tailieunhanh - báo cáo khoa học: " Genetic and transformation studies reveal negative regulation of ERS1 ethylene receptor signaling in Arabidopsis"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Genetic and transformation studies reveal negative regulation of ERS1 ethylene receptor signaling in Arabidopsis | Liu et al. BMC Plant Biology 2010 10 60 http 1471-2229 10 60 BMC Plant Biology RESEARCH ARTICLE _ Open Access Genetic and transformation studies reveal negative regulation of ERS1 ethylene receptor signaling in Arabidopsis Qian Liu Chan Xu and Chi-Kuang Wen Abstract Background Ethylene receptor single mutants of Arabidopsis do not display a visibly prominent phenotype but mutants defective in multiple ethylene receptors exhibit a constitutive ethylene response phenotype. It is inferred that ethylene responses in Arabidopsis are negatively regulated by five functionally redundant ethylene receptors. However genetic redundancy limits further study of individual receptors and possible receptor interactions. Here we examined the ethylene response phenotype in two quadruple receptor knockout mutants ETR1 ersl etr2ein4ers2and ERS1 etrl etr2 ein4 ers2 to unravel the functions of ETR1 and ERS1. Their functions were also reciprocally inferred from phenotypes of mutants lacking ETR1 or ERS1. Receptor protein levels are correlated with receptor gene expression. Expression levels of the remaining wild-type receptor genes were examined to estimate the receptor amount in each receptor mutant and to evaluate if effects of ersl mutations on the ethylene response phenotype were due to receptor functional compensation. As ersl and ers2 are in the Wassilewskija Ws ecotype and etrl etr2 and ein4 are in the Columbia Col-0 ecotype possible effects of ecotype mixture on ethylene responses were also investigated. Results Ethylene responses were scored based on seedling hypocotyl measurement seedling and rosette growth and relative Chitinase B CHIB expression. Addition of ersl loss-of-function mutations to any ETRl-containing receptor mutants alleviated ethylene growth inhibition. Growth recovery by ersl mutation was reversed when the ersl mutation was complemented by ERS1p ERS1. The addition of the ers2-3 mutation to receptor mutants did not reverse the growth .