OsPFA-DSP1, a rice protein tyrosine phosphatase, negatively regulates drought stress responses in transgenic tobacco and rice plants

• DOI: 10.1007/s00299-011-1220-x
• Publication Date: 2012-01-04T08:10:00Z
• Authors: Bing Liu; Jieqiong Fan; Yang Zhang; Peiqiang Mu; Peng Wang; Jianbin Su; Huihuang Lai; Shaowu Li; Dongru Feng; Jinfa Wang; Hongbin Wang
• Keywords: Genetically modified rice; Dephosphorylation

Dephosphorylation plays a pivotal role in regulating plant growth, development and abiotic/biotic stress responses. Here, we characterized a plant and fungi atypical dual-specificity phosphatase (PFA-DSP) subfamily member, OsPFA-DSP1, from rice. OsPFA-DSP1 was determined to be a functional protein tyrosine phosphatase (PTP) in vitro using phosphatase activity assays. Quantitative real-time PCR and GENEVESTIGATOR analysis showed that OsPFA-DSP1 mRNA was induced by drought stress. Transfection of rice protoplasts showed that OsPFA-DSP1 accumulated in both the cytoplasm and nucleus. Ectopic overexpression of OsPFA-DSP1 in tobacco increased sensitivity to drought stress and insensitivity to ABA-induced stomatal closure and inhibition of stomatal opening. Furthermore, overexpression of OsPFA-DSP1 in rice also increased sensitivity to drought stress. These results indicated that OsPFA-DSP1 is a functional PTP and may act as a negative regulator in drought stress responses.