Isolation of rice-Arabidopsis FOX lines that show phenotype similar to auxin over-production line.

Abstract

After screening of over c.a. 24,000 transgenic Arabidopsis plants randomly expressing the normalized rice full length cDNAs, 8 FOX mutants were isolated that mimic phenotype of over-expression of either iaaM or tms1 (bacterial IAA biosynthesis gene). When cDNAs isolated from these lines were re-transformed into Arabidopsis, transgenic plants showed the original auxin phenotype in T1 generation. These mutants were categorized into three different groups according to the auxin dose-curve response of main root. Among these 8 genes, annotations of two genes show obvious correlation with auxin synthesis (YUCCA homologue) and auxin signal transduction (IAA homologue), respectively. Function of these genes and other rice auxin gene candidates will also be discussed.