tailieunhanh - báo cáo khoa học: " A cytochrome P450 monooxygenase commonly used for negative selection in transgenic plants causes growth anomalies by disrupting brassinosteroid signaling"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: A cytochrome P450 monooxygenase commonly used for negative selection in transgenic plants causes growth anomalies by disrupting brassinosteroid signaling | A cytochrome P450 monooxygenase commonly used for negative selection in transgenic plants causes growth anomalies by disrupting brassinosteroid signaling Dasgupta et al. Dasgupta et al. BMC Plant Biology 2011 11 67 http 1471-2229 11 67 15 April 2011 BioMed Central Dasgupta et al. BMC Plant Biology 2011 11 67 http 1471-2229 11 67 BMC Plant Biology RESEARCH ARTICLE Open Access A cytochrome P450 monooxygenase commonly used for negative selection in transgenic plants causes growth anomalies by disrupting brassinosteroid signaling Kasturi Dasgupta1 Savita Ganesan2 Sindhu Manivasagam1 and Brian G Ayre1 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