RESUMO
Nuclear receptors (NRs) are ligand-regulated transcription factors that are important for the normal growth and development of insects. However, systematic function analysis of NRs in the molting process of Lasioderma serricorne has not been reported. In this study, we identified and characterized 16 NR genes from L. serricorne. Spatiotemporal expression analysis revealed that six NRs were mainly expressed in 3-d-old 4th-instar larvae; five NRs were primarily expressed in 5-d-old adults and four NRs were predominately expressed in prepupae. All the NRs were highly expressed in epidermis, fat body and foregut. RNA interference (RNAi) experiments revealed that knockdown of 15 NRs disrupted the larva-pupa-adult transitions and caused 64.44-100 % mortality. Hematoxylin-eosin staining showed that depletion of 12 NRs prevented the formation of new cuticle and disrupted apolysis of old cuticle. Silencing of LsHR96, LsSVP and LsE78 led to newly formed cuticle that was thinner than the controls. The 20E titer and chitin content significantly decreased by 17.67-95.12 % after 15 NR dsRNA injection and the gene expression levels of 20E synthesis genes and chitin metabolism genes were significantly reduced. These results demonstrated that 15 NR genes are essential for normal molting and metamorphosis of L. serricorne by regulating 20E synthesis and chitin metabolism.
Assuntos
Besouros , Regulação da Expressão Gênica no Desenvolvimento , Metamorfose Biológica , Muda , Receptores Citoplasmáticos e Nucleares , Animais , Muda/genética , Metamorfose Biológica/genética , Besouros/genética , Besouros/crescimento & desenvolvimento , Besouros/metabolismo , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Larva/genética , Larva/crescimento & desenvolvimento , Quitina/metabolismo , Interferência de RNA , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Filogenia , Ecdisterona/metabolismoRESUMO
Radiation therapy is a common treatment modality for patients with malignant tumors of the head and neck, chest and axilla. However, radiotherapy inevitably causes damage to normal tissues at the irradiated site, among which damage to the brachial plexus nerve(BP) is a serious adverse effect in patients receiving radiation therapy in the scapular or axillary regions, with clinical manifestations including abnormal sensation, neuropathic pain, and dyskinesia, etc. These adverse effects seriously reduce the living quality of patients and pose obstacles to their prognosis. Therefore, it is important to elucidate the mechanism of radiation induced brachial plexus injury (RIBP) which remains unclear. Current studies have shown that the pathways of radiation-induced BP injury can be divided into two categories: direct injury and indirect injury, and the indirect injury is closely related to the inflammatory response, microvascular damage, cytokine production and other factors causing radiation-induced fibrosis. In this review, we summarize the underlying mechanisms of RIBP occurrence and possible effective methods to prevent and treat RIBP.
Assuntos
Neuropatias do Plexo Braquial , Plexo Braquial , Neuralgia , Lesões por Radiação , Humanos , Neuropatias do Plexo Braquial/etiologia , Neuropatias do Plexo Braquial/epidemiologia , Plexo Braquial/efeitos da radiação , Prognóstico , Neuralgia/complicações , Lesões por Radiação/terapia , Lesões por Radiação/complicaçõesRESUMO
Blue mussel (Mytilus edulis L.) is a popular, nutritional, and tasty mollusk. To better understand the composition of nutrients and improve further processing of the mussels, metabolomic approaches were used to analyze the free amino acids, 5'-nucleotides, and lipid compositions of different tissues. Our results showed that the viscera and gonad were rich in glutamine and glycine. Adenosine 5'-monophosphate, uridine 5'-monophosphate, guanosine 5'-monophosphate, and inosine 5'-monophosphate were abundant in the mantle, foot, and adductor muscle. Three main types of lipids, phospholipids (PLs), glycerides, and fatty acids (FAs), were semi-quantified. PLs were mainly distributed in the gonad of male mussels and viscera, gonad, and mantles of female mussels. FAs were relatively high in the viscera of males and in the gonad and viscera of females. The viscera of females were rich in phosphatidylcholine, such as 16:0/22:6 and 16:0/20:5. Triglycerides were the key lipids for distinguishing different tissues, especially 16:0/18:1/18:3 and 16:0/18:4/20:5.
Assuntos
Mytilus edulis , Aminoácidos , Animais , Feminino , Masculino , Espectrometria de Massas , Metabolômica , Nucleotídeos , FosfolipídeosRESUMO
The genus Orthonairovirus, which is part of the family Nairoviridae, includes the important tick-transmitted pathogens Crimean-Congo hemorrhagic fever virus and Nairobi sheep disease virus, as well as many other poorly characterized viruses found in ticks, birds and mammals1,2. In this study, we identified a new orthonairovirus, Songling virus (SGLV), from patients who reported being bitten by ticks in Heilongjiang Province in northeastern China. SGLV shared similar genomic and morphological features with orthonairoviruses and phylogenetically formed a unique clade in Tamdy orthonairovirus of the Nairoviridae family. The isolated SGLV induced cytopathic effects in human hepatoma cells in vitro. SGLV infection was confirmed in 42 hospitalized patients analyzed between 2017 and 2018, with the main clinical manifestations being headache, fever, depression, fatigue and dizziness. More than two-thirds (69%) of patients generated virus-specific antibody responses in the acute phase. Taken together, these results suggest that this newly discovered orthonairovirus is associated with human febrile illness in China.
Assuntos
Febre/complicações , Nairovirus/isolamento & purificação , Nairovirus/patogenicidade , Doenças Transmitidas por Carrapatos/virologia , Viroses/virologia , Adulto , Idoso , China , Feminino , Febre/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Transmitidas por Carrapatos/complicações , Viroses/complicaçõesRESUMO
BACKGROUND: Studies suggest that overweight and obese breast cancer survivors are at increased risk of cancer recurrence and have higher all-cause mortality. Obesity has an impact on breast cancer survivor's quality of life (QOL) and increases the risk of longer-term morbidities such as type 2 diabetes mellitus and cardiovascular disease. Many cancer guidelines recommend survivors maintain a healthy weight but there is a lack of evidence regarding which weight loss method to recommend. OBJECTIVES: To assess the effects of different body weight loss approaches in breast cancer survivors who are overweight or obese (body mass index (BMI) ≥ 25 kg/m2). SEARCH METHODS: We carried out a search in the Cochrane Breast Cancer Group's (CBCG's) Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL, Issue 6), MEDLINE (2012 to June 2019), Embase (2015 to June 2019), the World Health Organisation International Clinical Trials Registry Platform (WHO ICTRP) and Clinicaltrials.gov on 17 June 2019. We also searched Mainland Chinese academic literature databases (CNKI), VIP, Wan Fang Data and SinoMed on 25 June 2019. We screened references in relevant manuscripts. SELECTION CRITERIA: We included randomised controlled trials (RCTs), quasi-RCTs and randomised cross-over trials evaluating body weight management for overweight and obese breast cancer survivors (BMI ≥ 25 kg/m2). The aim of the intervention had to be weight loss. DATA COLLECTION AND ANALYSIS: Two review authors independently performed data extraction and assessed risk of bias for the included studies, and applied the quality of the evidence using the GRADE approach. Dichotomous outcomes were analysed as proportions using the risk ratio (RR) as the measure of effect. Continuous data were analysed as means with the measure of effect being expressed as the mean differences (MDs) between treatment groups in change from baseline values with 95% confidence intervals (CIs), when all studies reported exactly the same outcomes on the same scale. If similar outcomes were reported on different scales the standardised mean difference (SMD) was used as the measure of effect. Quality of life data and relevant biomarkers were extracted where available. MAIN RESULTS: We included a total of 20 studies (containing 23 intervention-comparisons) and analysed 2028 randomised women. Participants in the experimental groups received weight loss interventions using the core element of dietary changes, either in isolation or in combination with other core elements such as 'diet and exercise', 'diet and psychosocial support' or 'diet, exercise and psychosocial support'. Participants in the controls groups either received usual care, written materials or placebo, or wait-list controls. The duration of interventions ranged from 0.5 months to 24 months. The duration of follow-up ranged from three months to 36 months. There were no time-to-event data available for overall survival, breast cancer recurrence and disease-free survival. There was a relatively small amount of data available for breast cancer recurrence (281 participants from 4 intervention-comparisons with 14 recurrence events; RR 1.95, 95% CI 0.68 to 5.60; low-quality evidence) and the analysis was likely underpowered. Overall, we found low-quality evidence that weight loss interventions for overweight and obese breast cancer survivors resulted in a reduction in body weight (MD: -2.25 kg, 95% CI: -3.19 to -1.3 kg; 21 intervention-comparisons; 1751 women), body mass index (BMI) (MD: -1.08 kg/m2, 95% CI: -1.61 to -0.56 kg/m2; 17 intervention-comparisons; 1353 women), and waist circumference (MD:-1.73 cm, 95% CI: -3.17 to -0.29 cm; 13 intervention-comparisons; 1193 women), and improved overall quality of life (SMD: 0.74; 95% CI: 0.20 to 1.29; 10 intervention-comparisons; 867 women). No increase was seen in adverse events for women in the intervention groups compared to controls (RR 0.94, 95% CI: 0.76 to 1.17; 4 intervention-comparisons; 394 women; high-quality evidence). Subgroup analyses revealed that decreases in body weight, BMI and waist circumference were present in women regardless of their ethnicity and menopausal status. Multimodal weight loss interventions (which referred to 'diet, exercise and psychosocial support') appeared to result in greater reductions in body weight (MD: -2.88 kg, 95% CI: -3.98 to -1.77 kg; 13 intervention-comparisons; 1526 participants), BMI (MD: -1.44 kg/m2, 95% CI: -2.16 to -0.72 kg/m2; 11 studies; 1187 participants) and waist circumference (MD:-1.66 cm, 95% CI: -3.49 to -0.16 cm; 8 intervention-comparisons; 1021 participants) compared to dietary change alone, however the evidence was low quality. AUTHORS' CONCLUSIONS: Weight loss interventions, particularly multimodal interventions (incorporating diet, exercise and psychosocial support), in overweight or obese breast cancer survivors appear to result in decreases in body weight, BMI and waist circumference and improvement in overall quality of life. There was no increase in adverse events. There is a lack of data to determine the impact of weight loss interventions on survival or breast cancer recurrence. This review is based on studies with marked heterogeneity regarding weight loss interventions. Due to the methods used in included studies, there was a high risk of bias regarding blinding of participants and assessors. Further research is required to determine the optimal weight loss intervention and assess the impact of weight loss on survival outcomes. Long-term follow-up in weight loss intervention studies is required to determine if weight changes are sustained beyond the intervention periods.
Assuntos
Neoplasias da Mama/complicações , Sobreviventes de Câncer , Obesidade/terapia , Sobrepeso/terapia , Redução de Peso , Índice de Massa Corporal , Neoplasias da Mama/epidemiologia , Terapia Combinada/métodos , Exercício Físico , Feminino , Humanos , Recidiva Local de Neoplasia/epidemiologia , Psicoterapia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Circunferência da Cintura , Programas de Redução de PesoRESUMO
As an essential carrier of hazardous substances, fugitive road dust has become a severe issue in China. In this study, 212 road dust samples from 53 cities in China were collected to comprehensively investigate the spatial variations, potential sources, and cancer risk of 16 polycyclic aromatic hydrocarbons (PAHs) and 16 nitro-PAHs. The total PAHs concentrations ranged from 0.07 to 345 µg/g dry weight, which is at a moderate level compared to other regions in the world. The mean concentration of Σ16nitro-PAHs was 111 ± 115 ng/g, which is 2-3 orders of magnitude lower than that of Σ16PAHs. A clear geographical trend of dust PAHs and nitro-PAHs was observed in the northeast, north, and east coastal regions of China at a higher level. Moreover, a significant correlation between latitude and PAHs/nitro-PAHs revealed the influences of outdoor temperature and coal combustion for heating in the different regions on the emission and reaction of PAHs and nitro-PAHs. The secondary formation of most nitro-PAHs increases with a decrease in latitude indicated that solar radiation and temperature are important factors on secondary formation of nitro-PAHs. The average concentration of total PAHs and their derivatives in trunk road samples were statistically higher than those in other road samples (p < 0.05), indicating the influence of traffic load on target compound concentration. Generally, the primary sources of PAHs in the road dust samples were coal combustion (23.9%), vehicles (57.1%), and wood/biomass combustion (19.0%). For nitro-PAHs, the main sources were secondary formation (30.9%), biomass/coal combustion (28.4%), and vehicles (44.9%). Furthermore, a moderate potential carcinogenic risk due to PAHs and nitro-PAHs in the dust samples was found in China.
Assuntos
Hidrocarbonetos Policíclicos Aromáticos , China , Cidades , Poeira/análise , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de RiscoRESUMO
BACKGROUND: To compare neonatal mortality and neurodevelopmental outcomes at two years of age in very low birth weight infants (≤1500 g) born by cesarean with those by vaginal delivery. METHODS: In this retrospective, case-control study, we evaluated neonatal mortality, medical conditions and neurodevelopmental outcomes at two years of corrected age in 710 very low birth weight (VLBW) infants born between January 2005 and December 2010. Of the 710 infants, 351 were born by the cesarean and 359/710 by vaginal route. RESULTS: There were no significant differences in neonatal mortality between the cesarean delivery group and vaginal delivery group [56/351 (15.9%) vs. 71/359 (19.8%), P=0.20]. VLBW infants delivered by the cesarean procedure had a higher incidence of respiratory distress syndrome than those born by the vaginal route [221/351 (63.0%) vs. 178/359 (49.6%), P<0.001]. There were no differences in other neonatal morbidities, including intraventricular hemorrhage [126/351 (35.9%) vs. 134/359 (37.3%), P=0.69], bronchopulmonary dysplasia [39/351 (11%) vs. 31/359 (8.6%), P=0.38] and necrotising enterocolitis [40/351 (11.4%) vs. 32/359 (8.9%), P=0.32] between the two groups. The incidence of poor neurodevelopment after cesarean delivery was similar to that after vaginal delivery [105/351 (29.9) vs. 104/359 (29.0%), P=0.78]. CONCLUSIONS: In neither neurodevelopment nor neonatal mortality did cesarean birth offered significant advantages to VLBW infants. Moreover, the operation might be associated with an increased risk of respiratory distress syndrome for VLBW infants. The mode of delivery of VLBW infants should be largely based on obstetric indications and maternal considerations rather than perceived better outcomes for the neonate.
Assuntos
Cesárea/estatística & dados numéricos , Parto Obstétrico/estatística & dados numéricos , Deficiências do Desenvolvimento/epidemiologia , Mortalidade Infantil , Recém-Nascido de muito Baixo Peso , Estudos de Casos e Controles , Hemorragia Cerebral/epidemiologia , Cesárea/mortalidade , Pré-Escolar , China/epidemiologia , Parto Obstétrico/mortalidade , Deficiências do Desenvolvimento/mortalidade , Feminino , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Gravidez , Síndrome do Desconforto Respiratório do Recém-Nascido/epidemiologia , Estudos Retrospectivos , Medição de Risco , Fatores de RiscoRESUMO
BACKGROUND: There is no curative treatment for chronic fatigue syndrome (CFS). Traditional Chinese medicine (TCM) is widely used in the treatment of CFS in China. OBJECTIVE: To evaluate the effectiveness and safety of TCM for CFS. METHODS: The protocol of this review is registered at PROSPERO. We searched six main databases for randomized clinical trials (RCTs) on TCM for CFS from their inception to September 2013. The Cochrane risk of bias tool was used to assess the methodological quality. We used RevMan 5.1 to synthesize the results. RESULTS: 23 RCTs involving 1776 participants were identified. The risk of bias of the included studies was high. The types of TCM interventions varied, including Chinese herbal medicine, acupuncture, qigong, moxibustion, and acupoint application. The results of meta-analyses and several individual studies showed that TCM alone or in combination with other interventions significantly alleviated fatigue symptoms as measured by Chalder's fatigue scale, fatigue severity scale, fatigue assessment instrument by Joseph E. Schwartz, Bell's fatigue scale, and guiding principle of clinical research on new drugs of TCM for fatigue symptom. There was no enough evidence that TCM could improve the quality of life for CFS patients. The included studies did not report serious adverse events. CONCLUSIONS: TCM appears to be effective to alleviate the fatigue symptom for people with CFS. However, due to the high risk of bias of the included studies, larger, well-designed studies are needed to confirm the potential benefit in the future.
Assuntos
Síndrome de Fadiga Crônica/terapia , Medicina Tradicional Chinesa/métodos , Terapia por Acupuntura , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
The aim of this study was to investigate the associations between STAT5 gene polymorphisms and glioblastoma (GBM) risk predisposition. We undertook a case-control study to analyze two STAT5 polymorphisms (STAT5a rs11079041 and STAT5b rs2293157) in a Han Chinese population, by extraction of genomic DNA from the peripheral blood of 328 patients with glioma and 342 control participants, and performed STAT5 genotyping using DNA sequencing. The obtained results indicated that overall, no statistically significant association was observed in STAT5a rs11079041. Nevertheless, STAT5b rs2293157 G/T genotype was at increased risk of glioma (P=0.001). Furthermore, rs2293157T allele was more significantly prognostic in patients suffering from glioblastoma compared to other subtypes of gliomas (P<0.001; odds ratio (OR)=5.14, CI 95%: 2.70-9.79). These findings led us to conclude that polymorphism in STAT5b rs2293157 G/T was observed to be associated with susceptibility of glioblastoma. Nevertheless, further investigation with a later confirmation in another ethnical or geographical cohort is required.
Assuntos
Neoplasias Encefálicas/genética , Predisposição Genética para Doença , Glioblastoma/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT5/genética , Adulto , Alelos , Povo Asiático/genética , Neoplasias Encefálicas/patologia , Estudos de Casos e Controles , China , Feminino , Estudos de Associação Genética , Genótipo , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Our previous study showed that trans-fatty acids can cause apoptosis of endothelial cells through the caspase pathway and the mitochondrial pathway. The objective of this study was to explore how trans-fatty acids activate the caspase pathway, whether there exist specific receptors induced apoptosis by comparing normal cells and non-rafts cells treated with elaidic acid (9t18:1) and oleic acid (9c18:1), respectively. Compared to normal cells treated with 9t18:1, the cell viability increased by 13% and the number of apoptotic cells decreased by 3% in non-rafts cells treated with 9t18:1 (p < 0.05), and the expression levels of pro-apoptotic proteins such as caspase-3, -8, -9, Bax, and Bid decreased, and expression of antiapoptotic protein Bcl-2 increased (p < 0.05). In addition, Fas/FasL expression in cell membrane decreased significantly (p < 0.05). In conclusion, the lipid rafts and Fas/FasL pathway may involve in 9t18:1-induced apoptosis of human umbilical vein endothelial cells.
Assuntos
Apoptose/efeitos dos fármacos , Proteína Ligante Fas/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Microdomínios da Membrana/metabolismo , Ácido Oleico/metabolismo , Receptor fas/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Sobrevivência Celular , Humanos , Ácido Oleico/química , Ácidos Oleicos , Transdução de SinaisRESUMO
Different carrier molecules have been fused to antimicrobial polypeptides (AMPs) to facilitate recombinant protein expression and purification. Some of them have improved the stability of AMPs and reduced the toxicity to host cells, but most current strategies still have some problems to be solved such as poor yield, low purity, high expense, time-consumption, and difficulty in scaling-up. Here, we introduced the elastin-like polypeptides (ELPs) as a fusion partner to express an antimicrobial polypeptide halocidin18 (Hal18). By the reversible soluble-insoluble phase transition, 69 mg of the fusion protein were purified from 1 l of culture medium with the purity of nearly 95%. After cleavage with hydroxylamine, the ELP's tag was easily separated from Hal18 in the next round of inverse transition cycle and Hal18 (1.7 mg, approximately 1.9 kDa) was mainly found in the supernatant with a recovery of about 47% and purity of 60%. Antimicrobial activity showed that Hal18 had strong antimicrobial activity against Escherichia coli and Micrococcus luteus but weak activity against Pichia pastoris.
Assuntos
Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/metabolismo , Elastina/isolamento & purificação , Elastina/metabolismo , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismo , Sequência de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Elastina/genética , Elastina/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologiaRESUMO
Elastin-like polypeptides (ELPs) are biological macromolecules designed on the elastic structure and composition. ELPs are thermally responsive polypeptides that undergo reversible inverse phase transition. Below their inverse transition temperature (Tt), ELPs are soluble in water, but when the temperature is raised above Tt, phase transition occurs, leading to aggregation of the polypeptide. Based on this property of ELPs, we investigated the ELPs as a fusion partner for the expression and purification of the antimicrobial polypeptide halocidin18 (18-amino-acid subunit, Hal18). According to the amino acid sequence of hal18 and the bias for preferred codons of E. coli, the hal18 gene was synthesized by reverse PCR method and fused with the ELPs gene; the fusion gene was cloned into the prokaryotic expression vector pET23a to construct a recombinant expression vector pETH9E and then transformed into E. coli BL21 (DE3) to overexpress the recombinant fusion protein H9E. H9E was purified by inverse transition cycling (ITC) from the soluble fraction of the lysed E. coli. SDS-PAGE analysis results demonstrated that one-round of ITC purification could remove most of the contaminated proteins, and second-round could increase the purity of the fusion protein up to 95%. After cleavage and dialysis, Hal18 showed strong antimicrobial activities against E. coli and M. luteus which were used as representative gram-negative and gram-positive bacteria, respectively. The results demonstrate that ELPs is an ideal fusion protein to express and purify the antimicrobial polypeptides.
Assuntos
Antibacterianos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Elastina/isolamento & purificação , Expressão Gênica , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bactérias/efeitos dos fármacos , Elastina/genética , Elastina/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismoRESUMO
According to the published DNA sequence, a serial of elements for constructing the tobacco chloroplast multicistron site integrating expression vectors have been cloned by PCR technique, which include Prrn (a modified plastid ribosomal RNA operon promoter), psbA3' (the 3' region of the plastid psbA gene), aadA gene (encoding aminoglycoside 3'-adenylytransferase), man gene (encoding mannase), gfp gene (encoding green fluorescence protein) and tobacco chloroplast high-frequency homologous recombination ctDNA fragment (psaA/psbC, 3463 bp) (Fig.2). A tobacco chloroplast multicistron expression vector pLM4 (Fig.1) (-psaA-Prrn-SD-man-SD-gfp-SD-aadA-psbA3'- psbC-) was constructed with these elements. Then the tobacco leaves were bombarded 5 times with gold particles coated with the vector pLM4. After growing on the screening medium, the function of aadA gene was identified (Fig.3), and the function of gfp gene was confirmed by laser scanner (Fig.4), the expression of man was identified by Western blot (Fig.5). All these genes man, gfp and aadA being integrated in the tobacco chloroplast genome DNA were confirmed by PCR (Fig.6). And the multicistron expression cassette integrating in tobacco chloroplast genome DNA was confirmed by RFLP (Fig.7). All these showed that the three genes in the tomato vector pLM4 were expressed in tobacco chloroplast genome DNA.
Assuntos
DNA de Cloroplastos/genética , Vetores Genéticos/genética , Nicotiana/genética , Transgenes/genética , Sítios de Ligação/genética , Western Blotting , Técnicas de Transferência de Genes , Genes , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de RestriçãoRESUMO
Laccase(EC1.10.3.2) can be used for enzymatic detoxification of lignocellulosic hydrolysates. By using molecular techniques such as RACE (rapid amplification of cDNA ends) and Genome-Walking, a laccase gene and its corresponding full-length cDNA were cloned from Flammulina velutipes and designated as glccFv and IccFv. The sequences were submitted to GenBank, and the accession numbers obtained were AY485826 and AY450406, respectively. Analysis of amino acids sequence suggested that one laccase from Polyporus ciliatus possessed the highest homology with the protein encoded by lccFv showing for 72%. The ORF (open reading frame) of lccFv was transformed into Pichia pastoris strain GS115 through the P. pastoris expression vector pHBM906, which contains both the promoter and transcription terminator of the AOX1 gene. The recombinant laccase LCCFv was detected from the engineering strain GS115 (pHBM557) which was fermented with BMMY liquid medium and induced by 1.0% (V/V) methanol at 20 degrees C with the highest expression level (0.1070 U/mL). The optimal reaction temperature of LCCFv that secreted from P. pastoris GS115(pHBM557) was 45 degrees C, the optimal reaction pH value was pH3.9 and the thermostability and pH stability were very well under the optimal conditions.
Assuntos
Flammulina/enzimologia , Lacase/genética , Pichia/genética , Sequência de Bases , Clonagem Molecular , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Lacase/metabolismo , Dados de Sequência Molecular , Técnicas de Amplificação de Ácido Nucleico , Plasmídeos , Proteínas Recombinantes/biossínteseRESUMO
Arresten as a endogenous inhibitor of angiogenesis originated from the carboxyl-terminal 223 amino acids fragment of the non-collagen domain in alpha1 chain of human collagen IV. In order to get the soluble arresten with biological activity, the cDNA of arresten was cloned and expressed in Pichia pastoris. The produced arresten cDNA was amplified by PCR using primer P1:5'-AGGCCCCGATGGGTTGC-3', primer P2:5'-CTATAAG GCACTTTACGGTTTC-3'. The PCR products was cloned into pGEM-T vector, and sequenced. The arresten cDNA from pGEM-T vector was recombined with vector pPIC9 as pPIC9-arresten, used to transform E. coli DH5alpha, and the inserted arresten cDNA confirmed by agarose electrophoresis and sequencing. pPIC9-arresten was linearized by Sac I. Pichia pastoris GS115 was treated with PEG1000 (followed Invitrogen' s specification); transformed with linear recombined pPIC9-arresten. Pichia pastoris GS115 was culured on MD mediun, single clone was selected and the DNA from the single clone was extracted, used as template, characterized by PCR using the second pair primers P3:5'-CGCTCGAGAAAAGATCTGTTGATC-3', P4:5'-GCCCCGG ATCCTTATGTTCTFCTCATACAG-3'. The polynucleotides CTCGAGAAAAGA used as marker sequence was inserted into primer P3 for signal peptidase to cleave off the signal sequence correctively. The recombined Pichia pastoris GS115 was selected according to the results of PCR, cultured on MM and MD media and then in the BMGY media using methanol as inducer. Expressed arresten was analysed by SDS-PAGE. The soluble arresten expressed by Pichia pastoris gave apparent molecular weight in SDS-PAGE consistent with that calculated, and in matrigel gel it showed inhibitary activity on the tubulation of endothelial cell ECV-304 induced by tumor cell MDA-MB-435S. These results showesd arresten with biological activity is expressed successfully in Pichia pastoris GS115.