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1.
Environ Sci Technol ; 55(13): 8730-8741, 2021 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-34169723

RESUMEN

Perfluorooctanesulfonate (PFOS) as an accumulative emerging persistent organic pollutant in crops poses severe threats to human health. Lettuce varieties that accumulate a lower amount of PFOS (low-accumulating crop variety, LACV) have been identified, but the regarding mechanisms remain unsolved. Here, rhizospheric activation, uptake, translocation, and compartmentalization of PFOS in LACV were investigated in comparison with those of high-accumulating crop variety (HACV) in terms of rhizospheric forms, transporters, and subcellular distributions of PFOS. The enhanced PFOS desorption from the rhizosphere soils by dissolved organic matter from root exudates was observed with weaker effect in LACV than in HACV. PFOS root uptake was controlled by a transporter-mediated passive process in which low activities of aquaporins and rapid-type anion channels were corrected with low expression levels of PIPs (PIP1-1 and PIP2-2) and ALMTs (ALMT10 and ALMT13) genes in LACV roots. Higher PFOS proportions in root cell walls and trophoplasts caused lower root-to-shoot transport in LACV. The ability to cope with PFOS toxicity to shoot cells was poorer in LACV relative to HACV since PFOS proportions were higher in chloroplasts but lower in vacuoles. Our findings provide novel insights into PFOS accumulation in lettuce and further understanding of multiprocess mechanisms of LACV.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes del Suelo , Fluorocarburos/análisis , Humanos , Lactuca , Suelo , Contaminantes del Suelo/análisis
2.
Planta Med ; 85(16): 1275-1286, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31627219

RESUMEN

Breast cancer is one of the most common cancers diagnosed among women worldwide. Estrogen receptor alpha (ERα) is a transcriptional factor that plays an important role in the development and progression of breast cancer. Yuanhuatine, a natural daphnane-type diterpenoid extracted from Daphne genkwa, was reported to exhibit significant cytotoxicity against breast cancer cells. However, the underlying mechanism is still unclear. In this study, we evaluated the cytotoxicity of yuanhuatine on two breast cancer cell lines that are ERα-positive and -negative. The results show that yuanhuatine inhibits the growth of ERα-positive cells (MCF-7) with much stronger inhibitory activity (IC50 = 0.62 µM) compared with positive control tamoxifen (IC50 = 14.43 µM). However, no obvious cytotoxicity was observed in ERα-negative cells (MDA-MB-231). Subsequent experiment also indicated that yuanhuatine markedly induced mitochondrial dysfunction, leading to apoptosis in MCF-7 cells. Molecular docking studies suggest the potential interactions between yuanhuatine and ERα. Immunofluorescence staining and Western blot analysis indicated that yuanhuatine down-regulated the expression of ERα in MCF-7 cells. MPP, a specific ERα inhibitor, significantly enhanced yuanhuatine-induced mitochondrial dysfunction and apoptosis in MCF-7 cells. On the contrary, the treatment with yuanhuatine causes no apoptosis in MM231 cells. Altogether, in vitro and in silico results suggested that ERα down-regulation was involved in yuanhuatine-induced mitochondrial dysfunction and apoptosis in ERα-positive breast cancer cells. Thus, yuanhuatine could be a potential candidate for treating ERα-positive breast cancer.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Daphne/química , Tamoxifeno/farmacología , Antineoplásicos Fitogénicos/química , Proliferación Celular/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Femenino , Humanos , Células MCF-7 , Mitocondrias/metabolismo , Simulación del Acoplamiento Molecular , Tamoxifeno/química
3.
J Asian Nat Prod Res ; 21(7): 666-672, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29888617

RESUMEN

Phytochemical investigation of Croton crassifolius roots afforded five sesquiterpenes (1-5), including two new sesquiterpenes 6S-hydroxy-cyperenoic acid (1) and crassifterpenoid A (5), together with three known compounds (2-4). The structures of the new compounds were determined by comprehensive spectroscopic methods, and their absolute configurations were determined by quantum chemical ECD calculation. Crassifterpenoid A (5) is the first germacrane-type sesquiterpene isolated from C. crassifolius, which enriched the diversity of chemical constituents in Croton crassifolius. In addition, the cytotoxicities of all compounds against human liver cancer lines HepG2 and Hep3B were determined, but none showed significant activity.


Asunto(s)
Croton/química , Raíces de Plantas/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Dicroismo Circular , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Resultados Negativos , Extractos Vegetales/química
4.
Bull Environ Contam Toxicol ; 102(4): 589-594, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30788561

RESUMEN

Cadmium (Cd) is one of the hazardous environmental pollutants, and it can be harmful to human health through consumption of food-plants capable of bioaccumulating Cd. Therefore, lowering cadmium accumulation in plants is highly desirable. Here, a rice cultivar 'Qisanzhan' was studied using differential display reverse transcription-polymerase chain reaction (DDRT-PCR). Fifty-six differentially expressed genes were found in the root tips of 4-leaf stage rice seedlings exposed to 4 and 12 h of 50 µmol/L Cd(NO3)2 in a nutrient solution using DDRT-PCR. Further validation using semi-quantitative RT-PCR showed that the expression patterns of 16 genes were consistent with those found in DDRT-PCR. These genes encode receptor-like protein kinase, pleiotropic drug resistance protein, aquaporin protein, plasma membrane ATPase, etc. The differentially genes identified here can be used to obtain a better understanding of the molecular mechanisms of Cd absorption and accumulation in plants.


Asunto(s)
Cadmio/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Estrés Fisiológico/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Oryza/genética , Proteínas de Plantas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Plantones/efectos de los fármacos , Plantones/metabolismo , Estrés Fisiológico/genética
5.
Mol Biotechnol ; 63(3): 221-231, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33439452

RESUMEN

Gene fragment swapping and site-directed mutagenesis are commonly required in dissecting functions of gene domains. While there are many approaches for seamless fusion of different gene fragments, new methods are yet to be developed to offer higher efficiency, better simplicity, and more affordability. In this study, we showed that in most cases overlap-PCR was highly effective in creating site-directed mutagenesis, gene fragment deletion, and substitutions using RUS1 and RUS2 as example. While for cases where the overlap-PCR approach is not feasible due to complex secondary structure of gene fragments, a unique restriction site can be generated at the overlapped region of the primers through synonymous mutations. Then different gene fragments can be seamlessly fused through traditional restriction digestion and subsequent ligation. In conclusion, while the classical overlap-PCR is not feasible, the modified overlap-PCR approaches can provide effective and alternative ways to seamlessly fuse different gene fragments.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Fusión Artificial Génica/métodos , Sustitución de Aminoácidos , Arabidopsis/química , Proteínas de Arabidopsis/química , Enzimas de Restricción del ADN/metabolismo , ADN de Plantas/química , Mutagénesis Sitio-Dirigida , Conformación de Ácido Nucleico , Reacción en Cadena de la Polimerasa/métodos , Eliminación de Secuencia
6.
Nat Prod Res ; 34(3): 405-412, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30406671

RESUMEN

Neogenkwanine I (1), a new daphnane-type diterpene with 4,7-ether group, along with four known ones (2-5), were isolated from Daphne genkwa. The structure including absolute configurations of 1 was established on the basis of NMR, 13C-NMR and ECD calculations and CD exciton chirality analysis. 13C-NMR and ECD calculations of daphnane-type diterpenes were reported here for the first time. All of the diterpenes were screened for their cytotoxic activities against MCF-7 and Hep3B cell lines. The cytotoxicity structure- activity relationship of compounds was illustrated with the absence of ortho-ester group of daphnane-type diterpenes.


Asunto(s)
Antineoplásicos/aislamiento & purificación , Daphne/química , Diterpenos/aislamiento & purificación , Flores/química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Citotoxinas/aislamiento & purificación , Citotoxinas/farmacología , Diterpenos/química , Diterpenos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Teoría Cuántica , Estereoisomerismo , Relación Estructura-Actividad
7.
Artículo en Inglés | MEDLINE | ID: mdl-17167199

RESUMEN

The cDNA of Alocasia macrorrhiza lectin (aml, GenBank accession number: DQ340864) was cloned by RACE-PCR and its characteristics were predicted by various bioinformatics tools. GSPs (Gene Specific Primers) were designed according to the conserved regions of the genes encoded for lectins and similar proteins from the same family Araceae. Total RNAs were extracted from the tubers of A macrorrhiza by Qiagen RNeasy mini kit. The 3'- and 5'-RACE-PCRs were performed with the isolated total RNAs by SMART(TM)RACE cDNA amplification kit from BD Biosciences Clontech Company, respectively. The purified PCR products were ligated with pMD 18-T vector, and the confirmed clones were sequenced. The full-length cDNA of aml was obtained by combination of 3'- and 5'-end sequences, and was then confirmed by full-length 3'-RACE-PCR. The aml cDNA is 1 124 bp long. The deduced amino acid length of AML lectin is 270 aa. Its relative molecular weight is 29.7 kD. The results of homologous analysis showed a high similarity between AML and other mannose-binding lectins and similar proteins from Araceae family. Two typical B-lectin domains and three mannose- binding motifs were found in the sequence of AML. With all these taken together, it can be concluded that this newly cloned aml cDNA encodes for a mannose-binding lectin.


Asunto(s)
Alocasia/genética , ADN Complementario/genética , Lectinas de Plantas/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Biología Computacional , ADN Complementario/química , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Lectinas de Plantas/química , Lectinas de Plantas/clasificación , Estructura Secundaria de Proteína , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido
8.
Mol Plant ; 4(4): 759-70, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21511809

RESUMEN

Vitamin B6 (vitB6) serves as an essential cofactor for more than 140 enzymes. Pyridoxal 5'-phosphate (PLP), active cofactor form of vitB6, can be photolytically destroyed by trace amounts of ultraviolet-B (UV-B). How sun-exposed organisms cope with PLP photosensitivity and modulate vitB6 homeostasis is currently unknown. We previously reported on two Arabidopsis mutants, rus1 and rus2, that are hypersensitive to trace amounts of UV-B light. We performed mutagenesis screens for second-site suppressors of the rus mutant phenotype and identified mutations in the ASPARTATE AMINOTRANSFERASE2 (ASP2) gene. ASP2 encodes for cytosolic aspartate aminotransferase (AAT), a PLP-dependent enzyme that plays a key role in carbon and nitrogen metabolism. Genetic analyses have shown that specific amino acid substitutions in ASP2 override the phenotypes of rus1 and rus2 single mutants as well as rus1 rus2 double mutant. These substitutions, all shown to reside at specific positions in the PLP-binding pocket, resulted in no PLP binding. Additional asp2 mutants that abolish AAT enzymatic activity, but which alter amino acids outside of the PLP-binding pocket, fail to suppress the rus phenotype. Furthermore, exogenously adding vitB6 in growth media can rescue both rus1 and rus2. Our data suggest that AAT plays a role in vitB6 homeostasis in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/enzimología , Aspartato Aminotransferasas/genética , Supresión Genética , Vitamina B 6/metabolismo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Arabidopsis/efectos de la radiación , Proteínas de Arabidopsis/metabolismo , Aspartato Aminotransferasas/química , Aspartato Aminotransferasas/metabolismo , Datos de Secuencia Molecular , Alineación de Secuencia , Rayos Ultravioleta
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