RESUMEN
Cell wall proteins (CWPs) are a prime site for signal perception and defense responses to environmental stresses. To gain further insights into CWPs and their molecular function, traditional techniques (e.g., two-dimensional gel electrophoresis) may be ineffective for special proteins. Elsholtzia splendens is a copper-tolerant plant species that grow on copper deposits. In this study, a fourplex isobaric tag was used for relative and absolute quantitation with liquid chromatography-tandem mass spectrometry approach to analyze the root CWPs of E. splendens. A total of 479 unique proteins were identified, including 121 novel proteins. Approximately 80.79 % of the proteins were extracted in the CaCl2 fraction, 16.08 % were detected in the NaCl fraction, and 3.13 % were identified in both fractions. The identified proteins have been involved in various processes, including cell wall remodeling, signal transduction, defense, and carbohydrate metabolism, thereby indicating a complex regulatory network in the apoplast of E. splendens roots. This study presents the first large-scale analysis of CWPs in metal-tolerant plants, which may be of paramount importance to understand the molecular functions and metabolic pathways in the root cell wall of copper-tolerant plants.
Asunto(s)
Pared Celular/metabolismo , Regulación de la Expresión Génica de las Plantas , Lamiaceae/metabolismo , Proteínas de Plantas/aislamiento & purificación , Raíces de Plantas/metabolismo , Proteoma/aislamiento & purificación , Adaptación Fisiológica , Metabolismo de los Hidratos de Carbono/genética , Pared Celular/química , Pared Celular/efectos de los fármacos , Pared Celular/genética , Fraccionamiento Químico , Cromatografía Liquida , Cobre/toxicidad , Lamiaceae/química , Lamiaceae/efectos de los fármacos , Lamiaceae/genética , Anotación de Secuencia Molecular , Inmunidad de la Planta/genética , Proteínas de Plantas/genética , Raíces de Plantas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Proteoma/genética , Transducción de Señal , Contaminantes del Suelo/toxicidad , Estrés Fisiológico , Espectrometría de Masas en TándemRESUMEN
BACKGROUND AND AIMS: Copper (Cu) is an essential micronutrient for plants. However, excess amounts of Cu are toxic and result in a wide range of harmful effects on the physiological and biochemical processes of plants. Cell wall has a crucial role in plant defense response to toxic metals. To date, the process of cell wall response to Cu and the detoxification mechanism have not been well documented at the proteomic level. METHODS: An recently developed 6-plex Tandem Mass Tag was used for relative and absolute quantitation methods to achieve a comprehensive understanding of Cu tolerance/detoxification molecular mechanisms in the cell wall. LC-MS/MS approach was performed to analyze the Cu-responsive cell wall proteins and polysaccharides. KEY RESULTS: The majority of the 22 up-regulated proteins were involved in the antioxidant defense pathway, cell wall polysaccharide remodeling, and cell metabolism process. Changes in polysaccharide amount, composition, and distribution could offer more binding sites for Cu ions. The 33 down-regulated proteins were involved in the signal pathway, energy, and protein synthesis. CONCLUSIONS: Based on the abundant changes in proteins and polysaccharides, and their putative functions, a possible protein interaction network can provide new insights into Cu stress response in root cell wall. Cu can facilitate further functional research on target proteins associated with metal response in the cell wall.
Asunto(s)
Pared Celular/metabolismo , Cobre/toxicidad , Lamiaceae/fisiología , Polisacáridos/metabolismo , Proteoma/metabolismo , Estrés Fisiológico/efectos de los fármacos , Pared Celular/efectos de los fármacos , Cromatografía Liquida , Análisis por Conglomerados , Ontología de Genes , Iones , Lamiaceae/citología , Lamiaceae/efectos de los fármacos , Lamiaceae/genética , Redes y Vías Metabólicas/efectos de los fármacos , Anotación de Secuencia Molecular , Proteínas de Plantas/metabolismo , Raíces de Plantas/citología , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Polisacáridos/aislamiento & purificación , Espectrometría de Masas en TándemRESUMEN
Occupational and experimental studies have revealed the organs most affected by dimethylformamide (DMF) are liver and gastrointestinal tract. However, few studies have focused on the potential effect of outdoor pollution of DMF. This study examined the health risk of hospitalization due to digestive system disease by time series studies in a case city Longwan, China. The urine metabolite of DMF was correlated well with DMF exposure concentration (EC). A 101.0-µg/m(3) (interquartile range) increase in the two-day moving average of DMF EC was associated with a 1.10 (1.01 Ë 1.20), 1.22 (1.10 Ë 1.35), and 1.05 (0.90 Ë 1.22) increase in hospitalization for total digestive system diseases, liver disease, and gastrointestinal tract disease, respectively. The exposure-dose response between DMF and the relative risk of liver disease was linear only below 350 µg/m(3). These findings highlight a previously unrecognized health problem related to VOCs released into the outdoor environment.