Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive hig...Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive high-temperature adult-plant resistance gene and confers resistance to a broad spectrum of Pst races.We previously showed that WKS1 phosphorylates the thylakoid ascorbate peroxidase protein and reduces its ability to detoxify peroxides,which may contribute to the accumulation of reactive oxygen species(ROS).WKS1-mediated Pst resistance is accompanied by leaf chlorosis in Pst-infected regions,but the un-derlying mechanisms remain elusive.Here,we show that WKS1 interacts with and phosphorylates PsbO,an extrinsic member of photosystem Ⅱ(PS Ⅱ),to reduce photosynthesis,regulate leaf chlorosis,and confer Pst resistance.A point mutation in PsbO-A1 or reduction in its transcript levels by RNA interference resulted in chlorosis and reduced Pst sporulation.Biochemical analyses revealed that WKS1 phosphorylates PsbO at two conserved amino acids involved in physical interactions with PS Ⅱ and reduces the binding affinity of PsbO with PS Ⅱ.Presumably,phosphorylated PsbO proteins dissociate from the PS Ⅱ complex and then un-dergo rapid degradation by cysteine and aspartic proteases.Taken together,these results demonstrate that perturbations of wheat PsbO by point mutation or phosphorylation by WKS1 reduce the rate of photo-synthesis and delay the growth of Pst pathogen before the induction of ROS.展开更多
Deg1,a thylakoid lumen-localized protease,retains both chaperone and protease activities.The in vivo function of Deg1 has been shown to be involved not only in PSII assembly but also in the degradation of PSII reactio...Deg1,a thylakoid lumen-localized protease,retains both chaperone and protease activities.The in vivo function of Deg1 has been shown to be involved not only in PSII assembly but also in the degradation of PSII reaction center protein D1.Here we used the transgenic plants with reduced Deg1 to examine whether the lumen-localized proteins are also the substrates of Deg1 in vivo.Our results showed that the transgenic plants accumulated degradation products of the PsbO protein while the levels of full-length PsbO were not affected.The PsbO degradation products could be efficiently degraded by the recombinant Deg1.These results suggest that Deg1 is involved in the degradation of the PsbO degradation fragments,but not in the initial cleavage event itself.展开更多
The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. ...The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.展开更多
基金This research is supported by the National Key R&D Program of China(2016YFD0100500)the National Science Foundation of China(NSFC)(31772146,31972350)for J.G.J.D.acknowledges support from BARD and the Howard Hughes Medical Institute.We thank an open project for support from the National Key Laboratory of Wheat and Maize Crop Science,Henan Agricultural University.
文摘Wheat stripe rust,due to infection by Puccinia striiformis f.sp.tritici(Pst),is a devastating disease that causes significant global grain yield losses.Yr36,which encodes Wheat Kinase START1(WKS1),is an effec-tive high-temperature adult-plant resistance gene and confers resistance to a broad spectrum of Pst races.We previously showed that WKS1 phosphorylates the thylakoid ascorbate peroxidase protein and reduces its ability to detoxify peroxides,which may contribute to the accumulation of reactive oxygen species(ROS).WKS1-mediated Pst resistance is accompanied by leaf chlorosis in Pst-infected regions,but the un-derlying mechanisms remain elusive.Here,we show that WKS1 interacts with and phosphorylates PsbO,an extrinsic member of photosystem Ⅱ(PS Ⅱ),to reduce photosynthesis,regulate leaf chlorosis,and confer Pst resistance.A point mutation in PsbO-A1 or reduction in its transcript levels by RNA interference resulted in chlorosis and reduced Pst sporulation.Biochemical analyses revealed that WKS1 phosphorylates PsbO at two conserved amino acids involved in physical interactions with PS Ⅱ and reduces the binding affinity of PsbO with PS Ⅱ.Presumably,phosphorylated PsbO proteins dissociate from the PS Ⅱ complex and then un-dergo rapid degradation by cysteine and aspartic proteases.Taken together,these results demonstrate that perturbations of wheat PsbO by point mutation or phosphorylation by WKS1 reduce the rate of photo-synthesis and delay the growth of Pst pathogen before the induction of ROS.
基金supported by the State Key Basic Research Program of China(2006CB910300)the National Natural Science Foundation of China(30725003)
文摘Deg1,a thylakoid lumen-localized protease,retains both chaperone and protease activities.The in vivo function of Deg1 has been shown to be involved not only in PSII assembly but also in the degradation of PSII reaction center protein D1.Here we used the transgenic plants with reduced Deg1 to examine whether the lumen-localized proteins are also the substrates of Deg1 in vivo.Our results showed that the transgenic plants accumulated degradation products of the PsbO protein while the levels of full-length PsbO were not affected.The PsbO degradation products could be efficiently degraded by the recombinant Deg1.These results suggest that Deg1 is involved in the degradation of the PsbO degradation fragments,but not in the initial cleavage event itself.
文摘The DFT-B3LPY method, with basis set 6-31G*, is employed to calculate the structures and properties for aromatic explosives containing -NO 2 groups, nitro derivatives of benzene and nitro derivatives of aminobenzene. It is found that there is a parallel relationship between experimental impact sensitivity and bond order of the weakest C-NO 2 bond in a molecule in each series. Previously, based on semiempirical MO calculations, "the principle of the smallest bond order (PSBO) " has been proposed by us to identify the relative magnitudes of impact sensitivity of a series of explosive compounds with similar molecular structures. Here, PSBO is verified powerfully from the ab initio calculations for title compounds.
