RESUMO
Plant ZIP genes represent an important transporter family and may be involved in cadmium (Cd) accumulation and Cd resistance. In order to explore the function of SmZIP isolated from Salix matsudana, the roles of SmZIP in Cd tolerance, uptake, translocation, and distribution were determined in the present investigation. The transgenic SmZIP tobacco was found to respond to external Cd stress differently from WT tobacco by exhibiting a higher growth rate and more vigorous phenotype. The overexpression of SmZIP in tobacco resulted in the reduction of Cd stress-induced phytotoxic effects. Compared to WT tobacco, the Cd content of the root, stem, and leaf in the transgenic tobacco increased, and the zinc, iron, copper, and manganese contents also increased. The assimilation factor, translocation factor and bioconcentration factor of Cd were improved. The scanning electron microscopy and energy dispersive X-ray analysis results of the root maturation zone exposed to Cd for 24 h showed that Cd was transferred through the root epidermis, cortex, and vascular cylinder and migrated to the aboveground parts via the vascular cylinder, resulting in the transgenic tobacco accumulating more Cd than the WT plants. Based on the transverse section of the leaf main vein and leaf blade, Cd was transported through the vascular tissues to the leaves and accumulated more greatly in the leaf epidermis, but less in the leaf mesophyll cells, following the overexpression of SmZIP to reduce the photosynthetic toxicity. The overexpression of SmZIP resulted in the redistribution of Cd at the subcellular level, a decrease in the percentage of Cd in the cell wall, and an increase of the Cd in the soluble fraction in both the roots and leaves. It also changed the percentage composition of different Cd chemical forms by elevating the proportion of Cd extracted using 2% HAc and 0.6 mol/L HCl, but lowering that of the Cd extracted using 1 mol/L NaCl in both the leaves and roots under 10 and 100 µmol/L Cd stress for 28 d. The results implied that SmZIP played important roles in advancing Cd uptake, accumulation, and translocation, as well as in enhancing Cd resistance by altering the Cd subcellular distribution and chemical forms in the transgenic tobacco. The study will be useful for future phytoremediation applications to clean up Cd-contaminated soil.
Assuntos
Cádmio/toxicidade , Nicotiana/fisiologia , Poluentes do Solo/toxicidade , Biodegradação Ambiental , Cádmio/análise , Parede Celular/química , Genes de Plantas , Folhas de Planta/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Salix , Poluentes do Solo/análise , Nicotiana/efeitos dos fármacos , Zinco/análiseRESUMO
The Miao medical LIU's (LIU Kaiyun) infant tuina genre in western Hunan Province is one of the most famous infant tuina genres in China. Based on physiological and pathological characteristics of infants, generation-inhibition theory of five-elements and Miao medical's promotion-inhibition theory of five-meridians, the tuina protocol of "Tui Wu Jing" was flexibly adjusted; according to different constitution types, including lung-deficiency type, spleen-deficiency type, kidney-deficiency type, qi-deficiency type, yin-deficiency type, yang-deficiency type, phlegm-wet type, phlegm-heat type, different protocols were adopted to prevent or reduce the asthma recurrence and reach the aim of regulating constitution and disease prevention.
Assuntos
Asma/terapia , Prevenção Secundária/métodos , China , Humanos , Lactente , Rim , Pulmão , Medicina Tradicional Chinesa , Meridianos , Qi , Baço , Deficiência da Energia Yang , Deficiência da Energia YinRESUMO
The reinvestigation of Strychnos nux-vomica resulted in the isolation of two colorless monoquaternary bisindole alkaloids from the seeds. The structures of the two new compounds named 4-N-hydroxymethyl strychnidin-17-acetic acid (1) and 10, 11-dimethoxy-4-N-hydroxymethyl strychnidin-17-acetic acid (2), were defined by detailed spectral analyses, especially (1)H NMR, (13)C NMR, DEPT, HSQC, (1)H NMR-(1)H NMR, NOESY, HMBC and TOF-MS.