Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
1.
Plant Cell Environ ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38774965

RESUMO

Boron (B) is an essential microelement in plant growth and development. However, the molecular mechanisms underlying B uptake and translocation in Brassica napus are poorly understood. Herein, we identified a low-B (LB)-inducible gene, namely BnaC4.BOR2, with high transcriptional activity in root tips, stele cells, leaves, and floral organs. The green fluorescence protein labelled BnaC4.BOR2 protein was localised to the plasma membrane to demonstrate the B efflux activity in yeast and Arabidopsis. BnaC4.BOR2 knockout considerably reduced B concentration in the root and xylem sap, and altered B distribution in different organs at low B supply, exacerbating B sensitivity at the vegetative and reproductive stages. Additionally, the grafting experiment showed that BnaC4.BOR2 expression in the roots contributed more to B deficiency adaptability than that in the shoots. The pot experiments with LB-soil revealed B concentration in leaves and siliques of BnaC4.BOR2 mutants were markedly reduced, showing an obvious B-deficient phenotype of 'flowering without seed setting' and a considerable reduction in seed yield in B-deficient soil. Altogether, the findings of this study highlight the crucial role of BnaC4.BOR2 in B uptake and translocation during B. napus growth and seed yield under LB conditions.

2.
Infect Immun ; 91(1): e0037822, 2023 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-36602381

RESUMO

Recent studies have found that the coexistence of fungi and bacteria in the airway may increase the risk of infection, contribute to the development of pneumonia, and increase the severity of disease. Interleukin 17A (IL-17A) plays important roles in host resistance to bacterial and fungal infections. The objective of this study was to determine the effects of IL-17A on Acinetobacter baumannii-infected rats with a previous Candida albicans airway inoculation. The incidence of A. baumannii pneumonia was higher in rats with C. albicans in the airway than in noninoculated rats, and it decreased when amphotericin B was used to clear C. albicans, which influenced IL-17A levels. IL-17A had a protective effect in A. baumannii pneumonia associated with C. albicans in the airway. Compared with A. baumannii-infected rats with C. albicans in the airway that did not receive IL-17A, recombinant IL-17A (rIL-17A) supplementation decreased the incidence of A. baumannii pneumonia (10/15 versus 5/17; P = 0.013) and the proportion of neutrophils in the lung (84 ± 3.5 versus 74 ± 4.3%; P = 0.033), reduced tissue destruction and inflammation, and decreased levels of myeloperoxidase (MPO) (1.267 ± 0.15 versus 0.233 ± 0.06 U/g; P = 0.0004), reactive oxygen species (ROS) (132,333 ± 7,505 versus 64,667 ± 10,115 AU; P = 0.0007) and lactate dehydrogenase (LDH) (2.736 ± 0.05 versus 2.1816 ± 0.29 U/g; P = 0.0313). In vitro experiments revealed that IL-17A had no significant effect on the direct migration ability and bactericidal capability of neutrophils. However, IL-17A restrained lysis cell death and increased apoptosis of neutrophils (2.9 ± 1.14 versus 7 ± 0.5%; P = 0.0048). Taken together, our results suggest that C. albicans can depress IL-17A levels, which when supplemented may have a regulatory function that limits the accumulation of neutrophils in inflammatory areas, providing inflammatory response homeostasis.


Assuntos
Infecções por Acinetobacter , Acinetobacter baumannii , Pneumonia Bacteriana , Pneumonia , Ratos , Animais , Candida albicans/metabolismo , Interleucina-17/metabolismo , Acinetobacter baumannii/metabolismo , Pulmão/metabolismo , Neutrófilos/metabolismo , Bactérias/metabolismo
3.
Plant Biotechnol J ; 18(5): 1241-1254, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31705705

RESUMO

Boron (B) deficiency is one of the major causes of growth inhibition and yield reduction in Brassica napus (B. napus). However, the molecular mechanisms of low B adaptation in B. napus are largely unknown. Here, fifty-one BnaWRKY transcription factors were identified as responsive to B deficiency in B. napus, in which BnaAn.WRKY26, BnaA9.WRKY47, BnaA1.WKRY53 and BnaCn.WRKY57 were tested in yeast one-hybrid assays and showed strong binding activity with conserved sequences containing a W box in the promoters of the B transport-related genes BnaNIP5;1s and BnaBOR1s. Green fluorescent protein fused to the target protein demonstrated the nuclear localization of BnaA9.WRKY47. CRISPR/Cas9-mediated knockout lines of BnaA9.WRKY47 in B. napus had increased sensitivity to low B and lower contents of B than wild-type plants. In contrast, overexpression of BnaA9.WRKY47 enhanced the adaptation to low B with higher B contents in tissues than in wild-type plants. Consistent with the phenotypic response and B accumulation in these transgenic lines, the transcription activity of BnaA3.NIP5;1, a B efficiency candidate gene, was decreased in the knockout lines but was significantly increased in the overexpressing lines under low B conditions. Electrophoretic mobility shift assays, transient expression experiments in tobacco and in situ hybridizations showed that BnaA9.WRKY47 directly activated BnaA3.NIP5;1 expression through binding to the specific cis-element. Taken together, our findings support BnaWRKYs as new participants in response to low B, and BnaA9.WRKY47 contributes to the adaptation of B. napus to B deficiency through up-regulating BnaA3.NIP5;1 expression to facilitate efficient B uptake.


Assuntos
Brassica napus , Ácidos Bóricos , Boro/metabolismo , Brassica napus/genética , Brassica napus/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
4.
Plant Cell Environ ; 43(3): 712-731, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31759338

RESUMO

Considerable genetic variation in agronomic nitrogen (N) use efficiency (NUE) has been reported among genotypes of Brassica napus. However, the physiological and molecular mechanisms underpinning these differences remain poorly understood. In this study, physiological and genetic factors impacting NUE were identified in field trials and hydroponic experiments using two B. napus genotypes with contrasting NUE. The results showed that the N-efficient genotype (D4-15) had greater N uptake and utilization efficiencies, more root tips, larger root surface and root volume, and higher N assimilation and photosynthesis capacity than the N-inefficient genotype (D2-1). Genomic analysis revealed that D4-15 had a greater genome diversity related to NUE than D2-1. By combining genomic and transcriptomic analysis, genes involved in photosynthesis and C/N metabolism were implicated in conferring NUE. Co-expression network analysis of genes that differed between the two genotypes suggested gene clusters impacting NUE. A nitrate transporter gene BnaA06g04560D (NRT2.1) and two vacuole nitrate transporter CLC genes (BnaA02g11800D and BnaA02g28670D) were up-regulated by N starvation in D4-15 but not in D2-1. The study revealed that high N uptake and utilization efficiencies, maintained photosynthesis and coordinated C/N metabolism confer high NUE in B. napus, and identified candidate genes that could facilitate breeding for enhanced NUE in B. napus.


Assuntos
Brassica napus/genética , Perfilação da Expressão Gênica , Genoma de Planta , Nitrogênio/metabolismo , Aminoácidos/metabolismo , Proteínas de Transporte de Ânions/genética , Proteínas de Transporte de Ânions/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassica napus/efeitos dos fármacos , Carbono/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Variação Genética/efeitos dos fármacos , Genótipo , Hidroponia , Transportadores de Nitrato , Nitrogênio/farmacologia , Fotossíntese/efeitos dos fármacos , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Solubilidade , Soluções , Açúcares/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética
5.
Ann Bot ; 114(3): 549-59, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24989788

RESUMO

BACKGROUND AND AIMS: Oilseed rape (Brassica napus) is an important oil crop worldwide. The aim of this study was to identify the variation in nitrogen (N) efficiency of new-type B. napus (genome A(r)A(r)C(c)C(c)) genotypes, and to characterize some critical physiological and molecular mechanisms in response to N limitation. METHODS: Two genotypes with contrasting N efficiency (D4-15 and D1-1) were identified from 150 new-type B. napus lines, and hydroponic and pot experiments were conducted. Root morphology, plant biomass, N uptake parameters and seed yield of D4-15 and D1-1 were investigated. Two traditional B. napus (genome A(n)A(n)C(n)C(n)) genotypes, QY10 and NY7, were also cultivated. Introgression of exotic genomic components in D4-15 and D1-1 was evaluated with molecular markers. KEY RESULTS: Large genetic variation existed among traits contributing to the N efficiency of new-type B. napus. Under low N levels at the seedling stage, the N-efficient new-type D4-15 showed higher values than the N-inefficient D1-1 line and the traditional B. napus QY10 and NY7 genotypes with respect to several traits, including root and shoot biomass, root morphology, N accumulation, N utilization efficiency (NutE), N uptake efficiency (NupE), activities of nitrate reductase (NR) and glutamine synthetase (GS), and expression levels of N transporter genes and genes that are involved in N assimilation. Higher yield was produced by the N-efficient D4-15 line compared with the N-inefficient D1-1 at maturity. More exotic genome components were introgressed into the genome of D4-15 (64·97 %) compared with D1-1 (32·23 %). CONCLUSIONS: The N-efficient new-type B. napus identified in this research had higher N efficiency (and tolerance to low-N stress) than traditional B. napus cultivars, and thus could have important potential for use in breeding N-efficient B. napus cultivars in the field.


Assuntos
Brassica napus/genética , Brassica napus/metabolismo , Genótipo , Nitrogênio/metabolismo , Hibridização Genética , Nitrogênio/deficiência , Plântula
6.
Plant Physiol Biochem ; 208: 108508, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38490152

RESUMO

Boron (B) is essential for plant growth. However, the molecular mechanism of B transport in rapeseed (Brassica napus L.) is unknown well. Here, we report that B transporter BnaA4.BOR2 is involved in the transport of B from root to shoot and its distribution in shoot cell wall and flower in rapeseed. The results of GUS staining and in-situ PCR analysis showed that BnaA4.BOR2 is mainly expressed in cortex and endodermis of root tip meristem zone and endodermis of mature zone. BnaA4.BOR2 was mainly localized in plasma membrane and showed B transport activity in yeast. Overexpression of Bna4.BOR2 could rescue the phenotype of Arabidopsis mutant bor2-2 under low-B condition. Furthermore, knockout of BnaA4.BOR2 could significantly enhance the sensitivity of rapeseed mutants to B deficiency, including inhibition of root elongation and biomass decrease of roots and shoots. The B concentration in xylem sap of BnaA4.BOR2 mutants was significantly decreased under B deficiency, which resulted in significantly lower B concentrations in shoot cell wall at seedling stage and flower organ at reproductive stage compared to that of wild-type QY10. The growth of BnaA4.BOR2 mutants were severely inhibited, exhibiting a typical B-deficient phenotype of "flowering without seed setting", leading to a sharp decrease in seed yield in B deficient soil. Taken together, these results indicate that BnaA4.BOR2 is critical for rapeseed growth and seed yield production under low B level, which is mainly expressed in cortex and endodermis, and contributed to the transport of B from roots to shoots and its distribution in shoot.


Assuntos
Arabidopsis , Brassica napus , Brassica rapa , Brassica napus/metabolismo , Boro/metabolismo , Brassica rapa/metabolismo , Arabidopsis/metabolismo , Meristema/metabolismo , Raízes de Plantas/metabolismo
7.
Plant Physiol Biochem ; 208: 108389, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38377886

RESUMO

Purple acid phosphatases (PAPs) are involved in activating the rhizosphere's organic phosphorus (P) and promoting P recycling during plant development, especially under the long-term P deficiency conditions in acid soil. However, the function of BnaPAPs in response to P deficiency stress in Brassica napus has rarely been explored. In this study, we found that the acid phosphatase activities (APA) of rapeseed shoot and root increased under P deficienct conditions. Genome-wide identification found that 82 PAP genes were unevenly distributed on 19 chromosomes in B. napus, which could be divided into eight subfamilies. The segmental duplication events were the main driving force for expansion during evolution, and the gene structures and conserved motifs of most members within the same subfamily were highly conservative. Moreover, the expression levels of 37 and 23 different expressed genes were induced by low P in leaf and root, respectively. BnaA09.PAP10a and BnaC09.PAP10a were identified as candidate genes via interaction networks. Significantly, both BnaPAP10a overexpression lines significantly increased root-related APA and total phosphate concentration under P deficiency and ATP supply conditions, thereby improving plant growth and root length. In summary, our results provided a valuable foundation for further study of BnaPAP functions.


Assuntos
Brassica napus , Brassica napus/metabolismo , Família Multigênica , Homeostase , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Fosfatos/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas/metabolismo
8.
Front Pharmacol ; 14: 1185809, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37324478

RESUMO

Objectives: To investigate the association between traditional Chinese medicine (TCM) therapy and the risk of pneumonia in patients with systemic lupus erythematosus (SLE). Methods: This population-based control study analyzed the data retrieved from the National Health Insurance Research database in Taiwan. From a cohort of 2 million records of the 2000-2018 period, 9,714 newly diagnosed patients with SLE were initially included. 532 patients with pneumonia and 532 patients without pneumonia were matched 1:1 based on age, sex, and year of SLE diagnosis using propensity score matching. The use of TCM therapy was considered from the SLE diagnosis date to the index date and the cumulative days of TCM therapy were used to calculate the dose effect. Conditional logistic regression was used to investigate the risk of pneumonia infection. Furthermore, to explore the severity of pneumonia in SLE, sensitivity analyses were performed after stratification using the parameters of emergency room visit, admission time, and antibiotic use. Results: TCM therapy for >60 days could significantly reduce the risk of pneumonia in patients with SLE (95% CI = 0.46-0.91; p = 0.012). Stratified analysis showed that TCM use also reduced the risk of pneumonia in younger and female patients with SLE by 34% and 35%, respectively. TCM for >60 days significantly reduced the risk of pneumonia in the follow-up periods of >2, >3, >7, and >8 years. In addition, the exposure of TCM for >60 days reduced the risk of pneumonia in patients with SLE who were treated with antibiotics for moderate or severe pneumonia. Finally, the study found that using formulae to tonify the kidney for more than 90 days and formulae to activate blood circulation for less than 30 days could significantly reduce the risk of pneumonia infection in patients with SLE. Conclusion: TCM use is associated with a lower risk of pneumonia among patients with SLE.

9.
Plants (Basel) ; 12(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836101

RESUMO

Inorganic phosphate (Pi) is actively taken up by Pi transporters (PTs) from the soil and transported into the plant. Here, we functionally characterized the Brassica napus gene BnaPT37, which belongs to the PHT1 family. BnaPT37 is a plasma membrane-localized protein containing 534 amino acids. Expression of BnaPT37 increased significantly under Pi deficiency in various tissues, especially in fully expanded leaves. Expression of the ß-glucuronidase reporter gene driven by the BnaPT37 promoter showed that BnaPT37 is expressed in the root, stem, calyx, and leaf under Pi deficiency. BnaPT37 can complement a yeast mutant strain defective in five Pi transporters and can restore the growth of the Arabidopsis atpt1/2 double mutant under Pi deprivation. Overexpression of BnaPT37 in rapeseed significantly increased Pi translocation from root to shoot. Moreover, the movement of Pi from fully expanded leaves to new leaves and roots was enhanced in the transgenic lines compared to the wild type. However, the overexpression of BnaPT37 inhibited the flowering time, plant height, and Pi accumulation in seeds. In conclusion, BnaPT37 functions as a plasma membrane-localized Pi transporter and might be involved in Pi translocation from root to shoot and Pi distribution from source to sink in B. napus.

10.
Plants (Basel) ; 10(10)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34685969

RESUMO

Nitrogen (N) is an essential macronutrient for plants. However, little is known about the molecular regulation of N assimilation in Brassica napus, one of the most important oil crops worldwide. Here, we carried out a comprehensive genome-wide analysis of the N assimilation related genes (NAGs) in B. napus. A total of 67 NAGs were identified encoding major enzymes involved in N assimilation, including asparagine synthetase (AS), glutamate dehydrogenase (GDH), glutamine oxoglutarate aminotransferase (GOGAT), glutamine synthetase (GS), nitrite reductase (NiR), nitrate reductase (NR). The syntenic analysis revealed that segmental duplication and whole-genome duplication were the main expansion pattern during gene evolution. Each NAG family showed different degrees of differentiation in characterization, gene structure, conserved motifs and cis-elements. Furthermore, diverse responses of NAG to multiple nutrient stresses were observed. Among them, more NAGs were regulated by N deficiency and ammonium toxicity than by phosphorus and potassium deprivations. Moreover, 12 hub genes responding to N starvation were identified, which may play vital roles in N utilization. Taken together, our results provide a basis for further functional research of NAGs in rapeseed N assimilation and also put forward new points in their responses to contrasting nutrient stresses.

11.
Plants (Basel) ; 9(10)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050287

RESUMO

Tea (Camellia sinensis (L.) O. Kuntze) leaves are harvested multiple times annually accompanied by a large amount of nitrogen (N) removed. Therefore, tea plantations are characterized by high requirements of N. This study aimed to assess the variations of N-level, apparent N remobilization efficiency (ANRE), and N utilization efficiency (NUtE) and their dynamic changes during growing seasons for twenty tea varieties. The N-level was highest in the one bud with two leaves as the youngest category, followed by mature leaves attached to green-red stems, and then by aging leaves attached to grey stems. The dynamic N-level presented different profiles of "S"-, "U"-, and "S-like"-shape in the three categories of leaves during the growing seasons. Here, specifically defined ANRE indicated N fluxes in a specific category of leaves, showing that sources and sinks alternate during the period of two consecutive rounds of growth. The dynamic of averaged NUtE followed an "S"-shape. The results revealed annual rhythms and physiological characters related with N indices, which were variety dependent and closely related with the amount of N requirements at proper time. An optimized NUtE is a complex character determined by the combination of tea plantation management and breeding practices to achieve sustainable development with economic benefit.

12.
PLoS One ; 14(7): e0220374, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31344115

RESUMO

Phosphate (Pi) transporters play critical roles in Pi acquisition and homeostasis. However, little is known about these transporters in oilseed rape. Therefore, the aim of the present study was to characterize the members of the PHT1 gene family in allotetraploid Brassica napus and to analyze their expression profiles in response to environmental stresses. In total, 49 PHT1 family members were identified in B. napus, including 27 genes in the A subgenome and 22 in the C subgenome. Most of the PHT1 proteins were predicted to localize to the plasma membrane. Phylogenetic analysis suggested that the members of the PHT1 gene family can be divided into seven clades, with the introns/exons and protein motifs conserved in each clade. Collinearity analysis revealed that most of the BnaPHT1 genes shared syntenic relationships with PHT1 members in Arabidopsis thaliana, B. rapa, and B. oleracea, and that whole-genome duplication (polyploidy) played a major driving force for BnaPHT1 evolution in addition to segmental duplication. Transcript abundance analysis showed that a broad range of expression patterns of individual BnaPHT1 genes occurred in response to phosphorus (P) deficiency. In addition, the expression levels of BnaPHT1 genes can be regulated by different nutrient stresses, including nitrogen (N), potassium (K), sulfur (S) and iron (Fe) stresses. Moveover, salt and drought stresses can regulate the transcript abundances of BnaPHT1s, as well as phytohormones including auxin and cytokinin. Gene coexpression analysis based on the RNA-seq data implied that BnaPHT1s might cooperate with each other as well as with other genes to regulate nutrient homeostasis in B. napus. Further analysis of the promoters revealed that GT-1, DRE and P1BS elements are widely distributed within the promoter regions of BnaPHT1 genes. Our results indicate that BnaPHT1s might be involved in cross-talk for sensing the external status of P, N, K, S and Fe, as well as salt and drought stresses. Moreover, these processes might be mediated by phytohormones. Our findings provide the first step in the complex genetic dissection of the Pi transport system in plants and implicate multiple transcriptional regulation, which probably refers to new roles of PHT1 genes in B. napus.


Assuntos
Brassica napus/genética , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/isolamento & purificação , Fósforo/deficiência , Estresse Fisiológico/genética , Arabidopsis/genética , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Clonagem Molecular , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Redes e Vias Metabólicas/genética , Família Multigênica/genética , Proteínas de Transporte de Fosfato/metabolismo , Fósforo/metabolismo , Filogenia , Proteínas de Plantas/genética , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Transcriptoma
13.
J Thorac Oncol ; 11(12): 2129-2140, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27615396

RESUMO

INTRODUCTION: The incidence rate of lung adenocarcinoma (LUAD), the predominant histological subtype of lung cancer, is elevated in Asians, particularly in female nonsmokers. The mutation patterns in LUAD in Asians might be distinct from those in LUAD in whites. METHODS: We profiled 271 resected LUAD tumors (mainly stage I) to characterize the genomic landscape of LUAD in Asians with a focus on female nonsmokers. RESULTS: Mutations in EGFR, KRAS, erb-b2 receptor tyrosine kinase 2 gene (ERBB2), and BRAF; gene fusions involving anaplastic lymphoma receptor tyrosine kinase gene (ALK), ROS1, and ret proto-oncogene (RET); and Met Proto-Oncogene Tyrosine Kinase (MET) exon 14 skipping were the major drivers in LUAD in Asians, exhibiting mutually exclusive and differing prevalence from those reported in studies of LUAD in non-Asians. In addition, we identified a novel mutational signature of XNX (the mutated base N in the middle flanked by two identical bases at the 5' and 3' positions) that was overrepresented in LUAD tumors in nonsmokers and negatively correlated with the overall mutational frequency. CONCLUSIONS: In this cohort, approximately 85% of individuals have known driver mutations (EGFR 59.4%, KRAS 7.4%, ALK 7.4%, ERBB2 2.6%, ROS1 2.2%, RET 2.2%, MET 1.8%, BRAF 1.1%, and NRAS 0.4%). Seventy percent of smokers and 90% of nonsmokers had defined oncogenic drivers matching the U.S. Food and Drug Administration-approved targeted therapies.


Assuntos
Adenocarcinoma/genética , Povo Asiático/genética , Carcinogênese/genética , Neoplasias Pulmonares/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proto-Oncogene Mas , Adulto Jovem
14.
PLoS One ; 8(4): e60801, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23573285

RESUMO

Phytate is the major storage form of organic phosphorus in soils and plant seeds, and phosphorus (P) in this form is unavailable to plants or monogastric animals. In the present study, the phytase genes phyA and appA were introduced into Brassica napus cv Westar with a signal peptide sequence and CaMV 35S promoter, respectively. Three independent transgenic lines, P3 and P11 from phyA and a18 from appA, were selected. The three transgenic lines exhibited significantly higher exuded phytase activity when compared to wild-type (WT) controls. A quartz sand culture experiment demonstrated that transgenic Brassica napus had significantly improved P uptake and plant biomass. A soil culture experiment revealed that seed yields of transgenic lines P11 and a18 increased by 20.9% and 59.9%, respectively, when compared to WT. When phytate was used as the sole P source, P accumulation in seeds increased by 20.6% and 46.9% with respect to WT in P11 and a18, respectively. The P3 line accumulated markedly more P in seeds than WT, while no significant difference was observed in seed yields when phytate was used as the sole P source. Phytase activities in transgenic canola seeds ranged from 1,138 to 1,605 U kg(-1) seeds, while no phytase activity was detected in WT seeds. Moreover, phytic acid content in P11 and a18 seeds was significantly lower than in WT. These results introduce an opportunity for improvement of soil and seed phytate-P bioavailability through genetic manipulation of oilseed rape, thereby increasing plant production and P nutrition for monogastric animals.


Assuntos
6-Fitase/genética , Fosfatase Ácida/genética , Brassica napus/genética , Proteínas de Escherichia coli/genética , Proteínas Fúngicas/genética , Organofosfatos/metabolismo , Sementes/genética , 6-Fitase/biossíntese , Fosfatase Ácida/biossíntese , Aspergillus niger/enzimologia , Brassica napus/crescimento & desenvolvimento , Brassica napus/metabolismo , Proteínas de Escherichia coli/biossíntese , Proteínas Fúngicas/biossíntese , Expressão Gênica , Ácido Fítico/metabolismo , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Solo/química
15.
Sci China Life Sci ; 54(12): 1134-42, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22227906

RESUMO

Genotypic variations in the adaptive response to low-phosphorus (P) stress and P-uptake efficiency have been widely reported in many crops. We conducted a pot experiment to evaluate the P-acquisition ability of two rapeseed (Brassica napus) genotypes supplied with two sparingly soluble sources of P, Al-P and Fe-P. Then, the root morphology, proton concentrations, and carboxylate content were investigated in a solution experiment to examine the genotypic difference in P-acquisition efficiency. Both genotypes produced greater biomass and accumulated more P when supplied with Al-P than when supplied with Fe-P. The P-efficient genotype 102 showed a significantly greater ability to deplete sparingly soluble P from the rhizosphere soil because of its greater biomass and higher P uptake compared with those of the P-inefficient genotype 105. In the solution experiment, the P-efficient genotype under low-P conditions developed dominant root morphological traits, and it showed more intensive rhizosphere acidification because of greater H(+) efflux, higher H(+)-ATPase activity, and greater exudation of carboxylates than the P-inefficient genotype. Thus, a combination of morphological and physiological mechanisms contributed to the genotypic variation in the utilization of different sparingly soluble P sources in B. napus.


Assuntos
Brassica napus/metabolismo , Genótipo , Fósforo/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/enzimologia , ATPases Translocadoras de Prótons/metabolismo
16.
Sci China Life Sci ; 53(6): 709-17, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20602274

RESUMO

To understand whether genotypic variation in acid phosphatase (APase) activity in rapeseed (Brassica napus L.) induced by phosphorus (P) deficiency has impact on P efficiency, soil APase activity in the rhizosphere for rapeseed P-efficient genotype 102 and P-inefficient genotype 105 was measured against organic and inorganic P sources in the pot experiment, and the activities of root-secreted APase and leaf intracellular APase were investigated in different P-starvation periods in the nutrient solution. Higher activity of root-secreted APase in B. napus was induced under low P conditions. However, P nutrition and P uptake efficiency of the plants supplied with organic P were not directly related to the activity of root-secreted APase due to several confounding factors affecting APase availability. The higher activity of leaf APase improved P remobilization in plants and played important roles in enhancing P use efficiency, shown by the significant correlation between leaf APase activity and P use efficiency in a rapeseed recombinant inbred population of 135 lines.


Assuntos
Fosfatase Ácida/metabolismo , Brassica napus/metabolismo , Fósforo/metabolismo , Brassica napus/enzimologia , Brassica napus/crescimento & desenvolvimento , Genótipo , Folhas de Planta/enzimologia , Raízes de Plantas/enzimologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA