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1.
J Exp Bot ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38812358

RESUMEN

Plants, being sessile organisms, constantly need to respond to environmental stresses, often leading to the accumulation of reactive oxygen species (ROS). While ROS can be harmful, they also act as messengers guiding plant growth and stress responses. Because chloroplasts are sensitive to environmental changes and are both a source and target of ROS during stress conditions, they are important in conveying environmental changes to the nucleus, where acclimation responses are coordinated to maintain organellar and overall cellular homeostasis. ANAC102 has previously been established as a regulator of ß-cyclocitral-mediated chloroplast-to-nucleus signaling, protecting plants against photooxidative stress. However, debates persist about where ANAC102 is located - in chloroplasts or in the nucleus. Our study, utilizing the genomic ANAC102 sequence driven by its native promoter, establishes ANAC102 primarily as a nuclear protein, lacking a complete N-terminal chloroplast-targeting peptide. Moreover, our research reveals the sensitivity of plants overexpressing ANAC102 to severe superoxide-induced chloroplast oxidative stress. Transcriptome analysis unraveled ANAC102's dual role in negatively and positively regulating genome-wide transcriptional responses to chloroplast oxidative stress. Through the integration of published data and our own study, we constructed a comprehensive transcriptional network, which suggests that ANAC102 exerts direct and indirect control over transcriptional responses through downstream transcription factor networks, providing deeper insights into the ANAC102-mediated regulatory landscape during oxidative stress.

2.
Appl Opt ; 63(2): 383-389, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38227232

RESUMEN

The three-dimensional (3D) measurement task of complex microstructures holds paramount significance in the domains of precision manufacturing and inspection. The calibration of the 3D system heavily determines the final reconstruction accuracy. The widely adopted system calibration method is phase-height mapping (PHM) and stereo vision (SV) based. The former can be applied directly to the calculation without considering the imaging model of the system, but it relies on highly precise and expensive translation stages or standard blocks. The latter's accuracy cannot be guaranteed because it is difficult to accurately calibrate the projector. In this paper, we establish an optically coupled microscopic fringe projection profilometry system that consists of a Scheimpflug pinhole projector and a super-low distortion bi-telecentric camera. We introduce a simplified 3D system calibration approach that combines phase modulation transfer and ray propagation. Our method enables the simultaneous calibration of the system, including the calibration of the projector, camera, and the phase to a 3D coordinates relationship, using only a 2D target. The calibrated projector's external parameters are used to obtain the target's complete poses, and then the direct mapping coefficients of the phase to the 3D coordinates can be obtained through the optical geometry structure and phase labels. Comparable experiments verify the feasibility of the proposed method.

3.
Appl Opt ; 62(19): 5085-5093, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37707210

RESUMEN

The telecentric camera has found extensive application in microscopy imaging due to its remarkable attributes of maintaining constant magnification and minimal distortion within its depth of field. In telecentric imaging technology, the accuracy of measurements frequently hinges upon the calibration precision of the telecentric camera. In real-world scenarios, the shallow depth of field characteristic of telecentric cameras often leads to out-of-focus targets during the capturing process, which in turn results in the inability to accurately extract pixel coordinates of feature points, making it difficult for optimization algorithms to converge to the optimal value. We propose a nonlinear optimization algorithm based on pixel coordinates of optimized feature points for bitelecentric cameras. Incorporating pixel coordinates into the optimization process yields the theoretically optimal solution based on bitelecentric camera model. The obtained pixel coordinates are used for second initial value estimation, followed by the optimization of all parameters. Compared to existing methods, the proposed approach significantly reduces reprojection errors under both blurry and clear target conditions. Experimental results demonstrate superior performance in processing blurry defocused images.

4.
Arch Med Sci ; 19(2): 518-522, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37034521

RESUMEN

Introduction: The aim of this study is to investigate the role of genetic variation and DNA methylation of PEAR1 rs12041331 in high on-treatment platelet reactivity (HPR) and recurrent ischemic stroke (RIS). Methods: Genotype, methylation, and mRNA of PEAR1 rs12041331 were detected in patients with cerebral ischemia, for the analysis of the effect of PEAR1 rs12041331 on HPR and RIS. Results: The major G allele of PEAR1 rs12041331 was associated with hypermethylation, which was associated with HPR. This link was not observed for RIS. Conclusions: The PEAR1 rs12041331 genetic polymorphism and DNA methylation may be among the genetic factors affecting HPR. The correlation between PEAR1 and RIS needs to be studied further.

5.
Cell Discov ; 9(1): 27, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36878905

RESUMEN

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that affects social interaction and behavior. Mutations in the gene encoding chromodomain helicase DNA-binding protein 8 (CHD8) lead to autism symptoms and macrocephaly by a haploinsufficiency mechanism. However, studies of small animal models showed inconsistent findings about the mechanisms for CHD8 deficiency-mediated autism symptoms and macrocephaly. Using the nonhuman primate as a model system, we found that CRISPR/Cas9-mediated CHD8 mutations in the embryos of cynomolgus monkeys led to increased gliogenesis to cause macrocephaly in cynomolgus monkeys. Disrupting CHD8 in the fetal monkey brain prior to gliogenesis increased the number of glial cells in newborn monkeys. Moreover, knocking down CHD8 via CRISPR/Cas9 in organotypic monkey brain slices from newborn monkeys also enhanced the proliferation of glial cells. Our findings suggest that gliogenesis is critical for brain size in primates and that abnormal gliogenesis may contribute to ASD.

6.
Proc Natl Acad Sci U S A ; 120(11): e2221308120, 2023 03 14.
Artículo en Inglés | MEDLINE | ID: mdl-36897975

RESUMEN

Aerobic reactions are essential to sustain plant growth and development. Impaired oxygen availability due to excessive water availability, e.g., during waterlogging or flooding, reduces plant productivity and survival. Consequently, plants monitor oxygen availability to adjust growth and metabolism accordingly. Despite the identification of central components in hypoxia adaptation in recent years, molecular pathways involved in the very early activation of low-oxygen responses are insufficiently understood. Here, we characterized three endoplasmic reticulum (ER)-anchored Arabidopsis ANAC transcription factors, namely ANAC013, ANAC016, and ANAC017, which bind to the promoters of a subset of hypoxia core genes (HCGs) and activate their expression. However, only ANAC013 translocates to the nucleus at the onset of hypoxia, i.e., after 1.5 h of stress. Upon hypoxia, nuclear ANAC013 associates with the promoters of multiple HCGs. Mechanistically, we identified residues in the transmembrane domain of ANAC013 to be essential for transcription factor release from the ER, and provide evidence that RHOMBOID-LIKE 2 (RBL2) protease mediates ANAC013 release under hypoxia. Release of ANAC013 by RBL2 also occurs upon mitochondrial dysfunction. Consistently, like ANAC013 knockdown lines, rbl knockout mutants exhibit impaired low-oxygen tolerance. Taken together, we uncovered an ER-localized ANAC013-RBL2 module, which is active during the initial phase of hypoxia to enable fast transcriptional reprogramming.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Serina Endopeptidasas , Factores de Transcripción , Humanos , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Retículo Endoplásmico/metabolismo , Fibrinógeno/metabolismo , Regulación de la Expresión Génica de las Plantas , Hipoxia/metabolismo , Oxígeno/metabolismo , Factores de Transcripción/metabolismo , Serina Endopeptidasas/metabolismo
7.
J Exp Bot ; 74(6): 1940-1956, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36651677

RESUMEN

Transcriptional networks are crucial to integrate various internal and external signals into optimal responses during plant growth and development. In Arabidopsis thaliana, primary root vasculature patterning and proliferation are controlled by a network centred around the basic Helix-Loop-Helix transcription factor complex, formed by TARGET OF MONOPTEROS 5 (TMO5) and LONESOME HIGHWAY (LHW), which control cell proliferation and division orientation by modulating the cytokinin response and other downstream factors. Despite recent progress, many aspects of the TMO5/LHW pathway are not fully understood. In particular, the upstream regulators of TMO5/LHW activity remain unknown. Here, using a forward genetics approach to identify new factors of the TMO5/LHW pathway, we discovered a novel function of the MYB-type transcription factor, MYB12. MYB12 physically interacts with TMO5 and dampens the TMO5/LHW-mediated induction of direct target gene expression, as well as the periclinal/radial cell divisions. The expression of MYB12 is activated by the cytokinin response, downstream of TMO5/LHW, resulting in a novel MYB12-mediated negative feedback loop that restricts TMO5/LHW activity, to ensure optimal cell proliferation rates during root vascular development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Meristema , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Raíces de Plantas/metabolismo , Retroalimentación , Transactivadores/genética , Regulación de la Expresión Génica de las Plantas , Arabidopsis/metabolismo , División Celular , Citocininas/metabolismo
8.
PLoS Biol ; 20(11): e3001853, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36395107

RESUMEN

The accurate construction of neural circuits requires the precise control of axon growth and guidance, which is regulated by multiple growth and guidance cues during early nervous system development. It is generally thought that the growth and guidance cues that control the major steps of axon development have been defined. Here, we describe cerebellin-1 (Cbln1) as a novel cue that controls diverse aspects of axon growth and guidance throughout the central nervous system (CNS) by experiments using mouse and chick embryos. Cbln1 has previously been shown to function in late neural development to influence synapse organization. Here, we find that Cbln1 has an essential role in early neural development. Cbln1 is expressed on the axons and growth cones of developing commissural neurons and functions in an autocrine manner to promote axon growth. Cbln1 is also expressed in intermediate target tissues and functions as an attractive guidance cue. We find that these functions of Cbln1 are mediated by neurexin-2 (Nrxn2), which functions as the Cbln1 receptor for axon growth and guidance. In addition to the developing spinal cord, we further show that Cbln1 functions in diverse parts of the CNS with major roles in cerebellar parallel fiber growth and retinal ganglion cell axon guidance. Despite the prevailing role of Cbln1 as a synaptic organizer, our study discovers a new and unexpected function for Cbln1 as a general axon growth and guidance cue throughout the nervous system.


Asunto(s)
Axones , Cerebelo , Embrión de Pollo , Animales , Ratones , Axones/metabolismo , Cerebelo/metabolismo , Médula Espinal/metabolismo , Neuronas/metabolismo , Proteínas del Tejido Nervioso/genética , Precursores de Proteínas/metabolismo
9.
Nat Plants ; 7(4): 500-513, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33846597

RESUMEN

Gene regulation is a dynamic process in which transcription factors (TFs) play an important role in controlling spatiotemporal gene expression. To enhance our global understanding of regulatory interactions in Arabidopsis thaliana, different regulatory input networks capturing complementary information about DNA motifs, open chromatin, TF-binding and expression-based regulatory interactions were combined using a supervised learning approach, resulting in an integrated gene regulatory network (iGRN) covering 1,491 TFs and 31,393 target genes (1.7 million interactions). This iGRN outperforms the different input networks to predict known regulatory interactions and has a similar performance to recover functional interactions compared to state-of-the-art experimental methods. The iGRN correctly inferred known functions for 681 TFs and predicted new gene functions for hundreds of unknown TFs. For regulators predicted to be involved in reactive oxygen species (ROS) stress regulation, we confirmed in total 75% of TFs with a function in ROS and/or physiological stress responses. This includes 13 ROS regulators, previously not connected to any ROS or stress function, that were experimentally validated in our ROS-specific phenotypic assays of loss- or gain-of-function lines. In conclusion, the presented iGRN offers a high-quality starting point to enhance our understanding of gene regulation in plants by integrating different experimental data types.


Asunto(s)
Arabidopsis/genética , Redes Reguladoras de Genes/genética , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Arabidopsis/metabolismo , Cromatina/metabolismo , Motivos de Nucleótidos , Proteínas de Plantas , Unión Proteica , Factores de Transcripción/metabolismo
10.
Clin Lab ; 66(9)2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32902208

RESUMEN

BACKGROUND: At present, the relationship between serum homocysteine and microalbuminuria (MAU) in systemic lupus erythematosus (SLE) patients is still unclear. Therefore, the aim of our study was to analyze the association between serum homocysteine and MAU in SLE patients. METHODS: The study analyzed 150 patients with SLE at Affiliated Hospital of Youjiang Medical University for Nationalities retrospectively, and we collected for clinical and laboratory data. RESULTS: We found a positive correlation between serum homocysteine and MAU in SLE patients (r = 0.430, p < 0.001). We found that serum homocysteine levels were increased in SLE patients with MAU positive compared to those who were MAU negative (p < 0.001). After adjusting for multiple confounding factors, we found that serum homocysteine maintained a positive correlation with MAU in patients with SLE in multivariate correlation analysis (p = 0.253, r = 0.002). The receiver operating characteristic (ROC) curve with an area under the curve of 0.730, and serum homocysteine had 72.2% sensitivity and 61.9% specificity with cutoff values 9.0 to identify the SLE patients with MAU positive. CONCLUSIONS: The current results found a correlation between serum homocysteine and MAU in SLE patients, suggesting that elevated serum homocysteine levels might be an adverse factor for SLE patients with kidney injury.


Asunto(s)
Lupus Eritematoso Sistémico , Albuminuria/diagnóstico , Homocisteína , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/diagnóstico , Curva ROC , Estudios Retrospectivos
11.
J Biol Chem ; 295(41): 14125-14139, 2020 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-32605923

RESUMEN

Autophagy has been shown to maintain neural system homeostasis during stroke. However, the molecular mechanisms underlying neuronal autophagy in ischemic stroke remain poorly understood. This study aims to investigate the regulatory mechanisms of the pathway consisting of MEG3 (maternally expressed gene 3), microRNA-378 (miR-378), and GRB2 (growth factor receptor-bound protein 2) in neuronal autophagy and neurological functional impairment in ischemic stroke. A mouse model of the middle cerebral artery occluded-induced ischemic stroke and an in vitro model of oxygen-glucose deprivation-induced neuronal injury were developed. To understand the role of the MEG3/miR-378/GRB2 axis in the neuronal regulation, the expression of proteins associated with autophagy in neurons was measured by Western blotting analysis, and neuron death was evaluated using a lactate dehydrogenase leakage rate test. First, it was found that the GRB2 gene, up-regulated in middle cerebral artery occluded-operated mice and oxygen-glucose deprivation-exposed neurons, was a target gene of miR-378. Next, miR-378 inhibited neuronal loss and neurological functional impairment in mice, as well as neuronal autophagy and neuronal death by silencing of GRB2. Confirmatory in vitro experiments showed that MEG3 could specifically bind to miR-378 and subsequently up-regulate the expression of GRB2, which in turn suppressed the activation of Akt/mTOR pathway. Taken together, these findings suggested that miR-378 might protect against neuronal autophagy and neurological functional impairment and proposed that a MEG3/miR-378/GRB2 regulatory axis contributed to better understanding of the pathophysiology of ischemic stroke.


Asunto(s)
Autofagia , Isquemia Encefálica/metabolismo , Proteína Adaptadora GRB2/metabolismo , MicroARNs/metabolismo , Neuronas/metabolismo , ARN Largo no Codificante/metabolismo , Transducción de Señal , Accidente Cerebrovascular/metabolismo , Animales , Isquemia Encefálica/genética , Isquemia Encefálica/patología , Modelos Animales de Enfermedad , Proteína Adaptadora GRB2/genética , Humanos , Ratones , Ratones Mutantes , MicroARNs/genética , Neuronas/patología , ARN Largo no Codificante/genética , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/patología
12.
Chem Commun (Camb) ; 56(49): 6680-6683, 2020 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-32412017

RESUMEN

A regio- and stereoselective iodolactonization of internal electron-deficient olefinic acids has been reported, which provides a straightforward access to a series of multi-functionalized seven-membered lactones containing two consecutive chiral centers. The ester substituents on the olefins played a key role in achieving high regioselectivity. This result was proved through experiments and DFT calculations.

13.
Org Lett ; 22(11): 4129-4134, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32459099

RESUMEN

Biphenylcarboxylic acid with two competing C(sp2)-H sites was designed for site selective C(sp2)-H functionalization by developing carboxylic acids assisted remote and selective olefination via 7-membered palladacycle. Mechanism investigation and DFT calculations reveal a kinetics-determined process, which could be utilized to explore a variety of remote site selectivity. The practicability of this method was highlighted by the precise construction of phenathrene under sequential site selectivity.

14.
Org Lett ; 22(4): 1331-1335, 2020 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-32009417

RESUMEN

Ru(II)-catalyzed direct alkylation of tertiary phosphines via hydroarylation of activated olefins promoted by mono-N-protected amino acid (MPAA) was achieved. This protocol provides a straightforward access to a large library of Buchwald-type bulky alkylated monophosphines from commercially available biaryl phosphine. Moreover, two ruthenacycle intermediates of tertiary phosphines via C-H bond cleavage were isolated to illustrate the mechanism of P(III)-directed C-H activation.

15.
Inorg Chem ; 58(23): 16171-16179, 2019 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-31718168

RESUMEN

The active lone pair electron effect and highly flexible coordination geometry of Pb2+ prevented the rational construction of metal-organic frameworks (MOFs) but promoted excellent fluorescence tuning. The regulation on organic and alkali templates facilitated the assemblies of three new Pb-MOFs: [Pb2(pia)2(DMA)]·DMA (1), [Pb2(pia)2(DMF)]·1.5DMF (2), and [Pb2(pia)2(DMF)]·NEt3 (3). They were rigid rod-spacer and double-walls frameworks, which possess defective dicubane [Pb4O6] based metal-carboxyl chains constructed from both semidirected and holodirected Pb2+ ions. These MOFs exhibited thermal stability up to 370 °C and unprecedented chemical stability in H2O and acidic (pH 2) and alkaline (pH 12) aqueous solutions, found for the first time in Pb-MOFs. A single-phase and rare-earth-free white-emitting phosphor, 1, was screen out, which showed a near-sunlight and human-vision-friendly broadband spectrum covering the full visible region, possessing the close-to-pure-white chromaticity coordinates of (0.332, 0.347), a near-daylight color temperature of 5696 K, and a high color rendering index of 95. The replacement of DMF as apical ligand and guest in 2 resulted in an intrinsic single and narrow emission at 562 nm with yellow color. The convenient yellow-and-blue color-tuning until white for 2 was realized by either solution or solid blending with blue-emissive H2pia, benefited from their highly matched excitation spectra. Using large NEt3 as template guest induced great framework distortion for 3 and led to white emission with chromaticity coordinates of (0.302, 0.294), stemming from nonequivalent dual emission at 450 and 545 nm. In-depth structure analysis revealed intra-/interchain Pb···Pb interactions in the lead(II)-carboxyl chains greatly affected the photochemical output.

16.
Org Lett ; 21(8): 2885-2889, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30957500

RESUMEN

A general protocol for site-preferential mono-C-H arylation of tertiary phosphine ligands catalyzed by a ruthenium(II) complex was devised. This protocol gives access to a series of modified Buchwald-biaryl monophosphines on a gram scale in moderate to excellent yields. A catalytic cycle is proposed derived from knowledge of the intermediates observed by ESI-MS. Importantly, these monoarylated products could be further transformed into dibenzophosphole derivatives.

17.
Org Lett ; 20(22): 7274-7277, 2018 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-30388016

RESUMEN

A weakly carboxylate-directed palladium(II)-catalyzed ortho-C-H alkynylation of diverse phenylacetic acids promoted by monoprotected amino acid ligand enabled is reported. The reaction has a broad substrate scope including α-secondary, tertiary, and quaternary phenylacetic acids. Notably, the direct ortho-C-H alkynylation of α-quaternary phenylacetic acids and chiral α-tertiary phenylacetic acids was achieved for the first time. Moreover, this method could be used for simple and efficient gram-scale synthesis and diversification of an anti-inflammatory drug.

18.
J Neurochem ; 141(3): 373-386, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28160291

RESUMEN

Adding a free radical-scavenging nitrone moiety on tetramethylpyrazine, we have previously synthesized a chemical named 2-[[(1,1-dimethylethyl)oxidoimino]-methyl]-3,5,6-trimethylpyrazine (tetramethylpyrazine nitrone, or TBN) and proved its neuroprotective effect but with limited understanding of its mechanism. Here we ask if TBN protects retinal ganglion cells (RGCs) against excitotoxicity induced by NMDA and explore the underlying mechanism. NMDA was intravitreally injected to induce RGC injury in rats, followed by daily intraperitoneal administrations of TBN. Measurements of TBN concentration at different times after intraperitoneal administration showed that more than 200 µM TBN reached the aqueous humor quickly. Then RGCs' survival was evaluated by quantifying Brn3-positive cells, and retinal functions were examined by electroretinogram and visual behaviors. TBN significantly increased the survival of RGCs after NMDA insult, recovered the amplitude of photopic negative responses to flash, and restored the visual behavior. Furthermore, TBN inhibited the apoptotic process, as indicated by the elevated ratios of cleaved caspase-3/caspase-3 and of Bax/Bcl-2, and decreased the level of reactive oxygen species. Moreover, TBN reduced RGC's calcium overload induced by NMDA or by KCl. Whole-cell patch recording from RGCs further showed that TBN slightly but significantly inhibited L-type calcium channels, but had little effect on T-type calcium channel or NMDA-, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid(AMPA)-induced current. Thus our data indicate that TBN alleviates NMDA-elicited injury of rat RGCs both morphologically and functionally, possibly by inhibiting the L-type calcium channel thus reducing Ca2+ overload and by directly scavenging free radicals. Therefore, TBN may be a novel candidate for treating excitotoxicity-related visual disorders such as glaucoma.


Asunto(s)
Agonistas de Aminoácidos Excitadores/toxicidad , N-Metilaspartato/antagonistas & inhibidores , N-Metilaspartato/toxicidad , Fármacos Neuroprotectores/farmacología , Pirazinas/farmacología , Células Ganglionares de la Retina/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio Tipo L/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Electrorretinografía , Femenino , Inyecciones , Estimulación Luminosa , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/metabolismo , Visión Ocular/efectos de los fármacos , Cuerpo Vítreo
19.
Plant Physiol Biochem ; 109: 387-396, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27814568

RESUMEN

Tartary buckwheat is a strongly abiotic, resistant coarse cereal, but its tolerance mechanisms for stress are largely unknown. MYB transcription factors play key roles in various physiological, biochemical and molecular responses, which can both positively and negatively regulate the stress tolerance of plants. In this study, we report that the expression of FtMYB10, a R2R3-MYB gene from Tartary buckwheat, was induced significantly by ABA and drought treatments. A seed germination test under ABA treatment indicated that transgenic lines were less sensitive to ABA. The overexpression of FtMYB10 in Arabidopsis reduced drought and salt tolerance. Further studies showed that the proline contents in the transgenic plants are markedly decreased associated with reduced expression of the P5CS1 gene under both normal and stress conditions. Furthermore, the expression of some stress-responsive genes, including DREB1/CBFs, RD29B, RD22, and several genes of the DRE/CRT class, decreased in response to FtMYB10 overexpression in Arabidopsis. These results suggest that FtMYB10 may play a key role in ABA signaling feedback regulation and act as a novel negative regulator of salt and drought stress tolerance in plants.


Asunto(s)
Fagopyrum/genética , Fagopyrum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Ácido Abscísico/farmacología , Aclimatación/genética , Secuencia de Aminoácidos , Arabidopsis/genética , Arabidopsis/metabolismo , Sequías , Fagopyrum/efectos de los fármacos , Expresión Génica , Genes de Plantas , Filogenia , Plantas Modificadas Genéticamente , Tolerancia a la Sal/genética , Homología de Secuencia de Aminoácido , Estrés Fisiológico
20.
J Agric Food Chem ; 64(37): 6930-8, 2016 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-27571449

RESUMEN

Anthocyanins confer the red color in the hypocotyl of tartary buckwheat sprouts. Uridine diphosphate (UDP)-glucose:flavonoid 3-O-glycosyltransferase (UFGT) stabilizes anthocyanin by attaching the glucosyl moiety from UDP-glucose to the C3 hydroxyl of anthocyanin. In this study, we characterized three UFGT-like genes, designated FtUFGT1, 2, and 3 from tartary buckwheat. The results revealed that FtUFGT1, FtUFGT2, and FtUFGT3 can convert cyanidin to cyanidin 3-O-glucoside, with specific activities of 20.01 × 10(-3), 8.93 × 10(-3), and 20.24 × 10(-3) IU/mg, respectively. The active-site residues of the C-terminal domains and the N-terminal domains are important for the donor and acceptor recognition of these proteins. The expression of the three FtUFGTs paralleled the tissue-specific anthocyanin accumulation. After cold treatment, the increased content of anthocyanin was accompanied by the up-regulated expression of the three FtUFGTs. Among these three UGFT gene members, FtUFGT3 showed the highest expression level and the highest specific activity, suggesting that FtUFGT3 might be the major gene involved in anthocyanin biosynthesis. These results suggested that the FtUFGT genes, FtUFGT3 in particular, might be important candidates for anthocyanin formation in tartary buckwheat sprouts.


Asunto(s)
Fagopyrum/enzimología , Glucosiltransferasas/genética , Proteínas de Plantas/genética , Antocianinas/metabolismo , Frío , Fagopyrum/genética , Fagopyrum/crecimiento & desarrollo , Fagopyrum/metabolismo , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/metabolismo , Proteínas de Plantas/metabolismo , Semillas/enzimología , Semillas/genética , Semillas/crecimiento & desarrollo , Semillas/metabolismo , Estrés Fisiológico
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