A phosphorus mutant of Arabidopsis thaliana / Bei Dong.

Abstract

In this study an EMS-mutated Arabidopsis mutant pho2, which accumulates Pi in leaves, was used to study Pi uptake and transport by comparing it to wild-type seedlings. The study aimed to define the physiological lesions in pho2 mutant and to obtain evidence regarding the function of the PHO2 gene in P nutrition in higher plants. Accumulation of Pi in leaves of pho2 was found to reside in the symplast and was not related to Zn-deficiency. The physiology of the pho2 mutant is consistent with either a block in Pi transport in phloem from shoots to roots or an inability of shoot cells to regulate internal Pi concentration. Southern block analysis revealed that the two transporter genes, APT1 and APT2 were not responsible for the pho2 mutant. Data from the mapping of the PHO2 gene along with information from the Arabidopsis genome sequencing will form the basis for cloning the PHO2 gene in the future.