遮光对长春花叶片长春碱含量和相关合成基因表达的影响

Effects of Shading Light on Alkaloids and Related Genes Expression in Leaves of Catharanthus roseus

分别在红色滤光膜遮光处理和正常日光灯照条件下,研究长春花(Catharanthus roseus)无菌幼苗叶片中叶绿素含量和生物碱含量以及生物碱合成相关基因的表达变化。结果表明:与对照相比,叶片中叶绿素含量在前30d先升高,然后明显降低(P<0.05),叶绿素a/b比率低于对照;文多灵(vindoline,VIN)和长春质碱(catharanthine,CAT)的含量稍高于对照后下降,VIN和CAT耦合的重要抗癌产物长春碱(vinblastine,VBL)的含量逐渐高于对照,在处理第15天达到最高为(0.0280±0.0051)mg/g;遮光处理有利于VBL合成路径相关基因(Tdc、Str、Dat和D4h)的表达,表明植物在适应遮光胁迫过程中发挥着积极的调控作用。

Effects of red plastic films and fluorescent light（as control）on the contents of chlorophyll,alkaloids and the expression of biosynthesis pathway genes in the leaves of Catharanthus roseus aseptic seedlings were studied.The results showed that chlorophyll content in leaves was higher under red films than that under fluorescent light on the first 30 d,and the chlorophyll content under red films decreased significantly after 3 d（P〈0.05）.The ratio of chlorophyll a/b was lower than control.The content of vindoline（VIN）and catharanthine（CAT）firstly increased a little and then decreased compared with control.The content of vinblastine（VBL）,as a coupling product of VIN and CAT increased gradually and reached the highest on the 15th day（0.028 0±0.005 1）mg/g in shade culture.The plastic films induced the high expression of alkaloids biosynthesis pathway genes（Tdc,Str,Dat and D4h）.The results indicated that plants under shade treatment with red films were positively regulated by physiological metabolisms.