Project description:Evolutionary responses to polyploidization driving species diversification and local environmental adaptation in Orychophragmus (PRJCA035915)
Project description:Oilseed rape is both an important oleaginous crop and agriculture sightseeing crop whereas has relatively scanty flower color. As natural flavonoids, Anthocyanin are responsible for the attractive red, purple, and blue colors of various tissues in higher plants, especially for the ornamental plants flower. One Brassica napus-Orychophragmus violaceus disomic addition line (M4) obtained previously exhibits red petals whichresult from anthocyanin biosynthesis. Transcriptome analysis of M4, B. napus (H3), natural individuals of O. violaceus with purple petals (OvP) and white petals (OvW) revealed that most of structural genes for the anthocyanin synthesis were up-regulated in both M4 and OvP, especially key gene ANS in the last step. Reads assembling and sequence alignment showed that the regulatory DEG PAP2 in M4 was from the transcript of O. violaceus. OvPAP2 was transformed into Arabidopsis thaliana and B. napus driven by the CaMV35S promoter and the rape petal-specific prompter XY355. Transgenic A. thaliana plants showed different levels of purple pigments in most of the organs, including the petals, and transgenic B. napus flowers exhibited restricted accumulation of anthocyanins in stamens when driven by CaMV35S promoter, but generated both red petals and anthers driven by the XY355 promoter. These results provided a platform for expounding the anthocyanin biosynthesis pathway in B. napus petals and give a successful case for flower color modification of the agriculture sightseeing rape.
Project description:Oilseed rape (Brassica napus L.), which has yellow flowers, is both an important oil crop and a traditional tourism resource in China, whereas the Orychophragmus violaceus, which has purple flowers, likely possesses a candidate gene or genes to alter the flower colour of oilseed rape. A previously established B. napus line has a particular pair of O. violaceus chromosomes (M4) and exhibits slightly red petals. In this study, the transcriptomic analysis of M4, B. napus (H3), and O. violaceus with purple petals (OvP) and with white petals (OvW) revealed that most anthocyanin biosynthesis genes were up-regulated in both M4 and OvP. Read assembly and sequence alignment identified a homolog of AtPAP2 in M4, which produced the O. violaceus transcript (OvPAP2). The overexpression of OvPAP2 via the CaMV35S promoter in Arabidopsis thaliana led to different levels of anthocyanin accumulation in most organs, including the petals. However, the B. napus overexpression plants showed anthocyanin accumulation primarily in the anthers, but not the petals. However, when OvPAP2 was driven by the petal-specific promoter XY355, the transgenic B. napus plants produced red anthers and red petals. The results of metabolomic experiments showed that specific anthocyanins accumulated to high levels in the red petals. This study illustrates the feasibility of producing red-flowered oilseed rape, thereby enhancing its ornamental value, via the ectopic expression of the OvPAP2 gene. Moreover, the practical application of this study for insect pest management in the crop is discussed.
Project description:Production of Red Flower Rapeseed by Ectopic Expression of OvPAP2 Identified in Brassica napus-Orychophragmus violaceus Addition Line by Comparative Transcriptome Analysis
