Abstract
Individual lateral root(LR) development including initiation step was positively regulated by auxin but, it was not clear how to distribute them. PUCHI, which negatively regulated the cell proliferation at early LR development, seemed to function in LR induction, as puchi had increased LRs. Some of pPUCHI::GFP expressed sites in WT differentiated into LR but the remaining lost the expression and never formed LR. PUCHI was expressed by auxin before initial cell division. Early expressed sites of auxin responsible marker DR5::GFP and Cell cycle G2/M phase marker pCyclinB1;1::GFP showed imperfect probability of LR formation. PUCHI expression marker showed the similar probability with DR5, lower than that of the cell cycle marker. It was increased in puchi as almost all PUCHI expressed sites formed LR. These results suggested that PUCHI was involved to select LR initiation sites from the auxin accumulation sites before cell division.
