RESUMEN
Melatonin (MT) has been implicated in the plant response to phosphorus (P) stress; however, the precise molecular mechanisms involved remain unclear. This study investigated whether MT controls internal P distribution and root cell wall P remobilization in rice. Rice was treated with varying MT and P levels and analyzed using biochemical and molecular techniques to study phosphorus utilization. The results demonstrated that low P levels lead to a rapid increase in endogenous MT levels in rice roots. Furthermore, the exogenous application of MT significantly improved rice tolerance to P deficiency, as evidenced by the increased biomass and reduced proportion of roots to shoots under P-deficient conditions. MT application also mitigated the decrease in P content regardless in both the roots and shoots. Mechanistically, MT accelerated the reutilization of P, particularly in the root pectin fraction, leading to increased soluble P liberation. In addition, MT enhanced the expression of OsPT8, a gene involved in root-to-shoot P translocation. Furthermore, we observed that MT induced the production of nitric oxide (NO) in P-deficient rice roots and that the mitigating effect of MT on P deficiency was compromised in the presence of the NO inhibitor, c-PTIO, implying that NO is involved in the MT-facilitated mitigation of P deficiency in rice. Overall, our findings highlight the potential of MT as a promising strategy for enhancing rice tolerance to P deficiency and improving P use efficiency in agricultural practices.
Asunto(s)
Pared Celular , Melatonina , Óxido Nítrico , Oryza , Fósforo , Raíces de Plantas , Oryza/metabolismo , Fósforo/metabolismo , Melatonina/metabolismo , Melatonina/farmacología , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Pared Celular/metabolismo , Pared Celular/efectos de los fármacos , Óxido Nítrico/metabolismoRESUMEN
Elevated levels of cadmium (Cd) have the ability to impede plant development. Aldo-keto reductases (AKRs) have been demonstrated in a number of plant species to improve tolerance to a variety of abiotic stresses by scavenging cytotoxic aldehydes; however, only a few AKRs have been identified to improve Cd tolerance. The OsAKR1 gene was extracted and identified from rice here. After being exposed to Cd, the expression of OsAKR1 dramatically rose in both roots and shoots, although more pronounced in roots. According to a subcellular localization experiment, the nucleus and cytoplasm are where OsAKR1 is primarily found. Mutants lacking OsAKR1 exhibited Cd sensitive phenotype than that of the wild-type (WT) Nipponbare (Nip), and osakr1 mutants exhibited reduced capacity to scavenge methylglyoxal (MG). Furthermore, osakr1 mutants exhibited considerably greater hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels, and increased catalase (CAT) activity in comparison to Nip. The expression of three isomeric forms of CAT was found to be considerably elevated in osakr1 mutants during Cd stress, as demonstrated by quantitative real-time PCR analysis, when compared to Nip. These results imply that OsAKR1 controlled rice's ability to withstand Cd by scavenging harmful aldehydes and turning on the reactive oxygen species (ROS) scavenging mechanism.
Asunto(s)
Aldo-Ceto Reductasas , Cadmio , Oryza , Oryza/genética , Oryza/metabolismo , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Cadmio/toxicidad , Cadmio/metabolismo , Aldo-Ceto Reductasas/genética , Aldo-Ceto Reductasas/metabolismo , Aldehídos/metabolismo , Catalasa/metabolismo , Catalasa/genética , Aldehído Reductasa/genética , Aldehído Reductasa/metabolismo , Malondialdehído/metabolismo , Estrés Fisiológico , Piruvaldehído/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Mutación , Raíces de Plantas/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Inactivación MetabólicaRESUMEN
The precise mechanism behind the association between plants' reactions to cadmium (Cd) stress and brassinosteroid (BR) remains unclear. In the current investigation, Cd stress quickly increased the endogenous BR concentration in the rice roots. Exogenous BR also increased the hemicellulose level in the root cell wall, which in turn increased its capacity to bind Cd. Simultaneously, the transcription level of genes responsible for root Cd absorption was decreased, including Natural Resistance-Associated Macrophage Protein 1/5 (OsNRAMP1/5) and a major facilitator superfamily gene called OsCd1. Ultimately, the increased expression of Heavy Metal ATPase 3 (OsHMA3) and the decreased expression of OsHMA2, which was in charge of separating Cd into vacuoles and translocating Cd to the shoots, respectively, led to a decrease in the amount of Cd that accumulated in the rice shoots. In contrast, transgenic rice lines overexpressing OsGSK2 (a negative regulator in BR signaling) accumulated more Cd, while OsGSK2 RNA interference (RNAi) rice line accumulated less Cd. Furthermore, BR increased endogenous Gibberellic acid (GA) level, and applying GA could replicate its alleviative effect. Taken together, BR decreased Cd accumulation in rice by mediating the cell wall's fixation capacity to Cd, which might relied on the buildup of the GA.
Asunto(s)
Cadmio , Giberelinas , Oryza , Cadmio/metabolismo , Oryza/genética , Oryza/metabolismo , Brasinoesteroides , Pared Celular/metabolismo , Raíces de Plantas/metabolismoRESUMEN
We theoretically propose an optical means to detect Majorana fermions in superconducting iron (Fe) chains with a hybrid quantum dot-nanomechanical resonator system driven by two-tone fields, which is very different from the current tunneling spectroscopy experiments with electrical means. Based on the scheme, the phenomenon of Majorana modes induced transparency is demonstrated and a straightforward method to determine the quantum dot-Majorana fermions coupling strength is also presented. We further investigate the role of the nanomechanical resonator, and the resonator behaving as a phonon cavity enhances the exciton resonance spectrum, which is robust for detecting of Majorana fermions. The coherent optical spectrum affords a potential supplement to detecte Majorana fermions and supports Majorana fermions-based topological quantum computation in superconducting iron chains.
RESUMEN
BACKGROUND AND OBJECTIVE: The primary reasons for the failure were recurrence and metastasis in the treatment of gastric cancer. This study was designed to investigate the distributive regularity of EGFR, IL-6R, PCNA, DI and the diploid in the gastric cancer patients with recurrence and metastasis, to provide reliable basis to judge whether it has metastasis before operation and recurrence post operation. METHOD: Immunohistochemistry SP method and image analyzer (Fegulgen staining) were used to test the EGFR, IL-6R, PCNA, DI and the diploid in 199 patients with gastric cancer, 20 cases with normal gastric mucous membrane, and 20 cases of atypical hyperplasia. RESULTS: The level of expression of EGFR was higher in the patients with metastasis and residual gastric cancer(61.11%, 66%, 66.67%) than in the patients with other cancers, normal gastric mucous membrane, atypical hyperplasia(47.83%, 0%, 35%) (P < 0.01); In the distribution form of DNA diploid, the rate of non-diploid cells was remarkably higher in the patients with metastasis and residual gastric cancer(56.9 +/- 13.3% vs 12.8 +/- 6.3%, 0%, 12.2), and so is the DNA index (2.91 +/- 0.33 vs 2.17 +/- 0.29), but the rate of 2C cells is lower(43.8 +/- 12.9 vs 10.2 +/- 7.5, P < 0.01). CONCLUSION: EGFR, DI, and the diploid are valuable targets for judging metastasis and recurrence of gastric cancer before and after operation.