Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 14 de 14
Filtrar
1.
Proc Natl Acad Sci U S A ; 118(41)2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34611019

RESUMO

Cytotoxic CD8 T lymphocytes play a central role in the tissue destruction of many autoimmune disorders. In type 1 diabetes (T1D), insulin and its precursor preproinsulin are major self-antigens targeted by T cells. We comprehensively examined preproinsulin specificity of CD8 T cells obtained from pancreatic islets of organ donors with and without T1D and identified epitopes throughout the entire preproinsulin protein and defective ribosomal products derived from preproinsulin messenger RNA. The frequency of preproinsulin-reactive T cells was significantly higher in T1D donors than nondiabetic donors and also differed by individual T1D donor, ranging from 3 to over 40%, with higher frequencies in T1D organ donors with HLA-A*02:01. Only T cells reactive to preproinsulin-related peptides isolated from T1D donors demonstrated potent autoreactivity. Reactivity to similar regions of preproinsulin was also observed in peripheral blood of a separate cohort of new-onset T1D patients. These findings have important implications for designing antigen-specific immunotherapies and identifying individuals that may benefit from such interventions.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Precursores de Proteínas/imunologia , Adolescente , Adulto , Autoantígenos/imunologia , Autoimunidade/imunologia , Criança , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 1/terapia , Feminino , Antígeno HLA-A2 , Humanos , Imunoterapia/métodos , Ilhotas Pancreáticas/citologia , Masculino , Adulto Jovem
2.
J Immunol ; 200(4): 1504-1512, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29311365

RESUMO

The autoimmune condition is a primary obstacle to inducing tolerance in type 1 diabetes patients receiving allogeneic pancreas transplants. It is unknown how autoreactive T cells that recognize self-MHC molecules contribute to MHC-disparate allograft rejection. In this report, we show the presence and accumulation of dual-reactive, that is autoreactive and alloreactive, T cells in C3H islet allografts that were transplanted into autoimmune diabetic NOD mice. Using high-throughput sequencing, we discovered that T cells prevalent in allografts share identical TCRs with autoreactive T cells present in pancreatic islets. T cells expressing TCRs that are enriched in allograft lesions recognized C3H MHC molecules, and five of six cell lines expressing these TCRs were also reactive to NOD islet cells. These results reveal the presence of autoreactive T cells that mediate cross-reactive alloreactivity, and indicate a requirement for regulating such dual-reactive T cells in tissue replacement therapies given to autoimmune individuals.


Assuntos
Aloenxertos/imunologia , Autoantígenos/imunologia , Rejeição de Enxerto/imunologia , Transplante das Ilhotas Pancreáticas/imunologia , Animais , Diabetes Mellitus Tipo 1/cirurgia , Camundongos , Camundongos Endogâmicos NOD , Receptores de Antígenos de Linfócitos T/imunologia
3.
J Immunol ; 199(7): 2279-2290, 2017 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-28827283

RESUMO

Sarcoidosis is a granulomatous disease that primarily affects the lungs and is characterized by an accumulation of CD4+ T cells in the bronchoalveolar lavage (BAL). Previous work has indicated that HLA-DRB1*03:01+ (DR3+) patients diagnosed with the acute form of the disease, Löfgren's syndrome (LS), have an accumulation of CD4+ T cells bearing TCRs using TRAV12-1 (formerly AV2S3). However, the importance of these α-chains in disease pathogenesis and the paired TCRß-chain remains unknown. This study aimed to identify expanded αßTCR pairs expressed on CD4+ T cells derived from the BAL of DR3+ LS patients. Using a deep-sequencing approach, we determined TCRα- and TCRß-chain usage, as well as αßTCR pairs expressed on BAL CD4+ T cells from LS patients. TRAV12-1 and TRBV2 (formerly BV22) were the most expanded V region gene segments in DR3+ LS patients relative to control subjects, and TRAV12-1 and TRBV2 CDR3 motifs were shared among multiple DR3+ LS patients. When assessing αßTCR pairing, TRAV12-1 preferentially paired with TRBV2, and these TRAV12-1/TRBV2 TCRs displayed CDR3 homology. These findings suggest that public CD4+ TCR repertoires exist among LS patients and that these T cells are recognizing the putative sarcoidosis-associated Ag(s) in the context of DR3.


Assuntos
Líquido da Lavagem Broncoalveolar/citologia , Pulmão/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Sarcoidose Pulmonar/imunologia , Doença Aguda , Adulto , Idoso , Líquido da Lavagem Broncoalveolar/imunologia , Linfócitos T CD4-Positivos/imunologia , Feminino , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/genética , Membro 25 de Receptores de Fatores de Necrose Tumoral/imunologia
4.
Front Immunol ; 14: 1276255, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908349

RESUMO

Gold nanoparticles (GNPs) have been used in the development of novel therapies as a way of delivery of both stimulatory and tolerogenic peptide cargoes. Here we report that intradermal injection of GNPs loaded with the proinsulin peptide C19-A3, in patients with type 1 diabetes, results in recruitment and retention of immune cells in the skin. These include large numbers of clonally expanded T-cells sharing the same paired T-cell receptors (TCRs) with activated phenotypes, half of which, when the TCRs were re-expressed in a cell-based system, were confirmed to be specific for either GNP or proinsulin. All the identified gold-specific clones were CD8+, whilst proinsulin-specific clones were both CD8+ and CD4+. Proinsulin-specific CD8+ clones had a distinctive cytotoxic phenotype with overexpression of granulysin (GNLY) and KIR receptors. Clonally expanded antigen-specific T cells remained in situ for months to years, with a spectrum of tissue resident memory and effector memory phenotypes. As the T-cell response is divided between targeting the gold core and the antigenic cargo, this offers a route to improving resident memory T-cells formation in response to vaccines. In addition, our scRNAseq data indicate that focusing on clonally expanded skin infiltrating T-cells recruited to intradermally injected antigen is a highly efficient method to enrich and identify antigen-specific cells. This approach has the potential to be used to monitor the intradermal delivery of antigens and nanoparticles for immune modulation in humans.


Assuntos
Diabetes Mellitus Tipo 1 , Nanopartículas Metálicas , Humanos , Autoantígenos , Proinsulina/genética , Ouro , Injeções Intradérmicas , Análise da Expressão Gênica de Célula Única , Peptídeos/genética , Receptores de Antígenos de Linfócitos T/genética
5.
Bio Protoc ; 11(2): e3883, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33732772

RESUMO

Immune tolerance and response are both largely driven by the interactions between the major histocompatibility complex (MHC) expressed by antigen presenting cells (APCs), T-cell receptors (TCRs) on T-cells, and their cognate antigens. Disordered interactions cause the pathogenesis of autoimmune diseases such as type 1 diabetes. Therefore, the identification of antigenic epitopes of autoreactive T-cells leads to important advances in therapeutics and biomarkers. Next-generation sequencing methods allow for the rapid identification of thousands of TCR clonotypes from single T-cells, and thus there is a need to determine cognate antigens for identified TCRs. This protocol describes a reporter system of T-cell activation where the fluorescent reporter protein ZsGreen-1 is driven by nuclear factor of activated T-cells (NFAT) signaling and read by flow cytometry. Reporter T-cells also constitutively express additional pairs of fluorescent proteins as identifiers, allowing for multiplexing of up to eight different reporter T-cell lines simultaneously, each expressing a different TCR of interest and distinguishable by flow cytometry. Once TCR expression cell lines are made they can be used indefinitely for making new T-cell lines with just one transduction step. This multiplexing system permits screening numbers of TCR-antigen interactions that would otherwise be impractical, can be used in a variety of contexts (i.e., screening individual antigens or antigen pools), and can be applied to study any T-cell-MHC-antigen trimolecular interaction.

6.
Front Endocrinol (Lausanne) ; 12: 622647, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33841327

RESUMO

Proinsulin is an abundant protein that is selectively expressed by pancreatic beta cells and has been a focus for development of antigen-specific immunotherapies for type 1 diabetes (T1D). In this study, we sought to comprehensively evaluate reactivity to preproinsulin by CD4 T cells originally isolated from pancreatic islets of organ donors having T1D. We analyzed 187 T cell receptor (TCR) clonotypes expressed by CD4 T cells obtained from six T1D donors and determined their response to 99 truncated preproinsulin peptide pools, in the presence of autologous B cells. We identified 14 TCR clonotypes from four out of the six donors that responded to preproinsulin peptides. Epitopes were found across all of proinsulin (insulin B-chain, C-peptide, and A-chain) including four hot spot regions containing peptides commonly targeted by TCR clonotypes derived from multiple T1D donors. Of importance, these hot spots overlap with peptide regions to which CD4 T cell responses have previously been detected in the peripheral blood of T1D patients. The 14 TCR clonotypes recognized proinsulin peptides presented by various HLA class II molecules, but there was a trend for dominant restriction with HLA-DQ, especially T1D risk alleles DQ8, DQ2, and DQ8-trans. The characteristics of the tri-molecular complex including proinsulin peptide, HLA-DQ molecule, and TCR derived from CD4 T cells in islets, provides an essential basis for developing antigen-specific biomarkers as well as immunotherapies.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Diabetes Mellitus Tipo 1/metabolismo , Insulina/farmacologia , Ilhotas Pancreáticas/efeitos dos fármacos , Precursores de Proteínas/farmacologia , Linfócitos T CD4-Positivos/metabolismo , Epitopos/metabolismo , Humanos , Ilhotas Pancreáticas/metabolismo , Doadores de Tecidos
7.
Front Immunol ; 12: 668680, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113344

RESUMO

Hybrid Insulin Peptides (HIPs), which consist of insulin fragments fused to other peptides from ß-cell secretory granule proteins, are CD4 T cell autoantigens in type 1 diabetes (T1D). We have studied HIPs and HIP-reactive CD4 T cells extensively in the context of the non-obese diabetic (NOD) mouse model of autoimmune diabetes and have shown that CD4 T cells specific for HIPs are major contributors to disease pathogenesis. Additionally, in the human context, HIP-reactive CD4 T cells can be found in the islets and peripheral blood of T1D patients. Here, we performed an in-depth characterization of the CD4 T cell response to a C-peptide/C-peptide HIP (HIP11) in human T1D. We identified the TCR expressed by the previously-reported HIP11-reactive CD4 T cell clone E2, which was isolated from the peripheral blood of a T1D patient, and determined that it recognizes HIP11 in the context of HLA-DQ2. We also identified a HIP11-specific TCR directly in the islets of a T1D donor and demonstrated that this TCR recognizes a different minimal epitope of HIP11 presented by HLA-DQ8. We generated and tested an HLA-DQ2 tetramer loaded with HIP11 that will enable direct ex vivo interrogation of CD4 T cell responses to HIP11 in human patients and control subjects. Using mass spectrometric analysis, we confirmed that HIP11 is present in human islets. This work represents an important step in characterizing the role of CD4 T cell responses to HIPs in human T1D.


Assuntos
Autoantígenos/imunologia , Peptídeo C/imunologia , Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Autoantígenos/metabolismo , Peptídeo C/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Diabetes Mellitus Tipo 1/sangue , Epitopos , Feminino , Antígenos HLA-DQ/imunologia , Humanos , Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Células K562 , Masculino , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo
8.
J Clin Invest ; 131(9)2021 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-33630763

RESUMO

Discovering dominant epitopes for T cells, particularly CD4+ T cells, in human immune-mediated diseases remains a significant challenge. Here, we used bronchoalveolar lavage (BAL) cells from HLA-DP2-expressing patients with chronic beryllium disease (CBD), a debilitating granulomatous lung disorder characterized by accumulations of beryllium-specific (Be-specific) CD4+ T cells in the lung. We discovered lung-resident CD4+ T cells that expressed a disease-specific public CDR3ß T cell receptor motif and were specific to Be-modified self-peptides derived from C-C motif ligand 4 (CCL4) and CCL3. HLA-DP2-CCL/Be tetramer staining confirmed that these chemokine-derived peptides represented major antigenic targets in CBD. Furthermore, Be induced CCL3 and CCL4 secretion in the lungs of mice and humans. In a murine model of CBD, the addition of LPS to Be oxide exposure enhanced CCL4 and CCL3 secretion in the lung and significantly increased the number and percentage of CD4+ T cells specific for the HLA-DP2-CCL/Be epitope. Thus, we demonstrate a direct link between Be-induced innate production of chemokines and the development of a robust adaptive immune response to those same chemokines presented as Be-modified self-peptides, creating a cycle of innate and adaptive immune activation.


Assuntos
Beriliose/imunologia , Berílio/toxicidade , Linfócitos T CD4-Positivos/imunologia , Quimiocina CCL3/imunologia , Quimiocina CCL4/imunologia , Pulmão/imunologia , Animais , Antígenos , Beriliose/genética , Beriliose/patologia , Linfócitos T CD4-Positivos/patologia , Quimiocina CCL3/genética , Quimiocina CCL4/genética , Doença Crônica , Feminino , Cadeias beta de HLA-DP/genética , Cadeias beta de HLA-DP/imunologia , Humanos , Imunidade Inata/efeitos dos fármacos , Imunidade Inata/genética , Pulmão/patologia , Masculino , Camundongos
9.
Front Immunol ; 11: 633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328071

RESUMO

Recent advancements in single cell sequencing technologies allow for identification of numerous immune-receptors expressed by T cells such as tumor-specific and autoimmune T cells. Determining antigen specificity of those cells holds immense therapeutic promise. Therefore, the purpose of this study was to develop a method that can efficiently test antigen reactivity of multiple T cell receptors (TCRs) with limited cost, time, and labor. Nuclear factor of activated T cells (NFAT) is a transcription factor involved in producing cytokines and is often utilized as a reporter system for T cell activation. Using a NFAT-based fluorescent reporter system, we generated T-hybridoma cell lines that express intensely fluorescent proteins in response to antigen stimulation and constitutively express additional fluorescent proteins, which serve as identifiers of each T-hybridoma expressing a unique TCR. This allows for the combination of multiple T-hybridoma lines within a single reaction. Sensitivity to stimulation is not decreased by adding fluorescent proteins or multiplexing T cells. In multiplexed reactions, response by one cell line does not induce response in others, thus preserving specificity. This multiplex assay system will be a useful tool for antigen discovery research in a variety of contexts, including using combinatorial peptide libraries to determine T cell epitopes.


Assuntos
Complexo CD3/metabolismo , Linfócitos T CD4-Positivos/imunologia , Imunoensaio/métodos , Receptores de Antígenos de Linfócitos T/metabolismo , Retroviridae/genética , Animais , Epitopos de Linfócito T/imunologia , Genes Reporter , Vetores Genéticos , Hibridomas , Imunização , Ativação Linfocitária , Camundongos , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Transdução de Sinais
10.
J Immunol Methods ; 462: 65-73, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30165064

RESUMO

Immortalized T cells such as T cell hybridomas, transfectomas, and transductants are useful tools to study tri-molecular complexes consisting of peptide, MHC, and T cell receptor (TCR) molecules. These cells have been utilized for antigen discovery studies for decades due to simplicity and rapidness of growing cells. However, responsiveness to antigen stimulation is typically less sensitive compared to primary T cells, resulting in occasional false negative outcomes especially for TCRs having low affinity to a peptide-MHC complex (pMHC). To overcome this obstacle, we genetically engineered T cell hybridomas to express additional CD3 molecules as well as CD4 with two amino acid substitutions that increase affinity to MHC class II molecules. The manipulated T cell hybridomas that were further transduced with retroviral vectors encoding TCRs of interest responded to cognate antigens more robustly than non-manipulated cells without evoking non-antigen specific reactivity. Of importance, the manipulation with CD3 and mutated human CD4 expression was effective in increasing responsiveness of T cell hybridomas to a wide variety of TCR, peptide, and MHC combinations across class II genetic loci (i.e. HLA-DR, HLA-DQ, HLA-DP, and murine H2-IA) and species (i.e. both humans and mice), and thus will be useful to identify antigen specificity of T cells.


Assuntos
Antígenos/farmacologia , Linhagem Celular Transformada/imunologia , Hibridomas/imunologia , Ativação Linfocitária/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T/imunologia , Antígenos/imunologia , Complexo CD3/imunologia , Linhagem Celular Transformada/citologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Hibridomas/citologia
11.
Diabetes ; 66(3): 722-734, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27920090

RESUMO

Type 1 diabetes results from chronic autoimmune destruction of insulin-producing ß-cells within pancreatic islets. Although insulin is a critical self-antigen in animal models of autoimmune diabetes, due to extremely limited access to pancreas samples, little is known about human antigenic targets for islet-infiltrating T cells. Here we show that proinsulin peptides are targeted by islet-infiltrating T cells from patients with type 1 diabetes. We identified hundreds of T cells from inflamed pancreatic islets of three young organ donors with type 1 diabetes with a short disease duration with high-risk HLA genes using a direct T-cell receptor (TCR) sequencing approach without long-term cell culture. Among 85 selected CD4 TCRs tested for reactivity to preproinsulin peptides presented by diabetes-susceptible HLA-DQ and HLA-DR molecules, one T cell recognized C-peptide amino acids 19-35, and two clones from separate donors responded to insulin B-chain amino acids 9-23 (B:9-23), which are known to be a critical self-antigen-driving disease progress in animal models of autoimmune diabetes. These B:9-23-specific T cells from islets responded to whole proinsulin and islets, whereas previously identified B:9-23 responsive clones from peripheral blood did not, highlighting the importance of proinsulin-specific T cells in the islet microenvironment.


Assuntos
Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Diabetes Mellitus Tipo 1/imunologia , Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Fragmentos de Peptídeos/imunologia , Proinsulina/imunologia , Precursores de Proteínas/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Adolescente , Peptídeo C/imunologia , Criança , Feminino , Antígenos HLA-DQ/imunologia , Antígenos HLA-DR/imunologia , Humanos , Células Secretoras de Insulina , Ilhotas Pancreáticas/citologia , Ilhotas Pancreáticas/patologia , Receptores de Antígenos de Linfócitos T/genética , Adulto Jovem
12.
Genetics ; 182(4): 1351-64, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19474202

RESUMO

Comparative genomics provides a powerful tool for the identification of genes that encode traits shared between crop plants and model organisms. Pathogen resistance conferred by plant R genes of the nucleotide-binding-leucine-rich-repeat (NB-LRR) class is one such trait with great agricultural importance that occupies a critical position in understanding fundamental processes of pathogen detection and coevolution. The proposed rapid rearrangement of R genes in genome evolution would make comparative approaches tenuous. Here, we test the hypothesis that orthology is predictive of R-gene genomic location in the Solanaceae using the pepper R gene Bs2. Homologs of Bs2 were compared in terms of sequence and gene and protein architecture. Comparative mapping demonstrated that Bs2 shared macrosynteny with R genes that best fit criteria determined to be its orthologs. Analysis of the genomic sequence encompassing solanaceous R genes revealed the magnitude of transposon insertions and local duplications that resulted in the expansion of the Bs2 intron to 27 kb and the frequently detected duplications of the 5'-end of R genes. However, these duplications did not impact protein expression or function in transient assays. Taken together, our results support a conservation of synteny for NB-LRR genes and further show that their distribution in the genome has been consistent with global rearrangements.


Assuntos
Genoma de Planta/genética , Imunidade Inata/genética , Proteínas de Plantas/genética , Solanaceae/genética , Sintenia/genética , Capsicum/genética , Rearranjo Gênico , Genes de Plantas , Genômica/métodos , Doenças das Plantas/imunologia , Solanum tuberosum/genética
13.
Plant Physiol ; 130(1): 234-43, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12226503

RESUMO

To further our understanding of how plants defend against the harmful effects of ultraviolet (UV) light, we characterized an Arabidopsis mutant hypersensitive to UV-B. This mutant, UV resistance locus 8-1 (uvr8-1), contains a single recessive mutation at the bottom of chromosome 5. Fine-scale mapping localized uvr8-1 to a 21-kb locus containing five predicted open reading frames. Sequencing of this entire region revealed that the uvr8-1 allele contains a 15-nucleotide deletion in a gene similar to the human guanine nucleotide exchange factor regulator of chromatin condensation 1. This mutation reduces the UV-B-mediated induction of flavonoids and blocks chalcone synthase mRNA and protein induction. In contrast, uvr8-1 has enhanced induction of PR1 and PR5 proteins in response to UV-B, an indication of increased UV-B injury. These results suggest that UVR8 acts in a UV-B signal transduction pathway leading to induction of flavonoid biosynthesis.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Proteínas de Ciclo Celular , Fatores de Troca do Nucleotídeo Guanina/genética , Proteínas Nucleares , Transdução de Sinais/fisiologia , Aciltransferases/metabolismo , Adaptação Fisiológica/fisiologia , Alelos , Arabidopsis/genética , Arabidopsis/efeitos da radiação , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/efeitos da radiação , Mapeamento Cromossômico , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Teste de Complementação Genética , Humanos , Dados de Sequência Molecular , Mutação , Fenilpropionatos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Deleção de Sequência , Raios Ultravioleta
14.
J Exp Bot ; 54(388): 1655-64, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12810854

RESUMO

The biosynthesis of capsaicinoids in the placenta of chilli fruit is modelled to require components of the fatty acid synthase (FAS) complex. Three candidate genes for subunits in this complex, Kas, Acl, and Fat, isolated based on differential expression, were characterized. Transcription of these three genes was placental-specific and RNA abundance was positively correlated with degree of pungency. Kas and Acl were mapped to linkage group 1 and Fat to linkage group 6. None of the genes is linked to the pungency locus, C, on linkage group 2. KAS accumulation was positively correlated with pungency. Western blots of placental extracts and histological sections both demonstrated that the accumulation of this enzyme was correlated with fruit pungency and KAS was immunolocalized to the expected cell layer, the placental epidermis. Enzyme activity of the recombinant form of the placental-specific KAS was confirmed using crude cell extracts. These FAS components are fruit-specific members of their respective gene families. These genes are predicted to be associated with Capsicum fruit traits, for example, capsaicinoid biosynthesis or fatty acid biosynthesis necessary for placental development.


Assuntos
3-Oxoacil-(Proteína de Transporte de Acila) Sintase/genética , Proteína de Transporte de Acila/genética , Capsicum/genética , Ácido Graxo Sintases/genética , Frutas/genética , Tioléster Hidrolases/genética , 3-Oxoacil-(Proteína de Transporte de Acila) Sintase/metabolismo , Proteína de Transporte de Acila/metabolismo , Sequência de Aminoácidos , Capsaicina/metabolismo , Capsicum/química , Capsicum/metabolismo , Mapeamento Cromossômico , Escherichia coli/genética , Escherichia coli/metabolismo , Ácido Graxo Sintases/metabolismo , Frutas/metabolismo , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Imuno-Histoquímica , Dados de Sequência Molecular , Sementes/genética , Sementes/metabolismo , Homologia de Sequência de Aminoácidos , Tioléster Hidrolases/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA