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National ideologies have become less powerful because governments have been unable to deliver conditions favorable to social and economic well being. When the power of ideology is weakened it leaves a vacuum which is filled by a move toward ethnic conflict. The increased importance of ethnicity further erodes the power of ideology. Conversely, the strengthening of ideology can weaken the significance given to ethnicity. Belief in a set of ideals can erode the divisive power of ethnicity.

Abstract Background Cytochrome P450 monooxygenases form a large superfamily of enzymes that catalyze diverse reactions. The P450SU1 gene from the soil bacteria Streptomyces griseolus encodes CYP105A1 which acts on various substrates including sulfonylurea herbicides, vitamin D, coumarins, and based on the work presented here, brassinosteroids. P450SU1 is used as a negative-selection marker in plants because CYP105A1 converts the relatively benign sulfonyl urea pro-herbicide R7402 into a highly phytotoxic product. Consistent with its use for negative selection, transgenic Arabidopsis plants were generated with P450SU1 situated between recognition sequences for FLP recombinase from yeast to select for recombinase-mediated excision. However, unexpected and prominent developmental aberrations resembling those described for mutants defective in brassinosteroid signaling were observed in many of the lines. Results The phenotypes of the most affected lines included severe stunting, leaf curling, darkened leaves characteristic of anthocyanin accumulation, delayed transition to flowering, low pollen and seed yields, and delayed senescence. Phenotype severity correlated with P450SU1 transcript abundance, but not with transcript abundance of other experimental genes, strongly implicating CYP105A1 as responsible for the defects. Germination and seedling growth of transgenic and control lines in the presence and absence of 24-epibrassinolide indicated that CYP105A1 disrupts brassinosteroid signaling, most likely by inactivating brassinosteroids. Conclusions Despite prior use of this gene as a genetic tool, deleterious growth in the absence of R7402 has not been elaborated. We show that this gene can cause aberrant growth by disrupting brassinosteroid signaling and affecting homeostasis.

The level of anthocyanins in plants vary widely among cultivars, developmental stages and environmental stimuli. Previous studies have reported that the expression of various MYBs regulate anthocyanin pigmentation during growth and development. Here we examine the activity of 3 novel R2R3-MYB transcription factor (TF) genes,PamMybA.1, PamMybA.3andPamMybA.5fromPrunus americana. The anthocyanin accumulation patterns mediated byCaMV double35Spromoter (db35Sp) controlled expression of the TFs in transgenic tobacco were compared with citrus-MoroMybA, Arabidopsis-AtMybA1and grapevine-VvMybA1transgenics during their entire growth cycles. Thedb35Sp-PamMybA.1anddb35Sp-PamMybA.5 constructs induced high levels of anthocyanin accumulation in both transformed tobacco calli and the regenerated plants. The red/purple color pigmentation induced in thePamMybA.1andPamMybA.5 lines was not uniformly distributed, but appeared as patches in the leaves, whereas the flowers showed intense uniform pigmentation similar to theVvMybA1expressing lines.MoroMybAandAtMybA1showed more uniform pink coloration in both vegetative and reproductive tissues. Plant morphology, anthocyanin content, seed viability, and transgene inheritance were examined for thePamMybA.5transgenic plants and compared with the controls. We conclude that these TFs alone are sufficient for activating anthocyanin production in plants and may be used as visible reporter genes for plant transformation. Evaluating these TFs in a heterologous crop species such as citrus further validated that these genes can be useful for the metabolic engineering of anthocyanin production and cultivar enhancement. [ABSTRACT FROM AUTHOR]