Abstract
In Arabidopsis thaliana, several lines of solid evidence have recently been provided for that the histidine kinase (AHK4/CREI/WOL) is the cytokinin receptor, which is involved in the His-Asp phosphorelay system. In the hope of gaining further insights into the complicated molecular mechanisms of the cytokinin-mediated His-Asp phosphorelay, here we employed an established Arabidopsis T87 cell line. On the one hand, we attempted to make refinements on experimental procedures for T87 cells, including optimization of growth conditions, establishment of stable transgenic lines, and monitoring transient gene expression with bioluminescence assays. Along with these attempts, on the other hand, we demonstrated that T87 cells respond exogenous cytokinin at the molecular level, showing the cytokinin-dependent induction of the type-A ARR family genes. We will discuss about the versatility of T87 cells for the study on cytokinin responses, base on the fact that a His-Asp phosphorelay signal transduction could be propagated in T87 cells.
