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PAP2 (Production of anthocyanin segment 2) encodes MYB transcription factor, and regulates anthocyanin synthesis by forming MYB-bHLH-WD40 complex with bHLH and WD40. In this study we cloned PAP2 gene in Brassica, and preliminarily verified the function of PAP2, providing a reference for further understanding the regulatory mechanism of anthocyanin synthesis in Brassica. Two and one copies of PAP2 gene were cloned from Brassica carinata and Brassica nigra, respectively, and named as BcaB.PAP2, BcaC.PAP2, BniB.PAP2. These three genes are composed of 3 exons and 2 introns, encoding 247 amino acids. Based on the PAP2 gene sequences cloned in this study and other reported PAP2 gene sequences of Brassica, three pairs of primers were designed to detect the PAP2 gene of A, B and C genomes respectively, and the genomic origin of PAP2 of six species in the U's Triangle of Brassica could be distinguished by allele specific PCR. The BjuB.PAP2 gene from the B genome of Brassica juncea was selected to construct an overexpression vector and transformed into Arabidopsis thaliana. The transgenic Arabidopsis leaves turned purple, indicating that PAP2 gene is regulating anthocyanin synthesis. After shading treatment for 10 days, the purple color of Brassica carinata lightened, and the anthocyanin content decreased by 41.22%. Quantitative PCR and transcriptomic studies showed that the expression of BcaB.PAP2 and BcaC.PAP2 in the leaves of shading plants decreased. The expression of structural genes for anthocyanin synthesis, such as chalcone synthase gene (CHS), chalcone isomerase gene (CHI), flavanone 3-hydroxylase gene (F3H), dihydroflavonol reductase gene (DFR), anthocyanin synthase gene (ANS), flavonoid 3-glucosyltransferase gene (UFGT) and other genes were also decreased. This study completed the cloning of PAP2 gene of Brassica carinata and Brassica nigra, and carried out their evolutionary analysis. Allele specific PCR primers were designed according to the sequences of PAP2 gene cloned in this experiment and other reported genes to provide molecular markers for the genomic transmission identification of PAP2 gene in Brassica interspecific hybrids. Through the transformation of BjuB.PAP2 gene into Arabidopsis plants, it was found that PAP2 gene was involved in the accumulation of anthocyanins. It was found that the expression of BcaPAP2 gene and anthocyanin synthesis structure gene were induced by light after shading. This study cloned the PAP2 gene in Brassica and preliminarily verified its function, providing a reference for further understanding the regulatory mechanism of anthocyanin synthesis in Brassica plants. [ABSTRACT FROM AUTHOR]

Rapeseed (Brassica napus L.) silique is easy to crack in late maturity. To better understand the mechanism of shatter resistance, and to identify the resistanct germplasm, BnFUL gene family memmbers were studied by bioinformatics analysis. Five BnFUL genes were identified from rapeseed cv Zhongshuang 11 (ZS11), which are located on chromosomes A02, A03, C02, C07 and C09. Their physical and chemical properties of the encoded proteins were similiar. Protein secondary structure was mainly consisting with α-helix. Gene structure showed that all BnFUL genes contained 8 exons- and all 5 members had one MADS_MEF2_like domain and one K-box domain. Motif analysis showed that family members all contained 7 motifs. The family was conserved during evolution from the 5 memmbers' evolutionary tree and collinearity analysis. Gene expression analysis showed that the BnFULs were highly expressed in stems- leaves and fruits. [ABSTRACT FROM AUTHOR]

In order to reveal the effects of Cd stress on the growth of B. napus seedlings, phenotype, physiological responses, and gene expression of B. napus under different concentration of Cd treatment were investigated through pot experiment. Our results showed that B. napus seedlings had a certain degree of tolerance to low concentration of Cd treatment since no significant difference in phenotype was observed between plants under 5 mg/kg and control. However, higher concentration of Cd treatment (30 and 50 mg/kg) could suppress the growth of B. napus seedlings, as the plant height, fresh weight, leaf area and chlorophyll content of B. nupus under higher concentration of Cd decreased significantly as compared with control, while soluble protein content and activities of two antioxidant enzymes (SOD and POD) increased significantly. The Cd content in both roots and leaves of oilseed rape increased sharply with the increased of Cd concentration. Meanwhile, Cd treatment also affected the accumulation of other metals in plants, such as Mn, Mg, Zn and Cu. Comparative transcriptome analysis of B. napus under different concentration of Cd treatments found that these differentially expressed genes were mainly concentrated in the anti-oxidant activity, photosystem, ATPase activity, cell wall organization or biogenesis and so on. Analysis of the expression patterns of HMA gene family showed that HMA3 was up-regulated, HMA2 and HMA4 were down regulated in roots of B. napus under Cd treatments when compared with control. These differentially expressed genes might have contributed to Cd tolerance of B. napus. [ABSTRACT FROM AUTHOR]