RESUMO
Plastid intramembrane proteases in Arabidopsis (Arabidopsis thaliana) are involved in jasmonic acid biosynthesis, chloroplast development, and flower morphology. Here, we show that Ammonium-Overly-Sensitive1 (AMOS1), a member of the family of plastid intramembrane proteases, plays an important role in the maintenance of phosphate (P) homeostasis under P stress. Loss of function of AMOS1 revealed a striking resistance to P starvation. amos1 plants displayed retarded root growth and reduced P accumulation in the root compared to wild type (Col-0) under P-replete control conditions, but remained largely unaffected by P starvation, displaying comparable P accumulation and root and shoot growth under P-deficient conditions. Further analysis revealed that, under P-deficient conditions, the cell wall, especially the pectin fraction of amos1, released more P than that of wild type, accompanied by a reduction of the abscisic acid (ABA) level and an increase in ethylene production. By using an ABA-insensitive mutant, abi4, and applying ABA and ACC exogenously, we found that ABA inhibits cell wall P remobilization while ethylene facilitates P remobilization from the cell wall by increasing the pectin concentration, suggesting ABA can counteract the effect of ethylene. Furthermore, the elevated ABA level and the lower ethylene production also correlated well with the mimicked P deficiency in amos1 Thus, our study uncovers the role of AMOS1 in the maintenance of P homeostasis through ABA-antagonized ethylene signaling.
Assuntos
Proteínas de Arabidopsis/metabolismo , Cloroplastos/enzimologia , Homeostase , Metaloproteases/metabolismo , Fosfatos/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Parede Celular/efeitos dos fármacos , Parede Celular/genética , Parede Celular/metabolismo , Cloroplastos/genética , Etilenos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Metaloproteases/genética , Mutação , Pectinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse FisiológicoRESUMO
Differential optical absorption spectroscopy (DOAS) is a commonly used atmospheric pollution monitoring method. Denoising of monitoring spectral data will improve the inversion accuracy. Fourier transform filtering method is effectively capable of filtering out the noise in the spectral data. But the algorithm itself can introduce errors. In this paper, a chirp-z transform method is put forward. By means of the local thinning of Fourier transform spectrum, it can retain the denoising effect of Fourier transform and compensate the error of the algorithm, which will further improve the inversion accuracy. The paper study on the concentration retrieving of SO2 and NO2. The results show that simple division causes bigger error and is not very stable. Chirp-z transform is proved to be more accurate than Fourier transform. Results of the frequency spectrum analysis show that Fourier transform cannot solve the distortion and weakening problems of characteristic absorption spectrum. Chirp-z transform shows ability in fine refactoring of specific frequency spectrum.
