OsPFA-DSP2 Encodes a Functional Tyrosine-Specific Phosphatase, and Negatively Regulates the Responses to Xanthomonas Oryzae pv. Oryzae in Overexpressing Rice Plants

Atypical dual-specific phosphatases (PFA-DSP) is a kind of special phosphatase in plants, and play key roles in physiological processes. OsPFA-DSP2 is a member of PFA-DSP family, and negatively regulates Magnaporthe grisea responses in when overexpressed in rice. Whereas, their activity and function response to bacterial pathogen stress are still unknown. The results showed that OsPFA-DSP2 was a tyrosine-specific phosphatase, and its phosphatase activity was regulated by redox condition. The overexpressing OX13/21 lines were sensitive to Xanthomonas oryzae pv. Oryzae ( Xoo ) and enhanced the expression levels of OsCEBiP in leaves, but showed little difference on the H 2 O 2 production compared with control. Interestingly, OsPFA-DSP2 physically interacted with OsMAPK9 in vitro. These findings indicated that OsPFA-DSP2 was a tyrosine-specific phosphatase that negatively regulates Xoo response in overexpressing rice lines, which may execute through the mitogen-activated protein kinase (MAPK) signaling pathway.