Abstract
Auxin (IAA) plays an important role in lateral root formation and gravitropism in roots. The AUX1 protein has been shown to act as an auxin (IAA) influx carrier by its expression in Xenopus oocytes. (Yang et al, 2006) However, it is difficult to measure AUX1 uptake directly in intact plants, because apparent 3H-IAA uptake obtained by scintillation counter contains additional factors: 3H-IAA absorbed in cell wall and uptake by diffusion. For this reason, simple method for estimating net 3H-IAA uptake has been awaited for a long time.
Here, we wish to show a new methodology to calculate net 3H-IAA uptake in intact plants: we have estimated the amount of 3H-IAA absorbed in cell wall and uptake by diffusion on the basis of the individual pH dependency.
