抄録
ARFs have been shown to play a central role in multiple auxin-dependent phenomena. To comprehensively understand the role of ARFs in auxin action, we have been carrying out phenotypic characterization of disruption mutants of ARF genes. Screening of T-DNA insertion lines of Arabidopsis by PCR, we have isolated a mutant line, arf8-1, in which T-DNA inserts into the third exon of ARF8 gene. arf8-1 seedlings showed the long-hypocotyl phenotype when grown in either white, red, far-red or blue light. Growth orientation of hypocotyl in wild type is randomized under red-light condition. However, arf8-1 hypocotyls grew upward in the same condition. Moreover, mature arf8-1 plants displayed longer inflorescence stem and stronger apical dominance than wild type. Introduction of ARF8 ORF driven by ARF8 promoter into arf8-1 mutant rescued the arf8-1 mutant phenotypes tested. The present results indicate that arf8-1 is a light-insensitive mutant.
