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1.
BMC Health Serv Res ; 24(1): 400, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553762

RESUMO

BACKGROUND: Forensic psychiatry is often associated with long admissions and has a high cost of care. There is little known about factors influencing length of stay (LOS), and no previous systematic review has synthesised the available data. This paper aims to identify factors influencing the LOS in forensic psychiatry hospitals to inform care and interventions that may reduce the length of admissions. METHODOLOGY: A systematic review was conducted by searching major databases, including PubMed, EMBASE and PsycInfo, from inception until May 2022. Observational studies conducted in forensic hospitals that examined associations between variables of interest and LOS were included. Following data extraction, the Newcastle‒Ottawa Scale was used for quality appraisal. No meta-analysis was conducted due to heterogeneity of information; a quantitative measure to assess the strength of evidence was developed and reported. RESULTS: A total of 28 studies met the inclusion criteria out of 1606 citations. A detailed quantitative synthesis was performed using robust criteria. Having committed homicide/attempted homicide, a criminal legal status with restrictions, and a diagnosis of schizophrenia-spectrum disorders were all associated with longer LOS. Higher Global Assessment of Functioning (GAF) scores were associated with a shorter LOS. CONCLUSION: High-quality research examining factors associated with LOS in forensic psychiatry is lacking, and studies are heterogeneous. No modifiable characteristics were identified, and thus, practice recommendations were not made. There is an increasing necessity to understand the factors associated with longer admissions to inform care and increase success in reintegration and rehabilitation. This paper provides recommendations for future research.

3.
MMWR Morb Mortal Wkly Rep ; 72(36): 973-978, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37676839

RESUMO

Eight cases of locally acquired, mosquito-transmitted (i.e., autochthonous) Plasmodium vivax malaria, which has not been reported in the United States since 2003, were reported to CDC from state health departments in Florida and Texas during May 18-July 17, 2023. As of August 4, 2023, case surveillance, mosquito surveillance and control activities, and public outreach and education activities continue in both states. U.S. clinicians need to consider a malaria diagnosis in patients with unexplained fever, especially in areas where autochthonous malaria has been recently reported, although the risk for autochthonous malaria in the United States remains very low. Prompt diagnosis and treatment of malaria can prevent severe disease or death and limit ongoing transmission to local Anopheles mosquitoes and other persons. Preventing mosquito bites and controlling mosquitoes at home can prevent mosquitoborne diseases, including malaria. Before traveling internationally to areas with endemic malaria, travelers should consult with a health care provider regarding recommended malaria prevention measures, including potentially taking malaria prophylaxis. Malaria is a nationally notifiable disease; continued reporting of malaria cases to jurisdictional health departments and CDC will also help ensure robust surveillance to detect and prevent autochthonous malaria in the United States.


Assuntos
Surtos de Doenças , Malária , Animais , Humanos , Texas/epidemiologia , Florida/epidemiologia , Malária/epidemiologia , Malária/prevenção & controle , Pessoal de Saúde
4.
Medicina (Kaunas) ; 59(7)2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37512030

RESUMO

Inflammatory bowel disease (IBD) is an illness with increasing prevalence, particularly in emerging countries, which can have a substantial impact on the quality of life of the patient. The illness is rather heterogeneous with different evolution among patients. A machine learning approach is followed in this paper to identify potential genes that are related to IBD. This is done by following a Monte Carlo simulation approach. In total, 23 different machine learning techniques were tested (in addition to a base level obtained using artificial neural networks). The best model identified 74 genes selected by the algorithm as being potentially involved in IBD. IBD seems to be a polygenic illness, in which environmental factors might play an important role. Following a machine learning approach, it was possible to obtain a classification accuracy of 84.2% differentiating between patients with IBD and control cases in a large cohort of 2490 total cases. The sensitivity and specificity of the model were 82.6% and 84.4%, respectively. It was also possible to distinguish between the two main types of IBD: (1) Crohn's disease and (2) ulcerative colitis.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Qualidade de Vida , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/epidemiologia , Doença de Crohn/diagnóstico , Doença de Crohn/genética , Colite Ulcerativa/genética , Aprendizado de Máquina
5.
Teach Psychol ; 50(3): 264-277, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37337592

RESUMO

Background: The COVID-19 pandemic resulted in an abrupt transition from in-person to online learning in Spring 2020. Objective: The purpose of this study was to identify the impact of the transition on undergraduates during the period following the campus closure. Method: 131 psychology undergraduate students completed an online survey of how the COVID-19 closure had impacted their academics, online learning environment, and traumatic stress symptoms (using the Posttraumatic Stress Disorder Checklist for the DSM-5). Results: Most participants reported increased academic difficulty compared to before closure. Approximately 30% reported elevated traumatic stress symptoms. Greater traumatic stress was associated with greater difficulty completing assignments, more limited access to the internet and quiet places to study, and greater sibling-care responsibilities. Conclusions: The acute transition to online instruction posed academic and emotional challenges to many students, especially those from environments with competing demands or less access to academic supports. Follow-up evaluation is needed to determine whether these difficulties have persisted in subsequent semesters of online instruction. Teaching Implication: Instructors should anticipate the emotional and academic needs of students who are relatively unfamiliar with online instruction and consider ways to minimize negative environmental impacts and increase access to mental health resources.

6.
Microorganisms ; 11(2)2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36838206

RESUMO

Mounting a balanced and robust humoral immune response is of utmost importance for reducing the infectivity of Trypanosoma cruzi. While the role of such a response in controlling the infection is well known, there is a lack of tools that can be used to quickly evaluate it. We developed a serum parasite inhibition assay (to evaluate changes in the parasite infection after exposing infective T. cruzi trypomastigotes to serum samples from infected patients). It is based on Vero cells as the hosts and the Tulahuen ß-galactosidase parasite strain, genetically engineered to be quantifiable by spectrophotometry. In parallel, we developed an in-house ELISA to correlate the anti-T. cruzi antibody titres of the clinical samples with their observed anti-parasitic effect in the serum parasite inhibition assay. Serum samples from chronically T. cruzi-infected patients significantly inhibited parasite invasion in a titre-dependant manner, regardless of the patient's clinical status, compared to samples from the non-infected controls. In addition, there was a clear correlation between the reactivity of the samples to the whole-parasite lysates by ELISA and the inhibitory effect. The results of this work confirm the previously described anti-parasitic effect of the serum of individuals exposed to T. cruzi and present a framework for its large-scale evaluation in further studies. The serum parasite inhibition assay represents a reproducible way to evaluate the intensity and anti-parasitic effect of humoral responses against T. cruzi, which could be applied to the evaluation of candidate antigens/epitopes in the design of Chagas disease vaccine candidates.

7.
Gene ; 855: 147131, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539044

RESUMO

Staphylococcus aureus is the main etiological agent of mastitis in small ruminants worldwide. This disease has a difficult cure and possible relapse, leading to significant economic losses in production, milk quality and livestock. This study performed comparative genomic analyses between 73 S. aureus genomes from different hosts (human, bovine, pig and others). This work isolated and sequenced 12 of these genomes from ovine. This study contributes to the knowledge of genomic specialization and the role of specific genes in establishing infection in ovine mastitis-associated S. aureus. The genomes of S. aureus isolated from sheep maintained a higher representation when grouped with clonal complexes 130 and 133. The genomes showed high genetic similarity, the species pan-genome consisting of 4200 genes (central = 2008, accessory = 1559 and unique = 634). Among these, 277 unique genes were related to the genomes isolated from sheep, with 39.6 % as hypothetical proteins, 6.4 % as phages, 6.4 % as toxins, 2.9 % as transporters, and 44.7 % as related to other proteins. Furthermore, at the pathogen level, they showed 80 genes associated with virulence factors and 19 with antibiotic resistance shared in almost all isolates. Although S. aureus isolated from ovine showed susceptibility to antimicrobials in vitro, ten genes were predicted to be associated with antibiotic inactivation and efflux pump, suggesting resistance to gentamicin and penicillin. This work may contribute to identifying genes acquired by horizontal transfer and their role in host adaptation, virulence, bacterial resistance, and characterization of strains affecting ovine.


Assuntos
Mastite Bovina , Infecções Estafilocócicas , Feminino , Animais , Bovinos , Ovinos/genética , Humanos , Suínos , Fatores de Virulência/genética , Staphylococcus aureus/genética , Adaptação ao Hospedeiro , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/veterinária , Infecções Estafilocócicas/microbiologia , Ruminantes/genética , Genômica , Sequências Repetitivas Dispersas , Mastite Bovina/genética , Mastite Bovina/microbiologia
8.
Int J Mol Sci ; 23(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35806053

RESUMO

Twenty-six triazole-based derivatives were designed for targeting both PD-L1 (programmed death receptor ligand 1) and VEGFR-2 (vascular endothelial growth factor receptor 2). These compounds were synthetized and biologically evaluated as multitarget inhibitors of VEGFR-2, PD-L1 and c-Myc proteins. The antiproliferative activity of these molecules on several tumor cell lines (HT-29, A-549, and MCF-7) and on the non-tumor cell line HEK-293 was determined. The effects on the abovementioned biological targets were evaluated for some selected compounds. Compound 23, bearing a p-chlorophenyl group, showed better results than sorafenib in regard to the downregulation of VEGFR-2 and a similar effect to BMS-8 on both PD-L1 and c-Myc proteins. The antiangiogenic and antivascular activities of chloro derivatives were also established by endothelial microtube formation assay on Matrigel®.


Assuntos
Antineoplásicos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Antígeno B7-H1 , Linhagem Celular Tumoral , Proliferação de Células , Ensaios de Seleção de Medicamentos Antitumorais , Células HEK293 , Humanos , Simulação de Acoplamento Molecular , Proteínas Proto-Oncogênicas c-myc/metabolismo , Relação Estrutura-Atividade , Triazóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
9.
Org Biomol Chem ; 19(47): 10424-10431, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34825690

RESUMO

Here, we combine the use of host screening, protein crystallography and QM/MM molecular dynamics simulations to investigate how the protein structure affects iminium catalysis by biotinylated secondary amines in a model 1,4 conjugate addition reaction. Monomeric streptavidin (M-Sav) lacks a quaternary structure and the solvent-exposed reaction site resulted in poor product conversion in the model reaction with low enantio- and regioselectivities. These parameters were much improved when the tetrameric host T-Sav was used; indeed, residues at the symmetrical subunit interface were proven to be critical for catalysis through a mutagenesis study. The use of QM/MM simulations and the asymmetric dimeric variant D-Sav revealed that both Lys121 residues which are located in the hosting and neighboring subunits play a critical role in controlling the stereoselectivity and reactivity. Lastly, the D-Sav template, though providing a lower conversion than that of the symmetric tetrameric counterpart, is likely a better starting point for future protein engineering because each surrounding residue within the asymmetric scaffold can be refined for secondary amine catalysis.


Assuntos
Estreptavidina
10.
Adv Appl Bioinform Chem ; 14: 25-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33623396

RESUMO

Neglected tropical diseases are infectious diseases that impose high morbidity and mortality rates over 1.5 billion people worldwide. Originally restricted to tropical and subtropical regions, changing climate conditions have increased their potential to emerge elsewhere. Control of their impact suffers from shortages like poor epidemiological surveillance or irregular drug distribution, and some NTDs still lack of appropriate diagnostics and/or efficient therapeutics. For these, availability of vaccines to prevent new infections, or the worsening of those already established, would mean a major breakthrough. However, only dengue and rabies count with approved vaccines at present. Herein, we review the state-of-the-art of vaccination strategies for NTDs, setting the focus on third generation vaccines and the concept of reverse vaccinology. Its capability to address pathogens´ biological complexity, likely contributing to save developmental costs is discussed. The use of computational tools is a fundamental aid to analyze increasingly large datasets aimed at designing vaccine candidates with the highest, possibly, opportunities to succeed. Ultimately, we identify and analyze those studies that took an in silico approach to find vaccine candidates, and experimentally assessed their immunogenicity and/or protection capabilities.

11.
Sci Rep ; 10(1): 552, 2020 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953512

RESUMO

Colored apocarotenoids accumulate at high concentrations in few plant species, where display a role in attraction of pollinators and seed dispersers. Among these apocarotenoids, crocins accumulate at high concentrations in the stigma of saffron and are responsible for the organoleptic and medicinal properties of this spice. Phytoene synthase and Orange protein are key for carotenoid biosynthesis and accumulation. We previously isolated four phytoene synthase genes from saffron with differential roles in carotenoid and apocarotenoid biosynthesis. However, the implications of Orange genes in the regulation of apocarotenoid accumulation are unknown. Here, we have identified two Orange genes from saffron, with different expression patterns. CsOr-a was mainly expressed in vegetative tissues and was induced by light and repressed by heat stress. Both CsOr-a and CsOr-b were expressed in stigmas but showed a different profile during the development of this tissue. The interactions of CsOr-a and CsOr-b were tested with all the four phytoene synthase proteins from saffron and with CsCCD2. None interactions were detected with CCD2 neither with the phytoene synthase 2, involved in apocarotenoid biosynthesis in saffron. The obtained results provide evidence of different mechanisms regulating the phytoene synthase enzymes in saffron by Orange for carotenoid and apocarotenoid accumulation in saffron.


Assuntos
Crocus/crescimento & desenvolvimento , Geranil-Geranildifosfato Geranil-Geraniltransferase/metabolismo , Proteínas de Choque Térmico HSP40/genética , Proteínas de Choque Térmico HSP40/metabolismo , Carotenoides/metabolismo , Crocus/genética , Crocus/metabolismo , Regulação da Expressão Gênica de Plantas , Resposta ao Choque Térmico , Luz , Especificidade de Órgãos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
12.
J Clin Med ; 8(10)2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31561432

RESUMO

Type 2 diabetes mellitus represents 30-50% of the cases of end stage renal disease worldwide. Thus, a correct evaluation of renal function in patients with diabetes is crucial to prevent or ameliorate diabetes-associated kidney disease. The reliability of formulas to estimate renal function is still unclear, in particular, those new equations based on cystatin-C or the combination of creatinine and cystatin-C. We aimed to assess the error of the available formulas to estimate glomerular filtration rate in diabetic patients. We evaluated the error of creatinine and/or cystatin-C based formulas in reflecting real renal function over a wide range of glomerular filtration rate (from advanced chronic kidney disease to hyperfiltration). The error of estimated glomerular filtration rate by any equation was common and wide averaging 30% of real renal function, and larger in patients with measured glomerular filtration rate below 60 mL/min. This led to chronic kidney disease stages misclassification in about 30% of the individuals and failed to detect 25% of the cases with hyperfiltration. Cystatin-C based formulas did not outperform creatinine based equations, and the reliability of more modern algorithms proved to be as poor as older equations. Formulas failed in reflecting renal function in type 2 diabetes mellitus. Caution is needed with the use of these formulas in patients with diabetes, a population at high risk for kidney disease. Whenever possible, the use of a gold standard method to measure renal function is recommended.

13.
BMC Genomics ; 20(1): 320, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-31029081

RESUMO

BACKGROUND: Crocins are soluble apocarotenoids that mainly accumulate in the stigma tissue of Crocus sativus and provide the characteristic red color to saffron spice, in addition to being responsible for many of the medicinal properties of saffron. Crocin biosynthesis and accumulation in saffron is developmentally controlled, and the concentration of crocins increases as the stigma develops. Until now, little has been known about the molecular mechanisms governing crocin biosynthesis and accumulation. This study aimed to identify the first set of gene regulatory processes implicated in apocarotenoid biosynthesis and accumulation. RESULTS: A large-scale crocin-mediated RNA-seq analysis was performed on saffron and two other Crocus species at two early developmental stages coincident with the initiation of crocin biosynthesis and accumulation. Pairwise comparison of unigene abundance among the samples identified potential regulatory transcription factors (TFs) involved in crocin biosynthesis and accumulation. We found a total of 131 (up- and downregulated) TFs representing a broad range of TF families in the analyzed transcriptomes; by comparison with the transcriptomes from the same developmental stages from other Crocus species, a total of 11 TF were selected as candidate regulators controlling crocin biosynthesis and accumulation. CONCLUSIONS: Our study generated gene expression profiles of stigmas at two key developmental stages for apocarotenoid accumulation in three different Crocus species. Differential gene expression analyses allowed the identification of transcription factors that provide evidence of environmental and developmental control of the apocarotenoid biosynthetic pathway at the molecular level.


Assuntos
Carotenoides/biossíntese , Crocus/genética , Regulação da Expressão Gênica de Plantas , Carotenoides/análise , Cromatografia Líquida de Alta Pressão , Dioxigenases/genética , Dioxigenases/metabolismo , Perfilação da Expressão Gênica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plastídeos/genética , Plastídeos/metabolismo , RNA de Plantas/química , RNA de Plantas/metabolismo , Análise de Sequência de RNA , Espectrometria de Massas por Ionização por Electrospray , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Front Plant Sci ; 10: 249, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30886624

RESUMO

Crocus sativus stigmas are the main source of crocins, which are glucosylated apocarotenoids derived from zeaxanthin cleavage that give saffron its red color. Phytoene synthase (PSY) mediates the first committed step in carotenoid biosynthesis in plants. Four PSY genes encoding functional enzymes were isolated from saffron. All the proteins were localized in plastids, but the expression patterns of each gene, CsPSY1a, CsPSY1b, CsPSY2, and CsPSY3, in different saffron tissues and during the development of the stigma showed different tissue specialization. The CsPSY2 transcript was primarily detected in the stigmas where it activates and stimulates the accumulation of crocins, while its expression was very low in other tissues. In contrast, CsPSY1a and CsPSY1b were mainly expressed in the leaves, but only CsPSY1b showed stress-light regulation. Interestingly, CsPSY1b showed differential expression of two alternative splice variants, which differ in the intron retention at their 5' UTRs, resulting in a reduction in their expression levels. In addition, the CsPSY1a and CsPSY1b transcripts, together with the CsPSY3 transcript, were induced in roots under different stress conditions. The CsPSY3 expression was high in the root tip, and its expression was associated with mycorrhizal colonization and strigolactone production. CsPSY3 formed a separate branch to the stress-specific Poaceae homologs but was closely related to the dicot PSY3 enzymes.

15.
Phys Chem Chem Phys ; 20(40): 25722-25737, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30280169

RESUMO

The origin of the catalytic power of enzymes has been a question of debate for a long time. In this regard, the possible contribution of protein dynamics in enzymatic catalysis has become one of the most controversial topics. In the present work, the hydride transfer step in the formate dehydrogenase (FDH EC 1.2.1.2) enzyme is studied by means of molecular dynamic (MD) simulations with quantum mechanics/molecular mechanics (QM/MM) potentials in order to explore any correlation between dynamics, tunnelling effects and the rate constant. The temperature dependence of the kinetic isotope effects (KIEs), which is one of the few tests that can be studied by experiments and simulations to shed light on this debate, has been computed and the results have been compared with previous experimental data. The classical mechanical free energy barrier and the number of recrossing trajectories seem to be temperature-independent while the quantum vibrational corrections and the tunnelling effects are slightly temperature-dependent over the interval of 5-45 °C. The computed primary KIEs are in very good agreement with previous experimental data, being almost temperature-independent within the standard deviations. The modest dependence on the temperature is due to just the quantum vibrational correction contribution. These results, together with the analysis of the evolution of the collective variables such as the electrostatic potential or the electric field created by the protein on the key atoms involved in the reaction, confirm that while the protein is well preorganised, some changes take place along the reaction that favour the hydride transfer and the product release. Coordinates defining these movements are, in fact, part of the real reaction coordinate.


Assuntos
Formiato Desidrogenases/metabolismo , Isótopos/química , Temperatura , Formiato Desidrogenases/química , Cinética
16.
PLoS One ; 13(9): e0203308, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30256802

RESUMO

This study examined the sexual reproductive cycle, energy storage and metabolic requirements of a Mediterranean gorgonian in a mesophotic ecosystem (~70 m depth). Paramuricea macrospina resulted to be a gonochoric internal brooding species with a 1:1 population sex ratio. Oogenesis lasted ~12-14 months, whereas spermatogenesis was significantly shorter, only lasting 6 months. Fertilization occurred during late summer (August) and larval release occurred during autumn (September-October). The organic matter and total lipid content showed a slight seasonal variability. Stable isotopic composition remained constant throughout the year, reflecting a general stability in gorgonian food sources. Conversely, the free fatty acid composition varied seasonally, reflecting changes in P. macrospina energetic demands probably related to gametogenesis and larval brooding. The reproductive ecology and biochemical composition of P. macrospina significantly differ from shallow coastal gorgonian species, reflecting the higher environmental stability of deeper environments.


Assuntos
Antozoários/fisiologia , Animais , Antozoários/crescimento & desenvolvimento , Recifes de Corais , Ecossistema , Metabolismo Energético , Ácidos Graxos não Esterificados/metabolismo , Feminino , Metabolismo dos Lipídeos , Masculino , Mar Mediterrâneo , Oogênese , Reprodução/fisiologia , Estações do Ano , Espanha , Espermatogênese
17.
Angew Chem Int Ed Engl ; 57(38): 12478-12482, 2018 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-30027571

RESUMO

There has been growing interest in performing organocatalysis within a supramolecular system as a means of controlling reaction reactivity and stereoselectivity. Here, a protein is used as a host for iminium catalysis. A pyrrolidine moiety is covalently linked to biotin and introduced to the protein host streptavidin for organocatalytic activity. Whereas in traditional systems stereoselectivity is largely controlled by the substituents added to the organocatalyst, enantiomeric enrichment by the reported supramolecular system is completely controlled by the host. Also, the yield of the model reaction increases over 10-fold when streptavidin is included. A 1.1 Šcrystal structure of the protein-catalyst complex and molecular simulations of a key intermediate reveal the chiral scaffold surrounding the organocatalytic reaction site. This work illustrates that proteins can be an excellent supramolecular host for driving stereoselective secondary amine organocatalysis.


Assuntos
Iminas/química , Estreptavidina/química , Sítios de Ligação , Biotina/química , Biotina/metabolismo , Biotinilação , Catálise , Cromatografia Gasosa-Espectrometria de Massas , Ligação de Hidrogênio , Conformação Molecular , Simulação de Dinâmica Molecular , Estereoisomerismo , Estreptavidina/metabolismo
18.
PLoS One ; 11(12): e0168736, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28030614

RESUMO

Using a subtractive hybridization approach, differentially expressed genes involved in the light response in saffron stigmas were identified. Twenty-two differentially expressed transcript-derived fragments were cloned and sequenced. Two of them were highly induced by light and had sequence similarity to early inducible proteins (ELIP) and SOUL heme-binding proteins. Using these sequences, we searched for other family members expressed in saffron stigma. ELIP and SOUL are represented by small gene families in saffron, with four and five members, respectively. The expression of these genes was analyzed during the development of the stigma and in light and dark conditions. ELIP transcripts were detected in all the developmental stages showing much higher expression levels in the developed stigmas of saffron and all were up-regulated by light but at different levels. By contrast, only one SOUL gene was up-regulated by light and was highly expressed in the stigma at anthesis. Both the ELIP and SOUL genes induced by light in saffron stigmas might be associated with the structural changes affecting the chromoplast of the stigma, as a result of light exposure, which promotes the development and increases the number of plastoglobules, specialized in the recruitment of specific proteins, which enables them to act in metabolite synthesis and disposal under changing environmental conditions and developmental stages.


Assuntos
Crocus/crescimento & desenvolvimento , Crocus/genética , Flores/crescimento & desenvolvimento , Flores/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Plantas/genética , Técnicas de Hibridização Subtrativa , Sequência de Aminoácidos , Clonagem Molecular , Crocus/efeitos da radiação , Flores/efeitos da radiação , Regulação da Expressão Gênica no Desenvolvimento/efeitos da radiação , Luz , Filogenia , Proteínas de Plantas/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Plant Mol Biol ; 91(3): 355-74, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27071403

RESUMO

The carotenoid cleavage dioxygenase 2, a new member of the CCD family, catalyzes the conversion of zeaxanthin into crocetin-dialdehyde in Crocus. CCD2 is expressed in flowers, being responsible for the yellow, orange and red colorations displayed by tepals and stigma. Three CsCCD2 genes were identified in Crocus sativus, the longest contains ten exons and the shorter is a truncated copy with no introns and which lacks one exon sequence. Analysis of RNA-seq datasets of three developmental stages of saffron stigma allowed the determination of alternative splicing in CsCCD2, being intron retention (IR) the prevalent form of alternative splicing in CsCCD2. Further, high IR was observed in tissues that do not accumulate crocetin. The analysis of one CsCCD2 promoter showed cis-regulatory motifs involved in the response to light, temperature, and circadian regulation. The light and circadian regulation are common elements shared with the previously characterized CsLycB2a promoter, and these shared common cis-acting elements may represent binding sites for transcription factors responsible for co-regulation of these genes during the development of the stigma in saffron. A daily coordinated rhythmic regulation for CsCCD2 and CsLycB2a was observed, with higher levels of mRNA occurring at low temperatures during darkness, confirming the results obtained in the in silico promoter analysis. In addition, to the light and temperature dependent regulation of CsCCD2 expression, the apocarotenoid ß-cyclocitral up-regulated CsCCD2 expression and could acts as a mediator of chromoplast-to-nucleus signalling, coordinating the expression of CsCCD2 with the developmental state of the chromoplast in the developing stigma.


Assuntos
Carotenoides/metabolismo , Crocus/metabolismo , Dioxigenases/metabolismo , Íntrons/fisiologia , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Carotenoides/biossíntese , Dioxigenases/genética , Dioxigenases/fisiologia , Regulação da Expressão Gênica de Plantas/fisiologia , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia , Regiões Promotoras Genéticas/genética , Regiões Promotoras Genéticas/fisiologia , Vitamina A/análogos & derivados , Zeaxantinas/metabolismo
20.
Int J Mol Sci ; 16(11): 27835-49, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26610480

RESUMO

Dihydroxyacetone (DHA) kinase from Citrobacter freundii provides an easy entry for the preparation of DHA phosphate; a very important C3 building block in nature. To modify the phosphoryl donor specificity of this enzyme from ATP to inorganic polyphosphate (poly-P); a directed evolution program has been initiated. In the first cycle of evolution, the native enzyme was subjected to one round of error-prone PCR (EP-PCR) followed directly (without selection) by a round of DNA shuffling. Although the wild-type DHAK did not show activity with poly-P, after screening, sixteen mutant clones showed an activity with poly-phosphate as phosphoryl donor statistically significant. The most active mutant presented a single mutation (Glu526Lys) located in a flexible loop near of the active center. Interestingly, our theoretical studies, based on molecular dynamics simulations and hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) optimizations, suggest that this mutation has an effect on the binding of the poly-P favoring a more adequate position in the active center for the reaction to take place.


Assuntos
Trifosfato de Adenosina/química , Modelos Moleculares , Fosfotransferases (Aceptor do Grupo Álcool)/química , Polifosfatos/química , Trifosfato de Adenosina/metabolismo , Sítios de Ligação , Biblioteca Gênica , Conformação Molecular , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Mutação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Polifosfatos/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Relação Estrutura-Atividade , Especificidade por Substrato
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