RESUMEN
Background: The prevalence of metabolic-associated steatotic liver disease (MASLD) is rising precipitously among children, particularly in regions or countries burdened with high prevalence of obesity. However, identifying those at high risk remains a significant challenge, as the majority do not exhibit distinct symptoms of MASLD. There is an urgent need for a widely accepted non-invasive predictor to facilitate early disease diagnosis and management of the disease. Our study aims to 1) evaluate and compare existing predictors of MASLD, and 2) develop a practical screening strategy for children, tailored to local prevalence of obesity. Methods: We utilized a school-based cross-sectional survey in Beijing as the training dataset to establish predictive models for screening MASLD in children. An independent school-based study in Ningbo was used to validate the models. We selected the optimal non-invasive MASLD predictor by comparing logistic regression model, random forest model, decision tree model, and support vector machine model using both the Beijing and Ningbo datasets. This was followed by serial testing using the best performance index we identified and indices from previous studies. Finally, we calculated the potential MASLD screening recommendation categories and corresponding profits based on national and subnational obesity prevalence, and applied those three categories to 200 countries according to their obesity prevalence from 1990 to 2022. Findings: A total of 1018 children were included (NBeijing = 596, NNingbo = 422). The logistic regression model demonstrated the best performance, identifying the waist-to-height ratio (WHtR, cutoff value ≥0.48) as the optimal noninvasive index for predicting MASLD, with strong performance in both training and validation set. Additionally, the combination of WHtR and lipid accumulation product (LAP) was selected as an optimal serial test to improve the positive predictive value, with a LAP cutoff value of ≥668.22 cm × mg/dL. Based on the obesity prevalence among 30 provinces, three MASLD screening recommendations were proposed: 1) "Population-screening-recommended": For regions with an obesity prevalence ≥12.0%, where MASLD prevalence ranged from 5.0% to 21.5%; 2) "Resources-permitted": For regions with an obesity prevalence between 8.4% and 12.0%, where MASLD prevalence ranged from 2.3% to 4.4%; 3) "Population-screening-not-recommended": For regions with an obesity prevalence <8.4%, where MASLD prevalence is difficult to detect using our tool. Using our proposed cutoff for screening MASLD, the number of countries classified into the "Population-screening-recommended" and "Resources-permitted" categories increased from one and 11 in 1990 to 95 and 28 in 2022, respectively. Interpretation: WHtR might serve as a practical and accessible index for predicting pediatric MASLD. A WHtR value ≥0.48 could facilitate early identification and management of MASLD in areas with obesity prevalence ≥12.0%. Furthermore, combining WHtR ≥0.48 with LAP ≥668.22 cm × mg/dL is recommended for individual MASLD screening. Moreover, linking these measures with population obesity prevalence not only helps estimate MASLD prevalence but also indicates potential screening profits in regions at varying levels of obesity risk. Funding: This study was supported by grants from Capital's Funds for Health Improvement and Research (Grant No. 2022-1G-4251), National Natural Science Foundation of China (Grant No. 82273654), Major Science and Technology Projects for Health of Zhejiang Province (Grant No. WKJ-ZJ-2216), Cyrus Tang Foundation for Young Scholar 2022 (2022-B126) and Sino-German Mobility Programme (M-0015).
RESUMEN
Starch biosynthesis during rice endosperm development is important for grain quality, as it influences grain size and physico-chemical properties, which together determine rice eating quality. Cereal starch biosynthetic pathways have been comprehensively investigated; however, their regulation, especially by transcriptional repressors remains largely unknown. Here, we identified a DUF1645 domain-containing protein, STRESS_tolerance and GRAIN_LENGTH (OsSGL), that participates in regulating rice starch biosynthesis. Overexpression of OsSGL reduced total starch and amylose content in the endosperm compared with the wild type. Chromatin immunoprecipitation sequencing and RNA-seq analyses indicated that OsSGL targets the transcriptional activity of several starch and sucrose metabolism genes. In addition, ChIP-qPCR, yeast one-hybrid, EMSA and dual-luciferase assays demonstrated that OsSGL directly inhibits the expression of SUCROSE SYNTHASE 1 (OsSUS1) in the endosperm. Furthermore, OsSUS1 interacts with OsSGL to release its transcriptional repression ability. Unexpectedly, our results also show that knock down and mutation of OsSGL disrupts the starch biosynthetic pathway, causing lower starch and amylose content. Therefore, our findings demonstrate that accurate control of OsSGL homeostasis is essential for starch synthesis and grain quality. In addition, we revealed the molecular mechanism of OsSGL in regulating starch biosynthesis-related genes, which are required for grain quality.
Asunto(s)
Oryza , Amilosa/metabolismo , Grano Comestible , Endospermo/genética , Endospermo/metabolismo , Regulación de la Expresión Génica de las Plantas , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Almidón/metabolismo , Factores de Transcripción/metabolismoRESUMEN
Receptor-like cytoplasmic kinases (RLCKs) have been demonstrated to be involved in the regulation of growth, development, and pathogen responses in plants. However, the identity of RLCKs involved in abiotic tolerance remains elusive. In this study, we present data on OsRLCK241, a receptor-like cytoplasmic kinase that is induced by salt and drought stresses. Subcellular localization revealed the presence of an OsRLCK241-GFP fusion protein at the plasma membrane. Under normal conditions, we did not observe any measurable discrepancies between the development and growth of WT and OsRLCK241 transgenic plants. In OsRLCK241 transgenic plants, the overexpression of OsRLCK241 conferred improved tolerance to salt and drought stresses. OsRLCK241 expression improved ROS detoxification by enhancing the activities of ROS scavengers as well as the accumulation of compatible osmolytes to alleviate the osmotic stress evoked by salt and drought stresses. Additionally, several stress-responsive genes showed higher expression levels in OsRLCK241 transgenic plants upon exposure to salt and drought conditions. Collectively, our observations suggest that OsRLCK241 improved salt and drought tolerance in rice is mainly due to improved ROS detoxification, increased accumulation of osmolytes, and altered expression of stress-responsive genes.
Asunto(s)
Regulación de la Expresión Génica de las Plantas/genética , Presión Osmótica/fisiología , Proteínas Tirosina Quinasas/genética , Estrés Fisiológico/fisiología , Sequías , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Proteínas de la Membrana/genética , Oryza/genética , Oryza/metabolismo , Tolerancia a la Sal/genética , Cloruro de Sodio/farmacologíaRESUMEN
BACKGROUND: Rice is the staple food of many people around the world. However, most rice varieties, especially widely grown indica varieties and hybrids, are sensitive to cold stress. In order to provide a basis for the utilization of a common wild rice (CWR, Oryza rufipogon Griff.) named 'Chaling' CWR in cold-tolerant rice breeding and deepen the understanding of rice cold tolerance, the cold tolerance of ratoon 'Chaling' CWR was studied under the stress of the natural low temperature in winter in Changsha, Hunan province, China, especially under the stress of abnormal natural low temperature in Changsha in 2008, taking other ratoon CWR accessions and ratoon cultivated rice phenotypes as control. RESULTS: The results showed that ratoon 'Chaling' CWR can safely overwinter under the natural conditions in Changsha (28° 22' N), Hunan province, China, which is a further and colder northern place than its habitat, even if it suffers a long-term low temperature stress with ice and snow. In 2008, an extremely cold winter appeared in Changsha, i.e., the average daily mean temperature of 22 consecutive days from January 13 to February 3 was - 1.0 °C, and the extreme low temperature was - 4.7 °C. After subjected to this long-term cold stress, the overwinter survival rate of ratoon 'Chaling' CWR was 100%, equals to that of ratoon 'Dongxiang' CWR which is northernmost distribution in the word among wild rice populations, higher than those of ratoon 'Fusui' CWR, ratoon 'Jiangyong' CWR, and ratoon 'Liujiang' CWR (63.55-83.5%) as well as those of ratoon 'Hainan' CWR, ratoon 'Hepu' CWR, and all the ratoon cultivated rice phenotypes including 3 japonica ones, 3 javanica ones, and 5 indica ones (0.0%). CONCLUSIONS: The results indicate that ratoon 'Chaling' CWR possesses strong cold tolerance and certain freezing tolerance.
Asunto(s)
Adaptación Fisiológica/fisiología , Frío , Respuesta al Choque por Frío/fisiología , Oryza/fisiología , Fenotipo , Estaciones del AñoRESUMEN
BACKGROUND: Rice is the staple food of many people around the world. However, most rice varieties, especially widely grown indica varieties and hybrids, are sensitive to cold stress. In order to provide a basis for the utilization of a common wild rice (CWR, Oryza rufipogon Griff.) named 'Chaling' CWR in cold-tolerant rice breeding and deepen the understanding of rice cold tolerance, the cold tolerance of ratoon 'Chaling' CWR was studied under the stress of the natural low temperature in winter in Changsha, Hunan province, China, especially under the stress of abnormal natural low temperature in Changsha in 2008, taking other ratoon CWR accessions and ratoon cultivated rice phenotypes as control. RESULTS: The results showed that ratoon 'Chaling' CWR can safely overwinter under the natural conditions in Changsha (28° 22' N), Hunan province, China, which is a further and colder northern place than its habitat, even if it suffers a long-term low temperature stress with ice and snow. In 2008, an extremely cold winter appeared in Changsha, i.e., the average daily mean temperature of 22 consecutive days from January 13 to February 3 was - 1.0 °C, and the extreme low temperature was - 4.7 °C. After subjected to this long-term cold stress, the overwinter survival rate of ratoon 'Chaling' CWR was 100%, equals to that of ratoon 'Dongxiang' CWR which is northernmost distribution in the word among wild rice populations, higher than those of ratoon 'Fusui' CWR, ratoon 'Jiangyong' CWR, and ratoon 'Liujiang' CWR (63.55-83.5%) as well as those of ratoon 'Hainan' CWR, ratoon 'Hepu' CWR, and all the ratoon cultivated rice phenotypes including 3 japonica ones, 3 javanica ones, and 5 indica ones (0.0%). CONCLUSIONS: The results indicate that ratoon 'Chaling' CWR possesses strong cold tolerance and certain freezing tolerance.
Asunto(s)
Oryza/fisiología , Adaptación Fisiológica/fisiología , Frío , Respuesta al Choque por Frío/fisiología , Fenotipo , Estaciones del AñoRESUMEN
Copper is a mineral element essential for the normal growth and development of plants; however, excessive levels can severely affect plant growth and development. Oryza sativa L. multiple stress-responsive gene 3 (OsMSR3) is a small, low-molecular-weight heat shock protein (HSP) gene. A previous study has shown that OsMSR3 expression improves the tolerance of Arabidopsis to cadmium stress. However, the role of OsMSR3 in the Cu stress response of plants remains unclear, and, thus, this study aimed to elucidate this phenomenon in Arabidopsis thaliana, to further understand the role of small HSPs (sHSPs) in heavy metal resistance in plants. Under Cu stress, transgenic A. thaliana expressing OsMSR3 showed higher tolerance to Cu, longer roots, higher survival rates, biomass, and relative water content, and accumulated more Cu, abscisic acid (ABA), hydrogen peroxide, chlorophyll, carotenoid, superoxide dismutase, and peroxidase than wild-type plants did. Moreover, OsMSR3 expression in A. thaliana increased the expression of antioxidant-related and ABA-responsive genes. Collectively, our findings suggest that OsMSR3 played an important role in regulating Cu tolerance in plants and improved their tolerance to Cu stress through enhanced activation of antioxidative defense mechanisms and positive regulation of ABA-responsive gene expression.
Asunto(s)
Adaptación Fisiológica , Arabidopsis/fisiología , Cobre/toxicidad , Proteínas de Choque Térmico Pequeñas/metabolismo , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Estrés Fisiológico , Ácido Abscísico/metabolismo , Adaptación Fisiológica/efectos de los fármacos , Adaptación Fisiológica/genética , Antioxidantes/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Carotenoides/metabolismo , Clorofila/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Proteínas de Choque Térmico Pequeñas/genética , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Oryza/efectos de los fármacos , Oryza/genética , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Estrés Fisiológico/efectos de los fármacos , Estrés Fisiológico/genéticaRESUMEN
Phosvitin phosphopeptides (PPP) effectively enhanced calcium bioavailability via inhibiting calcium-phosphate deposition. It is difficult to hydrolyze native phosvitin (PSV) to release PPP due to its compact structure. Polysaccharide conjugation could improve the biofunctional properties of proteins via altering their structures. In this research, PSV was subjected to conjugation with pectin, and changes in physicochemical characteristics and functionalities were determined. The results showed that PSV underwent an unfolding process when conjugated with pectin at a mass ratio of 1 : 2, exposing more hydrophobic groups. Excessive glycosylation induced a refolded structure with a lower surface hydrophobicity and a higher thermal stability. These secondary and tertiary structural changes improved the emulsifying properties of PSV and allowed the production of emulsions with smaller oil droplets. Simultaneously, due to redistribution of phosphate groups, the PPP derived from copolymers exhibited a stronger calcium binding capacity, especially at a mass ratio of 1 : 6, possessing a potential to be utilized in functional foods.
Asunto(s)
Calcio/química , Emulsionantes/química , Pectinas/química , Fosfopéptidos/química , Fosvitina/química , Animales , Pollos , Yema de Huevo/química , Emulsiones/química , Calor , HidrólisisRESUMEN
Small signaling peptides play important roles in plant development and responses to abiotic and biotic stresses. We have identified a novel small peptide gene in rice, OsDSSR1, which is expressed mainly in the root, stem, node, leaf, and panicle. OsDSSR1 expression is also induced by drought, salinity, ABA, and H2O2 treatment. OsDSSR1 is localized in the nucleus and cytoplasm. Transgenic plants overexpressing OsDSSR1 exhibited enhanced drought stress tolerance and decreased ABA sensitivity as compared to the wild type. Overexpression of OsDSSR1 promoted the accumulation of compatible osmolytes, such as free proline and soluble sugars. OsDSSR1-overexpressing plants displayed enhanced OsSodCc2 and OscAPX expression and superoxide dismutase and ascorbate peroxidase activities under drought stress. RNA-sequencing data revealed that the expression of 72 abiotic stress-responsive genes was significantly altered in homozygous transgenic plants. These stress-responsive candidate genes will aid in expanding our understanding of the mechanisms by which small peptides mediate tolerance in crop species.
Asunto(s)
Ácido Abscísico/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Oryza/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Secuencia de Aminoácidos , Sequías , Expresión Génica , Genes Reporteros , Peróxido de Hidrógeno/farmacología , Péptidos y Proteínas de Señalización Intracelular/genética , Oryza/citología , Oryza/efectos de los fármacos , Oryza/fisiología , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente , Prolina/metabolismo , Plantones/citología , Plantones/efectos de los fármacos , Plantones/genética , Plantones/fisiología , Alineación de Secuencia , Estrés Fisiológico , Azúcares/metabolismoRESUMEN
The MYB proteins play important roles in regulating plant responses to environmental stresses. We cloned and functionally characterized a novel MYB-related gene, OsMYBR1, from rice. Our microarray and qRT-PCR analyses showed that its expression was induced by drought and cold in different tissues at various developmental stages. This gene encodes a putative MYB-related protein of 463 amino acid residues. Compared with wild-type (WT) plants, transgenic plants over-expressing OsMYBR1 exhibited much greater tolerance to drought stress and decreased sensitivity to abscisic acid (ABA). Under drought treatment, levels of free proline and soluble sugar were higher in transgenic plants than in the WT. Furthermore, transcriptional expression of four stress-related genes -- OsP5CS1, OsProt, OsLEA3, and OsRab16 -- was significantly increased in transgenic plants under drought stressed conditions and ABA. Our results provide evidence that OsMYBR1 is involved in mediating plant responses to ABA and drought.
Asunto(s)
Ácido Abscísico/metabolismo , Adaptación Fisiológica/genética , Regulación de la Expresión Génica de las Plantas , Oryza/genética , Plantas Modificadas Genéticamente , Factores de Transcripción/genética , Ácido Abscísico/farmacología , Frío , Sequías , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Glutamato-5-Semialdehído Deshidrogenasa/genética , Glutamato-5-Semialdehído Deshidrogenasa/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Análisis por Micromatrices , Oryza/efectos de los fármacos , Oryza/crecimiento & desarrollo , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transducción de Señal , Estrés Fisiológico , Factores de Transcripción/metabolismo , Tricomas/efectos de los fármacos , Tricomas/genética , Tricomas/crecimiento & desarrollo , Tricomas/metabolismoRESUMEN
KEY MESSAGE: Autotetraploid Arabidopsis line esd and 4COL exhibit enhanced tolerance to Cu stress by enhancing activation of antioxidative defenses, altering expression of genes related to Cu transport, chelation, and ABA-responsive. Autopolyploidy is ubiquitous among angiosperms and often results in better adaptation to stress conditions. Although copper (Cu) is an essential trace element, excess amounts can inhibit plant growth and even result in death. Here, we report that autotetraploid Arabidopsis thaliana esd and 4COL exhibit higher tolerance to Cu stress. Under such conditions, tetraploid plants had lower Cu contents and significantly more biomass compared with diploid plants. When exposed to excess Cu for 24 h, levels of superoxide anions, hydrogen peroxide, and malondialdehyde were lower in tetraploids than in diploids. Moreover, activities of the antioxidant enzymes superoxide dismutase and peroxidase were stimulated and glutathione content was maintained at a relative higher level in the tetraploids. The expression of genes related to Cu transport and chelation was altered in autotetraploid Arabidopsis under Cu stress, and several key genes involved in the response to abscisic acid (ABA) were significantly up-regulated. Our results indicate that tetraploid Arabidopsis esd and 4COL acquire improved tolerance to Cu stress through enhanced activation of antioxidative defense mechanisms, altered expression of genes related to Cu transport and chelation, and positive regulation of expression for ABA-responsive genes.
Asunto(s)
Adaptación Fisiológica/efectos de los fármacos , Arabidopsis/efectos de los fármacos , Cobre/farmacología , Estrés Fisiológico/efectos de los fármacos , Tetraploidía , Ácido Abscísico/farmacología , Adaptación Fisiológica/genética , Antioxidantes/metabolismo , Arabidopsis/genética , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Glutatión/metabolismo , Peróxido de Hidrógeno/metabolismo , Malondialdehído/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Superóxido Dismutasa/metabolismo , Superóxidos/metabolismoRESUMEN
Abiotic stress seriously affects the yield of rice (Oryza sativa L.). Grain yield in rice is multiplicatively determined by the number of panicles, number of grains per panicle, and grain weight. Here, we describe the molecular and functional characterization of STRESS_tolerance and GRAIN_LENGTH (OsSGL), a rice gene strongly up-regulated by a wide spectrum of abiotic stresses. OsSGL encodes a putative member of the DUF1645 protein family of unknown function. Overexpression of OsSGL significantly altered certain development processes greatly and positively affecting an array of traits in transgenic rice plants, including increased grain length, grain weight and grain number per panicle, resulting in a significant increase in yield. Microscopical analysis showed that the enhanced OsSGL expression promoted cell division and grain filling. Microarray and quantitative real-time PCR (qRT-PCR) analyses revealed that a large number of genes involved in stress-response, cell cycle and cytokinin signaling processes were induced or suppressed in OsSGL-overexpressing plants. Together, our results suggest that OsSGL may regulate stress-tolerance and cell growth by acting via a cytokinin signaling pathway. This study not only contributes to our understanding of the underlying mechanism regulating rice stress-tolerance and grain length, but also provides a strategy for tailor-made crop yield improvement.
Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Oryza , Proteínas de Plantas , Semillas , Estrés Fisiológico , Regulación hacia Arriba , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/biosíntesis , Proteínas de Plantas/genética , Semillas/genética , Semillas/metabolismoRESUMEN
Drought is a major environmental factor that limits plant growth and crop productivity. Genetic engineering is an effective approach to improve drought tolerance in various crops, including rice (Oryza sativa). Functional characterization of relevant genes is a prerequisite when identifying candidates for such improvements. We investigated OsSGL (Oryza sativa Stress tolerance and Grain Length), a novel DUF1645 domain-containing protein from rice. OsSGL was up-regulated by multiple stresses and localized to the nucleus. Transgenic plants over-expressing or hetero-expressing OsSGL conferred significantly improved drought tolerance in transgenic rice and Arabidopsis thaliana, respectively. The overexpressing plants accumulated higher levels of proline and soluble sugars but lower malondialdehyde (MDA) contents under osmotic stress. Our RNA-sequencing data demonstrated that several stress-responsive genes were significantly altered in transgenic rice plants. We unexpectedly observed that those overexpressing rice plants also had extensive root systems, perhaps due to the altered transcript levels of auxin- and cytokinin-associated genes. These results suggest that the mechanism by which OsSGL confers enhanced drought tolerance is due to the modulated expression of stress-responsive genes, higher accumulations of osmolytes, and enlarged root systems.
RESUMEN
OBJECTIVE: To analyze the clinical data and result of voiding cystourethrography (VCUG) in high-risk children with vesicoureteral reflux (VUR) for better awareness of VUR, and to assess the usefulness of non-radioactive voiding ultrasonography (VUS) in the diagnosis of VUR. METHOD: Ninety-three high-risk children with VUR who were hospitalized from July 2007 to April 2010 were studied. The study included 58 cases of urinary tract infection (UTI) and 35 cases of fetal or postnatal hydronephrosis detected on a B ultrasound scan. The results of urinalysis, urine culture, renal function, B ultrasound and VCUG were evaluated. Part of patients underwent VUS followed by VCUG immediately. RESULT: (1) Sixty-two boys and 31 girls (aged 1 month to 11.5 years, mean age 2 years) were included. VUR was detected in 26 patients (28%) by VCUG. In terms of kidney-ureter units, VUR was detected in 36 of 186 kidney-ureter units, including 6 grade I, 3 grade II, 6 grade III, 15 grade IV and 6 grade V. (2) VUR was detected in 20 of 58 UTI patients (34.5%) by VCUG. The proportion of VUR in recurrent UTI group was 61.1%, much higher than that in first UTI group (22.5%). Thirteen of 20 VUR (65%) occurred in UTI patients under 1 year of age (M/F 10/3), with more bilateral VUR and severe grades of VUR than the older group. VUR was detected in 6 of 35 fetal or postnatal hydronephrosis patients (17.1%) by VCUG. (3) Twenty-two patients underwent both VUS and VCUG. VUR was detected in 4 patients and 6 kidney-ureter units by VCUG, while in 6 patients and 9 kidney-ureter units by VUS. Taking VCUG as the reference standard, VUS had a sensitivity of 100%, specificity of 92.1%, positive predictive value of 66.7%, and negative predictive value of 100%. There was a concordance rate of 93.2% between VUS and VCUG. CONCLUSION: It is important to early screen VUR in UTI, fetal or postnatal hydronephrosis patients. There are more VUR, especially more bilateral VUR and severe grades of VUR, occurred in UTI patients under 1 year of age compared to older children. The incidence of VUR in recurrent UTI group was much higher than that in first UTI group. VUS is an accurate, reliable and radiation-free technique for the detection of VUR. It could be used to screen high-risk children for VUR and do the evaluation in the follow-up of VUR.
Asunto(s)
Reflujo Vesicoureteral/diagnóstico , Niño , Preescolar , Diagnóstico por Imagen , Femenino , Humanos , Hidronefrosis/diagnóstico , Hidronefrosis/diagnóstico por imagen , Lactante , Masculino , Ultrasonografía , Infecciones Urinarias/diagnóstico , Infecciones Urinarias/diagnóstico por imagen , Urografía , Reflujo Vesicoureteral/diagnóstico por imagenRESUMEN
Many abiotic stimuli, such as drought and salt stresses, elicit changes in intracellular calcium levels that serve to convey information and activate adaptive responses. Ca²âº signals are perceived by different Ca²âº sensors, and calmodulin (CaM) is one of the best-characterized Ca²âº sensors in eukaryotes. Calmodulin-like (CML) proteins also exist in plants, but their functions at the physiological and molecular levels are largely unknown. In this report, we present data on OsMSR2 (Oryza sativa L. Multi-Stress-Responsive gene 2), a novel calmodulin-like protein gene isolated from rice Pei'ai 64S (Oryza sativa L.). Expression of OsMSR2 was strongly up-regulated by a wide spectrum of stresses, including cold, drought, and heat in different tissues at different developmental stages of rice, as revealed by both microarray and quantitative real-time RT-PCR analyses. Analysis of the recombinant OsMSR2 protein demonstrated its potential ability to bind Ca²âº in vitro. Expression of OsMSR2 conferred enhanced tolerance to high salt and drought in Arabidopsis (Arabidopsis thaliana) accompanied by altered expression of stress/ABA-responsive genes. Transgenic plants also exhibited hypersensitivity to ABA during the seed germination and post-germination stages. The results suggest that expression of OsMSR2 modulated salt and drought tolerance in Arabidopsis through ABA-mediated pathways.