Abstract
It is believed that there are not enough number of mutants available for understanding molecular mechanism of gravity response in root. That is because root gravitropic mutants currently available do not include ones defective in the signalling pathway. Such mutants of the signalling pathways may be less defective in gravitropism. We therefore need to develop a screening system to isolate such mutants. It has been described that gravitropism in Arabidopsis roots interacts with phototropism. In this study, for isolating novel Arabidopsis mutants of root gravitropism by screening of the M2 seedlings, we developed a screening system to detect less defective phenotype in root gravitropism by using the interaction between gravitropism and phototropism. Then, we screened approximately 100,000 ethylmethanesulfonate (EMS)-mutagenized M2 seedlings of Arabidopsis and obtained 44 lines that are defective in gravitropism. In addition, we will present genetic analysis of our isolated root gravitropic mutants.
