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1.
Plant Dis ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549275

RESUMO

Cordyline fruticosa is a shrub plant, commonly used in landscape, and distributed in the tropical regions of southern China. In September 2022, anthracnose symptoms were found on this species in Nanning, Guangxi, China. The disease incidence was between 30% to 80% and disease severity was 10% to 30% in five surveyed planting areas. The symptoms initially appeared as small, round, brown spots on leaves. As the disease developed, the lesions turned gray-white with brown borders and yellow halos. Some spots coalesced into larger irregular shapes and even leading to leaf blight. Small segments of the diseased tissues (3×3 mm) were cut from the leaves, surface-sterilized by dipping in a 1% sodium hypochlorite solution for 1 min, rinsed three times with sterile distilled water, and plated on potato dextrose agar (PDA). These plates were incubated at 28°C in the dark for 5 days. Ten fungal isolates with similar morphology were consistently isolated from these diseased tissues. The colonies on PDA were initially white with sparse aerial mycelia and turned pale orange with abundant orange conidial masses on the center after 8 days of culture. The reverse color was pale orange. No sclerotia or setae were found in culture. Conidia were single-celled, hyaline, straight, cylindrical with round ends, and 12.2 to 17.8 µm long (mean 14.9 µm) and 3.9 to 7.3 µm wide (mean 4.8 µm, n=50). The morphological characteristics of these isolates were similar to the Colletotrichum cordylinicola (Sharma et al., 2014). Genomic DNA of two isolates Z3 and Z4 generated from monospore culture was extracted using a fungal DNA extraction kit (Solarbio, Beijing, China). Partial sequences of internal transcribed spacer (ITS), partial actin (ACT), chitin synthase (CHS-1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and beta-tubulin (TUB2) were amplified using the primer pairs ITS1/ITS4, ACT-512F/ACT-783R, CHS-79F/CHS-345R, GDF1/GDR1, and BT2A/BT2B (Lin et al., 2022), respectively. All the sequences (GenBank accession nos. OQ509909, OQ509910, OQ658690, OQ658691, and OK649310 to OK649314) showed 99% to 100% identity with those of C. cordylinicola in GenBank database. A phylogenetic tree based on concatenated sequences of ITS, ACT, CHS-1, TUB, and GAPDH using maximum likelihood analysis by MEGA X software revealed that Z3 and Z4 clade with reference strains of C. cordylinicola (OJX010226 and MK935473). Based on morphological observation and multi-gene sequence analysis, the isolates were identified as C. cordylinicola (Phoulivong et al., 2010). To assess their pathogenicity, conidial suspensions (106 conidia/ml) of C. cordylinicola were inoculated onto 10 healthy living leaves wounded by slight puncturing (10 µl/wounded spot). Control leaves were treated with sterile water. All inoculated and control plants were maintained under high relative humidity (~90%) and 28℃ in a climate chamber. After 8 days, all the inoculated leaves showed brown lesions resembling natural symptoms, whereas the control group remained symptom-free. The same fungus was re-isolated from the symptomatic leaves, thus completing Koch's postulates. C. cordylinicola is a species of the C. gloeosporioides complex (Weir et al., 2012). It has been reported to cause anthracnose on C. fruticosa in USA and Thailand (Phoulivong et al., 2010; Sharma et al., 2014). To our knowledge, this is the first report of C. cordylinicola causing anthracnose on C. fruticosa in China. Knowing the causal agent is essential to control the serious disease effectively.

2.
Ren Fail ; 45(1): 2194451, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36994793

RESUMO

AIM: Idiopathic membranous nephropathy (IMN) is a common type of nephrotic syndrome, and is associated with acute kidney injury (AKI). We investigated the association of multiple variables with AKI in patients with IMN. METHODS: The data of 187 patients with biopsy-proven IMN were examined. Renal outcome was defined as progression to end-stage renal disease (ESRD). Binary logistic regression and Kaplan-Meier's analysis were used for statistical analysis. RESULTS: During follow-up, 46 (24.6%) patients developed AKI. The incidence of AKI was greater in males than females (p < .01). The AKI group had higher uric acid, lower serum PLA2R antibody positive, and worse baseline kidney function (all p < .01). Most patients in the AKI group had stage I (71.74%) or stage II (21.74%). The AKI group had higher renal tubular injury score and chronicity index (both p < .05). Binary logistic regression indicated that uric acid and baseline estimated glomerular filtration rate (eGFR) were independent risk factors for AKI in patients with IMN (p < .05). The optimal cutoff value of serum uric acid for predicting AKI was 402.50 µmol/L and the baseline eGFR was 96.83 mL/min/1.73 m2. Kaplan-Meier's analysis showed that the cumulative renal survival rate was lower in the AKI group (p = .047). CONCLUSIONS: AKI increases the risk of poor prognosis in IMN patients and the high uric acid and low baseline eGFR were considered independent predictors for developing AKI in patients with IMN.


Assuntos
Injúria Renal Aguda , Glomerulonefrite Membranosa , Masculino , Feminino , Humanos , Glomerulonefrite Membranosa/complicações , Ácido Úrico , Rim , Prognóstico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/complicações , Estudos Retrospectivos
3.
Plant Physiol ; 185(1): 161-178, 2021 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-33631796

RESUMO

Regulation of floral transition and inflorescence development is crucial for plant reproductive success. FLOWERING LOCUS T (FT) is one of the central players in the flowering genetic regulatory network, whereas FLOWERING LOCUS D (FD), an interactor of FT and TERMINAL FLOWER 1 (TFL1), plays significant roles in both floral transition and inflorescence development. Here we show the genetic regulatory networks of floral transition and inflorescence development in Medicago truncatula by characterizing MtFTa1 and MtFDa and their genetic interactions with key inflorescence meristem (IM) regulators. Both MtFTa1 and MtFDa promote flowering; the double mutant mtfda mtfta1 does not proceed to floral transition. RNAseq analysis reveals that a broad range of genes involved in flowering regulation and flower development are up- or downregulated by MtFTa1 and/or MtFDa mutations. Furthermore, mutation of MtFDa also affects the inflorescence architecture. Genetic analyses of MtFDa, MtFTa1, MtTFL1, and MtFULc show that MtFDa is epistatic to MtFULc and MtTFL1 in controlling IM identity. Our results demonstrate that MtFTa1 and MtFDa are major flowering regulators in M. truncatula, and MtFDa is essential both in floral transition and secondary inflorescence development. The study will advance our understanding of the genetic regulation of flowering time and inflorescence development in legumes.


Assuntos
Inflorescência/anatomia & histologia , Inflorescência/crescimento & desenvolvimento , Inflorescência/genética , Magnoliopsida/crescimento & desenvolvimento , Magnoliopsida/genética , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/genética , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Genes de Plantas , Variação Genética , Genótipo , Mutação , Fenótipo , Plantas Geneticamente Modificadas
4.
Development ; 145(3)2018 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-29361570

RESUMO

Development of inflorescence architecture is controlled by genetic regulatory networks. TERMINAL FLOWER1 (TFL1), APETALA1 (AP1), LEAFY (LFY) and FRUITFULL (FUL) are core regulators for inflorescence development. To understand the regulation of compound inflorescence development, we characterized mutants of corresponding orthologous genes, MtTFL1, MtAP1, SINGLE LEAFLET1 (SGL1) and MtFULc, in Medicago truncatula, and analyzed expression patterns of these genes. Results indicate that MtTFL1, MtFULc, MtAP1 and SGL1 play specific roles in identity determination of primary inflorescence meristems, secondary inflorescence meristems, floral meristems and common primordia, respectively. Double mutation of MtTFL1 and MtFULc transforms compound inflorescences to simple flowers, whereas single mutation of MtTFL1 changes the inflorescence branching pattern from monopodial to sympodial. Double mutant mtap1sgl1 completely loses floral meristem identity. We conclude that inflorescence architecture in M. truncatula is controlled by spatiotemporal expression of MtTFL1, MtFULc, MtAP1 and SGL1 through reciprocal repression. Although this regulatory network shares similarity with the pea model, it has specificity in regulating inflorescence architecture in Mtruncatula This study establishes M. truncatula as an excellent genetic model for understanding compound inflorescence development in related legume crops.


Assuntos
Inflorescência/crescimento & desenvolvimento , Inflorescência/genética , Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Inflorescência/metabolismo , Medicago truncatula/metabolismo , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Microscopia Eletrônica de Varredura , Modelos Genéticos , Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , RNA de Plantas/genética , RNA de Plantas/metabolismo
5.
Plant Biotechnol J ; 17(3): 580-593, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30133139

RESUMO

Cell wall recalcitrance is the major challenge to improving saccharification efficiency in converting lignocellulose into biofuels. However, information regarding the transcriptional regulation of secondary cell wall biogenesis remains poor in switchgrass (Panicum virgatum), which has been selected as a biofuel crop in the United States. In this study, we present a combination of computational and experimental approaches to develop gene regulatory networks for lignin formation in switchgrass. To screen transcription factors (TFs) involved in lignin biosynthesis, we developed a modified method to perform co-expression network analysis using 14 lignin biosynthesis genes as bait (target) genes. The switchgrass lignin co-expression network was further extended by adding 14 TFs identified in this study, and seven TFs identified in previous studies, as bait genes. Six TFs (PvMYB58/63, PvMYB42/85, PvMYB4, PvWRKY12, PvSND2 and PvSWN2) were targeted to generate overexpressing and/or down-regulated transgenic switchgrass lines. The alteration of lignin content, cell wall composition and/or plant growth in the transgenic plants supported the role of the TFs in controlling secondary wall formation. RNA-seq analysis of four of the transgenic switchgrass lines revealed downstream target genes of the secondary wall-related TFs and crosstalk with other biological pathways. In vitro transactivation assays further confirmed the regulation of specific lignin pathway genes by four of the TFs. Our meta-analysis provides a hierarchical network of TFs and their potential target genes for future manipulation of secondary cell wall formation for lignin modification in switchgrass.


Assuntos
Redes Reguladoras de Genes/genética , Genes de Plantas/genética , Lignina/biossíntese , Panicum/genética , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/genética , Panicum/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética
6.
Proc Natl Acad Sci U S A ; 113(25): 6997-7002, 2016 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-27274062

RESUMO

Physical dormancy of seed is an adaptive trait that widely exists in higher plants. This kind of dormancy is caused by a water-impermeable layer that blocks water and oxygen from the surrounding environment and keeps embryos in a viable status for a long time. Most of the work on hardseededness has focused on morphological structure and phenolic content of seed coat. The molecular mechanism underlying physical dormancy remains largely elusive. By screening a large number of Tnt1 retrotransposon-tagged Medicago truncatula lines, we identified nondormant seed mutants from this model legume species. Unlike wild-type hard seeds exhibiting physical dormancy, the mature mutant seeds imbibed water quickly and germinated easily, without the need for scarification. Microscopic observations of cross sections showed that the mutant phenotype was caused by a dysfunctional palisade cuticle layer in the seed coat. Chemical analysis found differences in lipid monomer composition between the wild-type and mutant seed coats. Genetic and molecular analyses revealed that a class II KNOTTED-like homeobox (KNOXII) gene, KNOX4, was responsible for the loss of physical dormancy in the seeds of the mutants. Microarray and chromatin immunoprecipitation analyses identified CYP86A, a gene associated with cutin biosynthesis, as one of the downstream target genes of KNOX4 This study elucidated a novel molecular mechanism of physical dormancy and revealed a new role of class II KNOX genes. Furthermore, KNOX4-like genes exist widely in seed plants but are lacking in nonseed species, indicating that KNOX4 may have diverged from the other KNOXII genes during the evolution of seed plants.


Assuntos
Genes Homeobox , Genes de Plantas , Medicago/genética , Dormência de Plantas/genética , Sementes , Regulação da Expressão Gênica de Plantas , Medicago/embriologia , Mutação
7.
Proteomics ; 18(2)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29193783

RESUMO

Virus infection in plants involves necrosis, chlorosis, and mosaic. The M strain of cucumber mosaic virus (M-CMV) has six distinct symptoms: vein clearing, mosaic, chlorosis, partial green recovery, complete green recovery, and secondary mosaic. Chlorosis indicates the loss of chlorophyll which is highly abundant in plant leaves and plays essential roles in photosynthesis. Blue native/SDS-PAGE combined with mass spectrum was performed to detect the location of virus, and proteomic analysis of chloroplast isolated from virus-infected plants was performed to quantify the changes of individual proteins in order to gain a global view of the total chloroplast protein dynamics during the virus infection. Among the 438 proteins quantified, 33 showed a more than twofold change in abundance, of which 22 are involved in the light-dependent reactions and five in the Calvin cycle. The dynamic change of these proteins indicates that light-dependent reactions are down-accumulated, and the Calvin cycle was up-accumulated during virus infection. In addition to the proteins involved in photosynthesis, tubulin was up-accumulated in virus-infected plant, which might contribute to the autophagic process during plant infection. In conclusion, this extensive proteomic investigation on intact chloroplasts of virus-infected tobacco leaves provided some important novel information on chlorosis mechanisms induced by virus infection.


Assuntos
Cloroplastos/metabolismo , Marcação por Isótopo/métodos , Nicotiana/metabolismo , Doenças das Plantas/virologia , Proteômica/métodos , Cloroplastos/virologia , Cucumovirus/fisiologia , Eletroforese em Gel de Poliacrilamida/métodos , Perfilação da Expressão Gênica , Espectrometria de Massas , Eletroforese em Gel de Poliacrilamida Nativa/métodos , Folhas de Planta/metabolismo , Folhas de Planta/virologia , Nicotiana/virologia
8.
Biochem Biophys Res Commun ; 498(3): 395-401, 2018 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-29407169

RESUMO

Cucumber Mosaic Virus (CMV) has a small RNA genome that encodes a limited number of proteins, but can infect many plant species, including Arabidopsis thaliana and Nicotiana benthamiana. Virus proteins thus have multiple means of conferring their pathogenicity during the infection process. However, the pathogenic mechanism of CMV remains unclear. Here we discovered that the expression of the CMV movement protein (MP) in A. thaliana and N. benthamiana can suppress reactive oxygen species (ROS) production triggered by multiple pathogen-associated molecular patterns (PAMPs), such as bacteria-derived peptide flg22, elf18, and fungal-derived chitin. Transgenic Arabidopsis plants expressing the MP were compromised in flg22-induced immune activation and were more susceptible to Pseudomonas syringae pv. tomato (Pst) DC3000 hrcC- strain infection. Further analysis revealed that flg22-induced resistance gene expression was also compromised in MP transgenic plants. The CMV MP protein was previously reported to function in cell-to-cell movement processes, and our findings offer a new molecular mechanism for the CMV MP protein in suppression of host PAMP-triggered immune responses.


Assuntos
Arabidopsis/imunologia , Cucumovirus/imunologia , Nicotiana/imunologia , Moléculas com Motivos Associados a Patógenos/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal , Proteínas Virais/imunologia , Arabidopsis/genética , Arabidopsis/virologia , Cucumovirus/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/virologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/imunologia , Plantas Geneticamente Modificadas/virologia , Espécies Reativas de Oxigênio/imunologia , Nicotiana/genética , Nicotiana/virologia , Proteínas Virais/genética
9.
J Exp Bot ; 69(20): 4867-4880, 2018 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-30295903

RESUMO

Medicago flowering, like that of Arabidopsis, is promoted by vernalization and long days, but alternative mechanisms are predicted because Medicago lacks the key regulators CO and FLC. Three Medicago SOC1-like genes, including MtSOC1a, were previously implicated in flowering control, but no legume soc1 mutants with altered flowering were reported. Here, reverse transciption-quantitative PCR (RT-qPCR) indicated that the timing and magnitude of MtSOC1a expression was regulated by the flowering promoter FTa1, while in situ hybridization indicated that MtSOC1a expression increased in the shoot apical meristem during the floral transition. A Mtsoc1a mutant showed delayed flowering and short primary stems. Overexpression of MtSOC1a partially rescued the flowering of Mtsoc1a, but caused a dramatic increase in primary stem height, well before the transition to flowering. Internode cell length correlated with stem height, indicating that MtSOC1a promotes cell elongation in the primary stem. However, application of gibberellin (GA3) caused stem elongation in both the wild type and Mtsoc1a, indicating that the mutant was not defective in gibberellin responsiveness. These results indicate that MtSOC1a may function as a floral integrator gene and promotes primary stem elongation. Overall, this study suggests that apart from some conservation with the Arabidopsis flowering network, MtSOC1a has a novel role in regulating aspects of shoot architecture.


Assuntos
Flores/crescimento & desenvolvimento , Proteínas de Domínio MADS/genética , Medicago/crescimento & desenvolvimento , Medicago/genética , Proteínas de Plantas/genética , Caules de Planta/crescimento & desenvolvimento , Sequência de Aminoácidos , Arabidopsis/genética , Flores/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Domínio MADS/química , Proteínas de Domínio MADS/metabolismo , Medicago/metabolismo , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Caules de Planta/genética , Alinhamento de Sequência
10.
Plant Biotechnol J ; 15(6): 688-697, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27862852

RESUMO

Transgenic Panicum virgatum L. silencing (KD) or overexpressing (OE) specific genes or a small RNA (GAUT4-KD, miRNA156-OE, MYB4-OE, COMT-KD and FPGS-KD) was grown in the field and aerial tissue analysed for biofuel production traits. Clones representing independent transgenic lines were established and senesced tissue was sampled after year 1 and 2 growth cycles. Biomass was analysed for wall sugars, recalcitrance to enzymatic digestibility and biofuel production using separate hydrolysis and fermentation. No correlation was found between plant carbohydrate content and biofuel production pointing to overriding structural and compositional elements that influence recalcitrance. Biomass yields were greater for all lines in the second year as plants establish in the field and standard amounts of biomass analysed from each line had more glucan, xylan and less ethanol (g/g basis) in the second- versus the first-year samples, pointing to a broad increase in tissue recalcitrance after regrowth from the perennial root. However, biomass from second-year growth of transgenics targeted for wall modification, GAUT4-KD, MYB4-OE, COMT-KD and FPGS-KD, had increased carbohydrate and ethanol yields (up to 12% and 21%, respectively) compared with control samples. The parental plant lines were found to have a significant impact on recalcitrance which can be exploited in future strategies. This summarizes progress towards generating next-generation bio-feedstocks with improved properties for microbial and enzymatic deconstruction, while providing a comprehensive quantitative analysis for the bioconversion of multiple plant lines in five transgenic strategies.


Assuntos
Panicum/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Biocombustíveis , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Panicum/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética
11.
Plant Cell ; 26(2): 650-64, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24585835

RESUMO

The Medicago truncatula WUSCHEL-related homeobox (WOX) gene, STENOFOLIA (STF), plays a key role in leaf blade outgrowth by promoting cell proliferation at the adaxial-abaxial junction. STF functions primarily as a transcriptional repressor, but the underlying molecular mechanism is unknown. Here, we report the identification of a protein interaction partner and a direct target, shedding light on the mechanism of STF function. Two highly conserved motifs in the C-terminal domain of STF, the WUSCHEL (WUS) box and the STF box, cooperatively recruit TOPLESS (Mt-TPL) family corepressors, and this recruitment is required for STF function, as deletion of these two domains (STFdel) impaired blade outgrowth whereas fusing Mt-TPL to STFdel restored function. The homeodomain motif is required for direct repression of ASYMMETRIC LEAVES2 (Mt-AS2), silencing of which partially rescues the stf mutant phenotype. STF and LAMINALESS1 (LAM1) are functional orthologs. A single amino acid (Asn to Ile) substitution in the homeodomain abolished the repression of Mt-AS2 and STF's ability to complement the lam1 mutant of Nicotiana sylvestris. Our data together support a model in which STF recruits corepressors to transcriptionally repress its targets during leaf blade morphogenesis. We propose that recruitment of TPL/TPL-related proteins may be a common mechanism in the repressive function of modern/WUS clade WOX genes.


Assuntos
Medicago truncatula/crescimento & desenvolvimento , Medicago truncatula/metabolismo , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/metabolismo , Proteínas Repressoras/metabolismo , Sequência de Aminoácidos , Sequência Conservada , Inativação Gênica , Dados de Sequência Molecular , Fenótipo , Proteínas de Plantas/química , Regiões Promotoras Genéticas/genética , Ligação Proteica , Estrutura Terciária de Proteína , Relação Estrutura-Atividade , Nicotiana/metabolismo
12.
Plant Cell ; 26(4): 1464-1479, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24781113

RESUMO

Class I KNOTTED-like homeobox (KNOXI) genes are critical for the maintenance of the shoot apical meristem. The expression domain of KNOXI is regulated by ASYMMETRIC LEAVES1/ROUGHSHEATH2/PHANTASTICA (ARP) genes, which are associated with leaf morphology. In the inverted repeat-lacking clade (IRLC) of Fabaceae, the orthologs of LEAFY (LFY) function in place of KNOXI to regulate compound leaf development. Here, we characterized loss-of-function mutants of ARP (PHAN) and SHOOTMERISTEMLESS (STM)- and BREVIPEDICELLUS (BP)-like KNOXI in the model IRLC legume species Medicago truncatula. The function of ARP genes is species specific. The repression of STM/BP-like KNOXI genes in leaves is not mediated by PHAN, and no suppression of PHAN by STM/BP-like KNOXI genes was observed either, indicating that STM/BP-like KNOXI genes are uncoupled from PHAN in M. truncatula. Furthermore, comparative analyses of phenotypic output in response to ectopic expression of KNOXI and the M. truncatula LFY ortholog, SINGLE LEAFLET1 (SGL1), reveal that KNOXI and SGL1 regulate parallel pathways in leaf development. We propose that SGL1 probably functions in a stage-specific manner in the regulation of the indeterminate state of developing leaves in M. truncatula.

13.
Plant J ; 81(3): 480-92, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25492397

RESUMO

The Medicago truncatula WOX gene, STENOFOLIA (STF), and its orthologs in Petunia, pea, and Nicotiana sylvestris are required for leaf blade outgrowth and floral organ development as demonstrated by severe phenotypes in single mutants. But the Arabidopsis wox1 mutant displays a narrow leaf phenotype only when combined with the prs/wox3 mutant. In maize and rice, WOX3 homologs are major regulators of leaf blade development. Here we investigated the role of WOX3 in M. truncatula development by isolating the lfl/wox3 loss-of-function mutant and performing genetic crosses with the stf mutant. Lack of WOX3 function in M. truncatula leads to a loose-flower (lfl) phenotype, where defects are observed in sepal and petal development, but leaf blades are apparently normal. The stf lfl double mutant analysis revealed that STF and LFL act mainly independently with minor redundant functions in flower development, but LFL has no obvious role in leaf blade outgrowth in M. truncatula on its own or in combination with STF. Interestingly, LFL acts as a transcriptional repressor by recruiting TOPLESS in the same manner as STF does, and can substitute for STF function in leaf blade and flower development if expressed under the STF promoter. STF also complements the lfl mutant phenotype in the flower if expressed under the LFL promoter. Our data suggest that the STF/WOX1 and LFL/WOX3 genes of M. truncatula employ a similar mechanism of action in organizing cell proliferation for lateral outgrowth but may have evolved different cis elements to acquire distinct functions.


Assuntos
Proteínas de Homeodomínio/fisiologia , Medicago truncatula/crescimento & desenvolvimento , Proteínas de Plantas/fisiologia , Clonagem Molecular , Flores/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Medicago truncatula/genética , Medicago truncatula/metabolismo , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
14.
J Exp Bot ; 67(6): 1649-62, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26896851

RESUMO

Almost all C4 plants require the co-ordination of the adjacent and fully differentiated cell types, mesophyll (M) and bundle sheath (BS). The C4 photosynthetic pathway operates through two distinct subtypes based on how malate is decarboxylated in BS cells; through NAD-malic enzyme (NAD-ME) or NADP-malic enzyme (NADP-ME). The diverse or unique cell-specific molecular features of M and BS cells from separate C4 subtypes of independent lineages remain to be determined. We here provide an M/BS cell type-specific transcriptome data set from the monocot NAD-ME subtype switchgrass (Panicum virgatum). A comparative transcriptomics approach was then applied to compare the M/BS mRNA profiles of switchgrass, monocot NADP-ME subtype C4 plants maize and Setaria viridis, and dicot NAD-ME subtype Cleome gynandra. We evaluated the convergence in the transcript abundance of core components in C4 photosynthesis and transcription factors to establish Kranz anatomy, as well as gene distribution of biological functions, in these four independent C4 lineages. We also estimated the divergence between NAD-ME and NADP-ME subtypes of C4 photosynthesis in the two cell types within C4 species, including differences in genes encoding decarboxylating enzymes, aminotransferases, and metabolite transporters, and differences in the cell-specific functional enrichment of RNA regulation and protein biogenesis/homeostasis. We suggest that C4 plants of independent lineages in both monocots and dicots underwent convergent evolution to establish C4 photosynthesis, while distinct C4 subtypes also underwent divergent processes for the optimization of M and BS cell co-ordination. The comprehensive data sets in our study provide a basis for further research on evolution of C4 species.


Assuntos
Diferenciação Celular , Panicum/citologia , Panicum/genética , Fotossíntese/genética , Filogenia , Transcriptoma/genética , Transporte Biológico , Carbono/metabolismo , Separação Celular , Mapeamento Cromossômico , Regulação da Expressão Gênica de Plantas , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização In Situ , Malato Desidrogenase/metabolismo , Células do Mesofilo/metabolismo , Modelos Biológicos , Folhas de Planta/genética , Proteínas de Plantas/metabolismo , Feixe Vascular de Plantas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
15.
Plant Cell ; 25(11): 4342-61, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24285795

RESUMO

It is necessary to overcome recalcitrance of the biomass to saccharification (sugar release) to make switchgrass (Panicum virgatum) economically viable as a feedstock for liquid biofuels. Lignin content correlates negatively with sugar release efficiency in switchgrass, but selecting the right gene candidates for engineering lignin biosynthesis in this tetraploid outcrossing species is not straightforward. To assist this endeavor, we have used an inducible switchgrass cell suspension system for studying lignin biosynthesis in response to exogenous brassinolide. By applying a combination of protein sequence phylogeny with whole-genome microarray analyses of induced cell cultures and developing stem internode sections, we have generated a list of candidate monolignol biosynthetic genes for switchgrass. Several genes that were strongly supported through our bioinformatics analysis as involved in lignin biosynthesis were confirmed by gene silencing studies, in which lignin levels were reduced as a result of targeting a single gene. However, candidate genes encoding enzymes involved in the early steps of the currently accepted monolignol biosynthesis pathway in dicots may have functionally redundant paralogues in switchgrass and therefore require further evaluation. This work provides a blueprint and resources for the systematic genome-wide study of the monolignol pathway in switchgrass, as well as other C4 monocot species.


Assuntos
Genômica/métodos , Lignina/biossíntese , Panicum/genética , Panicum/metabolismo , Vias Biossintéticas/genética , Técnicas de Cultura de Células , Clonagem Molecular , Análise por Conglomerados , Enzimas/genética , Enzimas/metabolismo , Regulação da Expressão Gênica de Plantas , Inativação Gênica , Lignina/genética , Anotação de Sequência Molecular , Dados de Sequência Molecular , Panicum/citologia , Filogenia , Plantas Geneticamente Modificadas
16.
Clin Nephrol ; 84(5): 262-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26396095

RESUMO

OBJECTIVE: To evaluate the efficacy and safety of calcitriol in the prevention and treatment of glucocorticoid-induced osteoporosis. METHODS: 66 patients treated with glucocorticoids (GC) for primary nephrotic syndrome (NS) were randomly assigned to 3 groups. Groups were designated as follows: calcitriol alone (n = 22), calcitriol plus calcium carbonate (n = 23), or calcium carbonate alone (n = 21). Serum markers of bone metabolism and bone mineral density (BMD) were tested at 3 different time points: the initiation of GC treatment (baseline), 12 weeks, and 24 weeks after the initiation of treatment. RESULTS: Levels of serum 25-hydroxy vitamin D, serum osteocalcin, and total serum collagen type N-terminal extension of the peptide were significantly decreased following GC therapy (p < 0.05). ß-collagen serum-specific sequences were significantly increased following GC therapy. The above-mentioned changes were less dramatic in patients treated with calcitriol, although the differences were significant (p < 0.05). Changes in serum levels of calcium, phosphorus, alkaline phosphatase, and parathyroid hormone (PTH) were not significant. 24 weeks after the initiation of treatment, BMD of the lumbar spine and femoral bone significantly decreased in all of 3 groups. However, patients who received calcitriol had significantly higher BMD of the lumbar spine than patients who received calcium carbonate alone (calcitriol plus calcium carbonate vs. calcium carbonate alone: 0.82 ± 0.19 g/cm2 vs. 0.62 ± 0.23 g/cm2 p < 0.05; calcitriol vs. calcium carbonate alone 0.805 ± 0.203 g/cm2 vs. 0.615 ± 0.225 g/cm2 p < 0.05), respectively. No serious adverse events were observed. CONCLUSION: Calcitriol may be more effective than calcium carbonate in preventing and treating GC-induced osteoporosis in patients with NS.


Assuntos
Calcitriol/uso terapêutico , Glucocorticoides/efeitos adversos , Síndrome Nefrótica/tratamento farmacológico , Osteoporose/tratamento farmacológico , Adulto , Fosfatase Alcalina/sangue , Densidade Óssea/efeitos dos fármacos , Calcitriol/efeitos adversos , Carbonato de Cálcio/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Osteoporose/induzido quimicamente , Hormônio Paratireóideo/sangue , Vitamina D/análogos & derivados , Vitamina D/sangue
17.
PLoS One ; 19(5): e0302462, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753836

RESUMO

Fruit shape is an important character of watermelon. And the compositions of rhizospheric and endophytic microorganisms of watermelon with different fruit shape also remains unclear. To elucidate the biological mechanism of watermelon fruit shape formations, the rhizospheric and endophytic microbial community compositions between oval (OW) and circular watermelons (CW) were analyzed. The results showed that except of the rhizospheric bacterial richness (P < 0.05), the rhizospheric and endophytic microbial (bacterial and fungal) diversity were not statistically significant between OW and CW (P > 0.05). However, the endophytic microbial (bacterial and fungal) compositions were significantly different. Firstly, Bacillus, Rhodanobacter, Cupriavidus, Luteimonas, and Devosia were the unique soil dominant bacterial genera in rhizospheres of circular watermelon (CW); In contrast, Nocardioides, Ensifer, and Saccharomonospora were the special soil dominant bacterial genera in rhizospheres of oval watermelons (OW); Meanwhile, Cephalotrichum, Neocosmospora, Phialosimplex, and Papulaspora were the unique soil dominant fungal genera in rhizospheres of circular watermelon (CW); By contrast, Acremonium, Cladosporium, Cryptococcus_f__Tremellaceae, Sodiomyces, Microascus, Conocybe, Sporidiobolus, and Acremonium were the unique soil dominant fungal genera in rhizospheres of oval watermelons (OW). Additionally, Lechevalieria, Pseudorhodoferax, Pseudomonas, Massilia, Flavobacterium, Aeromicrobium, Stenotrophomonas, Pseudonocardia, Novosphingobium, Melittangium, and Herpetosiphon were the unique dominant endophytic bacterial genera in stems of CW; In contrast, Falsirhodobacter, Kocuria, and Kineosporia were the special dominant endophytic genera in stems of OW; Moreover, Lectera and Fusarium were the unique dominant endophytic fungal genera in stems of CW; By contrast, Cercospora only was the special dominant endophytic fungal genus in stems of OW. All above results suggested that watermelons with different fruit shapes exactly recruited various microorganisms in rhizospheres and stems. Meanwhile, the enrichments of the different rhizosphric and endophytic microorganisms could be speculated in relating to watermelon fruit shapes formation.


Assuntos
Bactérias , Citrullus , Endófitos , Frutas , Fungos , Rizosfera , Microbiologia do Solo , Citrullus/microbiologia , Endófitos/genética , Frutas/microbiologia , Bactérias/genética , Bactérias/classificação , Bactérias/isolamento & purificação , Fungos/genética , Fungos/classificação , Fungos/isolamento & purificação , Microbiota/genética
18.
Nanoscale ; 16(26): 12550-12558, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38884386

RESUMO

Photocatalytic reduction of CO2 to chemical fuels is attractive for solving both the greenhouse effect and the energy crisis, but the key challenge is to design and synthesize photocatalysts with remarkable performance under visible light irradiation. Efficient catalytic carbon dioxide reduction (CO2RR) with light is considered a promising sustainable and clean approach to solve environmental problems. Herein, we found a new photocatalyst ([Mn(en)2]6[V12B18O54(OH)6]) (abbreviated as Mn6V12) based on the modifiability of polyoxometalates, in which Mn acts as a modifying unit to efficiently reduce CO2 to CO and effectively inhibit the hydrogen precipitation reaction. This Mn modified polyoxometalate catalyst has a maximum CO generation rate of 4625.0 µmol g-1 h-1 and a maximum H2 generation rate of 499.6 µmol g-1 h-1, with a selectivity of 90.3% for CO generation and 9.7% for H2 generation. This polyoxometalate photocatalyst can effectively reduce CO and inhibit the hydrogen precipitation reaction. It provides a new idea for the efficient photocatalytic carbon dioxide reduction (CO2RR) with polyoxometalate catalysts.

19.
PeerJ ; 12: e17266, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38650643

RESUMO

Objective: Whether serum uric acid (SUA) at baseline could been identiûed as a risk factor for progression in IgA nephropathy (IgAN) patients remains unclear, therefore, long- term SUA control levels must be monitored. We aimed to investigate the relevant factors affecting time-averaged SUA (TA-SUA) and to assess the prognostic value of TA-SUA in IgAN. Methods: This retrospective study included 152 patients with IgAN. The relationships between TA-SUA and clinicopathological features and renal outcomes (defined as the doubling of the baseline serum creatinine level or end-stage renal disease) were analyzed in groups divided by quartiles of TA-SUA levels, the presence of hyperuricemia, and sex. Results: Patients with high TA-SUA levels had higher levels of baseline SUA, blood urea nitrogen (BUN), triglycerides, serum C3 and serum C4 and were more likely to be male and have hypertension, proteinuria, poor renal function, and pathological injuries including high grades of tubular atrophy/interstitial fibrosis (T1-T2). These patients had a poorer prognosis compared with patients with low TA-SUA levels. The TA-SUA level was positively correlated with baseline age and BUN, triglycerides, serum C3, and serum C4 levels, and negatively correlated with baseline eGFR. Survival curve analysis indicated that persistent hyperuricemia was associated with significantly poorer renal outcomes than normo-uricemia in both men and women. The TA-SUA level also was an independent predictor of renal outcome in patients with IgAN, with optimal cutoû values of 451.38 µmol/L (area under the curve (AUC) = 0.934) for men and 492.83 µmol/L (AUC = 0.768) for women. Conclusions: The TA-SUA level is associated with triglyceride level, complement component levels, renal function, and pathological severity of IgAN, and it may be a prognostic indicator in male and female patients with IgAN.


Assuntos
Glomerulonefrite por IGA , Ácido Úrico , Humanos , Glomerulonefrite por IGA/sangue , Glomerulonefrite por IGA/patologia , Masculino , Feminino , Ácido Úrico/sangue , Estudos Retrospectivos , Adulto , Prognóstico , Hiperuricemia/sangue , Pessoa de Meia-Idade , Progressão da Doença , Fatores de Risco , Falência Renal Crônica/sangue
20.
Anal Biochem ; 440(1): 18-22, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23660014

RESUMO

We report a biosensor based on surface plasmon resonance (SPR) for the selective detection of maize chlorotic mottle virus (MCMV). 11-Mercaptoundecanoic acid was applied on a gold surface to form a self-assembled monolayer, and a layer of anti-MCMV antibody was crosslinked on the surface for specific recognition of MCMV. The effects of coupling reaction time and antibody concentration on detection sensitivity were studied. The coverage mass change is a function of the concentration of MCMV with a dynamic range from 1 to 1000 ppb. The detection limit is approximately 1 ppb, which is approximately two orders of magnitude higher than that of the existing enzyme-linked immunosorbent assay (ELISA) method. The developed SPR sensor showed highly specific recognition for both purified MCMV and crude extracts from real-world samples.


Assuntos
Técnicas Biossensoriais/métodos , Ácidos Graxos/análise , Compostos de Sulfidrila/análise , Ressonância de Plasmônio de Superfície/métodos , Tombusviridae/isolamento & purificação , Zea mays/virologia , Ensaio de Imunoadsorção Enzimática , Sensibilidade e Especificidade
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