Abstract: For systematic functional analysis of
genes, we attempted the application of the
FOX-hunting system to super growing-roots (SR)
of legume species Lotus corniculatus which was
previously reported by Himuro et al. (2011). In
this study, we investigated the functional
analysis of FSL#35, which was expressed by the
rolB gene derived from the Agrobacterium
rhizogenes Ri plasmid. In monoculture roots
grown in liquid media, the FSL#35 showed
specific phenotypes that increased root length,
lateral root number and root surface area
compared with SR. These enhanced phenotypes
of FSL#35 were caused by cell profile alteration,
while increased total root length and increased
lateral root number were caused by the
expansion of cortex cells and increased pericycle
cells, respectively. In addition, the FSL#35 root
showed high and specific respiration activity
compared with SR. These results suggest that
distinct cell profiles of FSL#35 were induced by
the alteration of respiration activity in root tissue.
The enhanced root growth in the FSL#35 root
might be induced by alteration of ROS
metabolisms. Investigating the details of the rolB
gene function, for example by phytohormone
analysis, will elucidate the novel benefits of the
rolB gene for agriculture.