Plants coordinate their development using long-distance signaling. The vascular system provides a route for long-distance movement, and specifically the xylem for root-to-shoot signaling. Root-to-shoot signals play ro...Plants coordinate their development using long-distance signaling. The vascular system provides a route for long-distance movement, and specifically the xylem for root-to-shoot signaling. Root-to-shoot signals play roles communicating soil conditions, and these signals are important for agricultural water conservation. Using genetic approaches, the Arabidopsis bypass1 （bpsl） mutant, which over-produces a root-derived signal, was identified. Although bpsl mutants have both root and shoot defects, the shoot can develop normally if the roots are removed, and the mutant root is sufficient to induce arrest of the wild-type shoot. BYPASS1 encodes a protein with no functionally characterized domains, and BPSl-like genes are found in plant genomes, but not the genomes of animals. Analyses of hormone pathways indicate that the mobile compound that arises in bpsl roots requires carotenoid biosynthesis, but it is neither abscisic acid nor strigolactone. The current model suggests that BPS1 is required to prevent the synthesis of a novel substance that moves from the root to the shoot, where it modifies shoot growth by interfering with auxin signaling.展开更多
Objective To testify the lung injury induced by cardiopulmonary bypass(CPB) in canine model and observe the influence of CPB on the aquaporin 1 (AQP1) mRNA expression in canine lung. Methods 8 mongrel dogs were used t...Objective To testify the lung injury induced by cardiopulmonary bypass(CPB) in canine model and observe the influence of CPB on the aquaporin 1 (AQP1) mRNA expression in canine lung. Methods 8 mongrel dogs were used to perform the cardiopulmonary bypass. The hearts arrested for 90 minutes with mild hypothermia and rebeated for 6 hours. The hemodynamics,the ratio of lung dry weight and wet weight,the plasmic展开更多
Plants adjust their development in relation to the availability of nutrient sources. This necessitates signal- ing between root and shoot. Aside from the well-known systemic signaling processes mediated by auxin, cyto...Plants adjust their development in relation to the availability of nutrient sources. This necessitates signal- ing between root and shoot. Aside from the well-known systemic signaling processes mediated by auxin, cytokinin, and sugars, new pathways involving carotenoid-derived hormones have recently been identified. The auxin-responsive MAX pathway controls shoot branching through the biosynthesis of strigolactone in the roots. The BYPASSI gene affects the production of an as-yet unknown carotenoid-derived substance in roots that promotes shoot development. Novel local and systemic mechanisms that control adaptive root development in response to nitrogen and phosphorus starvation were recently discovered. Notably, the ability of the NITRATE TRANSPORTER 1.1 to transport auxin drew for the first time a functional link between auxin, root development, and nitrate availability in soil. The study of plant response to phos- phorus starvation allowed the identification of a systemic mobile miRNA. Deciphering and integrating these signaling pathways at the whole-plant level provide a new perspective for understanding how plants regulate their development in response to environmental cues.展开更多
基金the USDA and the NSF for awards to LES that supported this work (NSF IOS 0922288 and USDA award 20083530404488)
文摘Plants coordinate their development using long-distance signaling. The vascular system provides a route for long-distance movement, and specifically the xylem for root-to-shoot signaling. Root-to-shoot signals play roles communicating soil conditions, and these signals are important for agricultural water conservation. Using genetic approaches, the Arabidopsis bypass1 （bpsl） mutant, which over-produces a root-derived signal, was identified. Although bpsl mutants have both root and shoot defects, the shoot can develop normally if the roots are removed, and the mutant root is sufficient to induce arrest of the wild-type shoot. BYPASS1 encodes a protein with no functionally characterized domains, and BPSl-like genes are found in plant genomes, but not the genomes of animals. Analyses of hormone pathways indicate that the mobile compound that arises in bpsl roots requires carotenoid biosynthesis, but it is neither abscisic acid nor strigolactone. The current model suggests that BPS1 is required to prevent the synthesis of a novel substance that moves from the root to the shoot, where it modifies shoot growth by interfering with auxin signaling.
文摘Objective To testify the lung injury induced by cardiopulmonary bypass(CPB) in canine model and observe the influence of CPB on the aquaporin 1 (AQP1) mRNA expression in canine lung. Methods 8 mongrel dogs were used to perform the cardiopulmonary bypass. The hearts arrested for 90 minutes with mild hypothermia and rebeated for 6 hours. The hemodynamics,the ratio of lung dry weight and wet weight,the plasmic
文摘Plants adjust their development in relation to the availability of nutrient sources. This necessitates signal- ing between root and shoot. Aside from the well-known systemic signaling processes mediated by auxin, cytokinin, and sugars, new pathways involving carotenoid-derived hormones have recently been identified. The auxin-responsive MAX pathway controls shoot branching through the biosynthesis of strigolactone in the roots. The BYPASSI gene affects the production of an as-yet unknown carotenoid-derived substance in roots that promotes shoot development. Novel local and systemic mechanisms that control adaptive root development in response to nitrogen and phosphorus starvation were recently discovered. Notably, the ability of the NITRATE TRANSPORTER 1.1 to transport auxin drew for the first time a functional link between auxin, root development, and nitrate availability in soil. The study of plant response to phos- phorus starvation allowed the identification of a systemic mobile miRNA. Deciphering and integrating these signaling pathways at the whole-plant level provide a new perspective for understanding how plants regulate their development in response to environmental cues.
