Research Of Artemisnin Synthesis Related Genes Influence By Low Temperature And Circadian Rhythm

Artemisia annua L. medicinal value has been widespread concerned, but the functions of artemisinin product related genes are yet to be worked out. Circadian changes caused by the earth’s rotation are one of environments that the plants have to face, and the most of the internal rhythms of plants are associated with some rhythm genes. Light, temperature or other environmental factors can retune the plants circadian rhythm, and rhythm phase changes. The target of this study was to analyze differential genes expression associated with artemisinin content in planta influenced by low temperature or circadian rhythm.Artemisinin had been found in leaves, flowers, but not in roots. The changes of leaves artemisinin in Artemisia annua L. showed circadian rhythmic expression patterns, with one peak at14o’clock and one trough at8o’clock.Twenty artemisinin related genes and four circadian genes were analyzed by real-time quantitative PCR. The ADS, CYP71AV1, ALDH1genes had the same daily quantity variety as artemisinin content, with peaks at14o’clock and troughs at8o’clock. ECS, SQS genes in leaves had peaks at8o’clock, and the troughs at14o’clock, which showed the opposite variation trend of artemisinin. Artemisinin related genes did not spend significant regular changes in the flower.Low temperature increased artemisinin synthesis, but did not show circadian rhythm. The ALDH1gene expression was down overall compared with room temperature control, its expression pattern was consistent with control, and did not affected by low temperatures. ADS and. CYP71AV1genes had the same expression patterns as artemisinin content.In this study, rotary evaporation and vacuum methods were employed to compare artemisinin extraction. Recoveries, precision, stability and repeatability showed that the two methods were insignificant. However, the steps of vacuum extraction method were easier for multiple samples.Together these data showed that leaves artimisinin content had circadian rhythm; artimisinin related genes ADS, CYP71AV1, ALDH1were also circadian genes; ADS, CYP71AV1were regulated by low temperature, but not for ALDH1gene.