Purple acid phosphatase is important for phosphorus remobilization in plants, but its role in plant adaptation to low phosphorus availability is not known. The cDNA encoding O. sativa purple acid phosphatase (OsPAP1) has 1008 bp with an open reading frame of 335 amino acid residues. The amino acid sequence of OsPAP1 cDNA shows of 50-51% identity with other plant purple acid phosphatases. OsPAP1 was expressed in rice plants and in cell cultures in the absence of phosphate (Pi). The expression was organ-specific with the strongest expression in Pi-deprived roots. Functional expression of the OsPAP1 gene in the transgenic Arabidopsis line was confirmed by northern and western blot analysis. OsPAP1 overexpression lines had higher phosphatase activity than wild-type. Overexpression of OsPAP1 in Arabidopsis plants resulted in increased Pi accumulation under Pi sufficient condition. These results show that the OsPAP1 gene represents more efficient Pi uptake and can be used to develop new transgenic dicotyledonous plants.

• Yeon Jae Hur(College of Natural Resources and Life Science, Dong-A University)
• Young Byung Yi(College of Natural Resources and Life Science, Dong-A University)
• Tae Ho Kim(Genomics Division, Department of Agricultural Biotechnology, National Academy of Agricultural Sciences (NAAS), RDA,)
• Doh Hoon Kim(College o)