉米黄素。盐生杜氏藻chyb基因在植物抗逆性方面有重要研究价值。本研究利用前期克隆得到的盐生杜氏藻chyb基因(Gen Bank登录号:JN118489),构建了植物表达载体p CAMBIA3301-chyb。通过根癌农杆菌(Agrobacterium tumefaciens)LBA4404介导的叶盘法将其转入烟草(Nicotiana tabacum),获得16株草铵膦抗性再生植株,经PCR及RT-PCR扩增分析表明,chyb基因已转入其中13株烟草植株中,并可以进行正常转录。通过测定转基因烟草的株高、叶面积、叶绿素含量、叶片相对电导率和脯氨酸含量对转基因烟草的耐盐性进行了检测,结果表明,与对照组相比,转基因烟草的株高、叶面积、叶绿素含量均极显著提高(P<0.01),其中转基因烟草平均株高为37.82cm,是对照组烟草平均株高的1.37倍。在100 mmol/L Na Cl胁迫处理下,转基因烟草的成活率为84.45%,是对照组烟草的1.58倍;在200 mmol/L Na Cl胁迫下对照组烟草萎蔫死亡,而转基因烟草仍可生长存活。经检测转基因烟草叶片的相对电导率升高但变化幅度较小,脯氨酸含量较对照组极显著增加(P<0.01)。研究结果说明转基因烟草的耐盐性得到了提高,为进一步探讨盐生杜氏藻chyb基因在植物耐盐性方面的功能提供基础资料。 β-carotene hydroxylase (chyb), as a key enzyme in the metabolic pathway of carotenoids from Dunaliella viridis, catalyzes the synthesis of zeaxanthin by two steps reaction of β-carotene. The chyb gene of Dunaliella salina has important research value in plant stress resistance. In this study, we constructed the plant expression vector p CAMBIA3301-chyb by using chyb gene of chondrus salivarius Chyb from GenBank (GenBank accession number: JN118489). Sixteen glufosinate-resistant plants were obtained by Agrobacterium tumefaciens LBA4404-mediated leaf disc method. Nicotiana tabacum was transformed into tobacco plants by PCR and RT-PCR. The chyb gene It has been transferred to 13 of these tobacco plants and can be normally transcribed. The transgenic tobacco plants were tested for salt tolerance by measuring plant height, leaf area, chlorophyll content, leaf relative conductivity and proline content. The results showed that compared with the control group, plant height, Area and chlorophyll content increased significantly (P <0.01). The mean height of transgenic tobacco was 37.82 cm, which was 1.37 times of the average tobacco plant height in control group. Under 100 mmol / L NaCl stress, the survival rate of transgenic tobacco was 84.45%, which was 1.58 times that of the control tobacco. Under the stress of 200 mmol / L NaCl, the control group tobacco wilted, while the transgenic tobacco could still survive and survive . Compared with the control group, the relative electrical conductivity of the tested transgenic tobacco leaves increased but the change range was small, and the content of proline significantly increased (P <0.01). The results showed that the salt tolerance of transgenic tobacco was enhanced, which provided basic information for further exploring the function of chyb gene of Dunaliella salina in the salt tolerance of plants.