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1.
Vet Sci ; 11(6)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38922029

RESUMEN

The objective of the present case series was to investigate the various computed tomography findings of six dogs diagnosed with extraskeletal osteosarcoma (exOSA) at several locations. Among the tumors evaluated, four were subcutaneous, one was mammary, and one involved the intestinal tract. Intralesional mineralization was observed in all six dogs. Most of the tumors were moderately calcified, exhibited amorphous mineralization, and were heterogeneous on post-contrast imaging. Three of the tumors were peripherally enhanced, and regional lymphadenopathy was identified in two of the dogs, which was presumed to be metastatic. No lymph node calcification was reported. Although the presence of intralesional mineralization is not a pathognomonic finding, it was consistently identified in the present case series. Therefore, exOSA should be considered in the differential diagnosis when mineralization occurs in a mass unrelated to osseous structures.

2.
ACS Nano ; 18(25): 16126-16140, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38764224

RESUMEN

Traditional monoclonal antibodies such as Trastuzumab encounter limitations when treating Human Epidermal Growth Factor Receptor 2 (HER2)-positive breast cancer, particularly in cases that develop resistance. This study introduces plant-derived anti-HER2 variable fragments of camelid heavy chain domain (VHH) fragment crystallizable region (Fc) KEDL(K) antibody as a potent alternative for overcoming these limitations. A variety of biophysical techniques, in vitro assays, and in vivo experiments uncover the antibody's nanoscale binding dynamics with transmembrane HER2 on living cells. Single-molecule force spectroscopy reveals the rapid formation of two robust bonds, exhibiting approximately 50 pN force resistance and bond lifetimes in the second range. The antibody demonstrates a specific affinity for HER2-positive breast cancer cells, including those that are Trastuzumab-resistant. Moreover, in immune-deficient mice, the plant-derived anti-HER2 VHH-FcK antibody exhibits superior antitumor activity, especially against tumors that are resistant to Trastuzumab. These findings underscore the plant-derived antibody's potential as an impactful immunotherapeutic strategy for treating Trastuzumab-resistant HER2-positive breast cancer.


Asunto(s)
Neoplasias de la Mama , Resistencia a Antineoplásicos , Receptor ErbB-2 , Trastuzumab , Trastuzumab/química , Trastuzumab/farmacología , Humanos , Receptor ErbB-2/inmunología , Receptor ErbB-2/metabolismo , Receptor ErbB-2/antagonistas & inhibidores , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/inmunología , Animales , Femenino , Resistencia a Antineoplásicos/efectos de los fármacos , Ratones , Línea Celular Tumoral , Antineoplásicos Inmunológicos/farmacología , Antineoplásicos Inmunológicos/química , Proliferación Celular/efectos de los fármacos
3.
Am J Vet Res ; 85(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38457913

RESUMEN

OBJECTIVE: This study evaluated the effects of scanning position and contrast medium injection rate on pulmonary CT perfusion (CTP) images in healthy dogs. ANIMALS: 7 healthy Beagles. METHODS: Experiments involved 4 conditions: dorsal and sternal recumbency at 2.5 mL/s (first) and sternal recumbency with additional rates of 1.5 and 3.5 mL/s (second). Various parameters, including the initial time of venous enhancement (Tv), peak time of arterial enhancement (PTa), and peak enhancement values of the artery, were measured. The PTa to Tv interval was calculated. Perfusion mapping parameters (pulmonary blood flow, pulmonary blood volume, mean transit time, time to maximum, and time to peak) were determined in different lung regions (left and right dorsal, middle, and ventral). RESULTS: There are significant variations in most perfusion mapping parameters based on the pulmonary parenchymal location. Dorsal recumbency had a lower peak value of arterial enhancement than sternal recumbency. Pulmonary blood flow in the dorsal region and mean transit time and time to maximum in all regions showed no significant differences based on position. Pulmonary blood volume and time to peak varied with scanning position. The PTa to Tv interval did not differ based on the injection rate, but the injection time at 1.5 mL/s was longer than at other rates. All perfusion mapping parameters of the ventral region increased with higher injection rates. CLINICAL RELEVANCE: The recommended CTP imaging approach in dogs is a low injection rate of 1.5 mL/s in the sternal recumbency. This study provides reference ranges for perfusion parameters based on the pulmonary parenchymal location, contributing to the acquisition and application of pulmonary CTP images for differential diagnosis in small-breed dogs.


Asunto(s)
Medios de Contraste , Pulmón , Tomografía Computarizada por Rayos X , Animales , Perros , Tomografía Computarizada por Rayos X/veterinaria , Pulmón/diagnóstico por imagen , Pulmón/irrigación sanguínea , Medios de Contraste/administración & dosificación , Masculino , Femenino , Circulación Pulmonar/fisiología
4.
Cell Mol Life Sci ; 79(2): 87, 2022 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-35067747

RESUMEN

Aminoacyl-tRNA synthetases (ARSs) are emerging as important regulators in various immune diseases; however, their roles in immune cells remain unclear. In this study, using alanyl-tRNA synthetase (AARS) mutant (sti) mice with neurodegenerative disorder, we investigated the effect of translational fidelity in immune cells. Dysfunctional AARS caused disorders in immune cell responses and cellularity. The impairment was caused by dampened TCR signaling than cytokine signaling. Therefore, sti mutant inhibits TCR signaling, impeding T cell survival and responses. B cell numbers were decreased in sti mice. Despite low B cell cellularity, serum IgM, IgA, and IgE levels were higher in sti mice than in wild-type mice. Misacylation of ARS and the consequent translational infidelity induce disturbances in signaling pathways critical for immune cell survival and responses. Our findings provide a novel mechanism by which translational fidelity might play a critical role in cellular and humoral immune responses.


Asunto(s)
Aminoacil-ARNt Sintetasas/genética , Linfocitos B/inmunología , Linfocitos T/inmunología , Aminoacil-ARNt Sintetasas/metabolismo , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Proliferación Celular/efectos de los fármacos , Citocinas/farmacología , Femenino , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Inmunoglobulina A/sangre , Inmunoglobulina E/sangre , Inmunoglobulina M/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutagénesis , Receptores de Antígenos de Linfocitos T/metabolismo , Transducción de Señal/efectos de los fármacos , Linfocitos T/citología , Linfocitos T/metabolismo
5.
Genes (Basel) ; 12(5)2021 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-33923067

RESUMEN

In plants, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a main enzyme in the glycolytic pathway. It plays an essential role in glycerolipid metabolism and response to various stresses. To examine the function of PsGAPDH (Pleurotus sajor-caju GAPDH) in response to abiotic stress, we generated transgenic rice plants with single-copy/intergenic/homozygous overexpression PsGAPDH (PsGAPDH-OX) and investigated their responses to salinity stress. Seedling growth and germination rates of PsGAPDH-OX were significantly increased under salt stress conditions compared to those of the wild type. To elucidate the role of PsGAPDH-OX in salt stress tolerance of rice, an Illumina HiSeq 2000 platform was used to analyze transcriptome profiles of leaves under salt stress. Analysis results of sequencing data showed that 1124 transcripts were differentially expressed. Using the list of differentially expressed genes (DEGs), functional enrichment analyses of DEGs such as Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed. KEGG pathway enrichment analysis revealed that unigenes exhibiting differential expression were involved in starch and sucrose metabolism. Interestingly, trehalose-6-phosphate synthase (TPS) genes, of which expression was enhanced by abiotic stress, showed a significant difference in PsGAPDH-OX. Findings of this study suggest that PsGAPDH plays a role in the adaptation of rice plants to salt stress.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/genética , Oryza/genética , Proteínas de Plantas/genética , Estrés Salino , Transcriptoma , Regulación de la Expresión Génica de las Plantas , Gliceraldehído-3-Fosfato Deshidrogenasa (Fosforilante)/metabolismo , Oryza/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Proteínas de Plantas/metabolismo , Regulación hacia Arriba
6.
Toxins (Basel) ; 12(12)2020 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-33353166

RESUMEN

Dinoflagellates are an important group of phytoplanktons, characterized by two dissimilar flagella and distinctive features of both plants and animals. Dinoflagellate-generated harmful algal blooms (HABs) and associated damage frequently occur in coastal areas, which are concomitant with increasing eutrophication and climate change derived from anthropogenic waste and atmospheric carbon dioxide, respectively. The severe damage and harmful effects of dinoflagellate phycotoxins in the fishing industry have been recognized over the past few decades, and the management and monitoring of HABs have attracted much attention, leaving aside the industrial application of their valuable toxins. Specific modes of action of the organisms' toxins can effectively be utilized for producing beneficial materials, such as Botox and other therapeutic agents. This review aims to explore the potential industrial applications of marine dinoflagellate phycotoxins; furthermore, this review focuses on their modes of action and summarizes the available knowledge on them.


Asunto(s)
Cambio Climático , Dinoflagelados/aislamiento & purificación , Monitoreo del Ambiente/métodos , Explotaciones Pesqueras , Floraciones de Algas Nocivas , Animales , Monitoreo del Ambiente/normas , Explotaciones Pesqueras/normas , Humanos
7.
Biomolecules ; 10(2)2020 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-32092955

RESUMEN

Lectins have the ability to bind specific carbohydrates and they have potential applications as medical and pharmacological agents. The unique structure and usefulness of red algal lectin have been reported, but these lectins are limited to a few marine algal groups. In this study, a novel mannose-binding lectin from Grateloupia chiangii (G. chiangii lectin, GCL) was purified using antiviral screens and affinity chromatography. We characterized the molecular weight, agglutination activity, hemagglutination activity, and heat stability of GCL. To determine the carbohydrate specificity, a glycan microarray was performed. GCL showed strong binding affinity for Maltohexaose-ß-Sp1 and Maltoheptaose-ß-Sp1 with weak affinity for other monosaccharides and preferred binding to high-mannan structures. The N-terminal sequence and peptide sequence of GCL were determined using an Edman degradation method and LC-MS/MS, and the cDNA and peptide sequences were deduced. GCL was shown to consist of 231 amino acids (24.9 kDa) and the N-terminus methionine was eliminated after translation. GCL possessed a tandem repeat structure of six domains, similar to the other red algal lectins. The mannose binding properties and tandem repeat structure of GCL may confer it the potential to act as an antiviral agent for protection against viral infection.


Asunto(s)
Proteínas Algáceas/química , Antivirales/química , Lectina de Unión a Manosa/química , Rhodophyta/química , Proteínas Algáceas/metabolismo , Proteínas Algáceas/farmacología , Animales , Antivirales/metabolismo , Antivirales/farmacología , Perros , Pruebas de Hemaglutinación , Caballos , Células de Riñón Canino Madin Darby , Lectina de Unión a Manosa/metabolismo , Lectina de Unión a Manosa/farmacología , Unión Proteica , Rhodophyta/metabolismo , Ovinos , Virosis/tratamiento farmacológico , Virus/efectos de los fármacos
8.
J Mol Microbiol Biotechnol ; 28(4): 169-178, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30566956

RESUMEN

The algal cell wall is a potent barrier for delivery of transgenes for genetic engineering. Conventional methods developed for higher plant systems are often unable to penetrate or remove algal cell walls owing to their unique physical and chemical properties. Therefore, we developed a simple transformation method for Chlamydomonas reinhardtii using commercially available enzymes. Out of 7 enzymes screened for cell wall disruption, a commercial form of subtilisin (Alcalase) was the most effective at a low concentration (0.3 Anson units/mL). The efficiency was comparable to that of gamete lytic enzyme, a protease commonly used for the genetic transformation of C. reinhardtii. The transformation efficiency of our noninvasive method was similar to that of previous methods using autolysin as a cell wall-degrading enzyme in conjunction with glass bead transformation. Subtilisin showed approximately 35% sequence identity with sporangin, a hatching enzyme of C. reinhardtii, and shared conserved active domains, which may explain the effective cell wall degradation. Our trans-formation method using commercial subtilisin is more reliable and time saving than the conventional method using autolysin released from gametes for cell wall lysis.


Asunto(s)
Pared Celular/metabolismo , Chlamydomonas reinhardtii/citología , Subtilisina/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/ultraestructura , Chlamydomonas reinhardtii/genética , Vidrio , Metaloendopeptidasas/metabolismo , Alineación de Secuencia , Especificidad por Sustrato , Subtilisina/farmacología , Transformación Genética
9.
Biomolecules ; 8(4)2018 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-30441842

RESUMEN

Lectin is an important protein in medical and pharmacological applications. Impurities in lectin derived from natural sources and the generation of inactive proteins by recombinant technology are major obstacles for the use of lectins. Expressing recombinant lectin with a tandem repeat structure can potentially overcome these problems, but few studies have systematically examined this possibility. This was investigated in the present study using three distinct forms of recombinant mannose-binding lectin from Bryopsis plumosa (BPL2)-i.e., the monomer (rD1BPL2), as well as the dimer (rD2BPL2), and tetramer (rD4BPL2) arranged as tandem repeats. The concentration of the inducer molecule isopropyl ß-D-1-thiogalactopyranoside and the induction time had no effect on the efficiency of the expression of each construct. Of the tested constructs, only rD4BPL2 showed hemagglutination activity towards horse erythrocytes; the activity of towards the former was 64 times higher than that of native BPL2. Recombinant and native BPL2 showed differences in carbohydrate specificity; the activity of rD4BPL2 was inhibited by the glycoprotein fetuin, whereas that of native BPL2 was also inhibited by d-mannose. Our results indicate that expression as tandem repeat sequences can increase the efficiency of lectin production on a large scale using a bacterial expression system.


Asunto(s)
Chlorophyta/química , Lectina de Unión a Manosa/química , Lectina de Unión a Manosa/metabolismo , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Secuencias Repetidas en Tándem , Secuencia de Aminoácidos , Animales , Carbohidratos/química , Pruebas de Hemaglutinación , Caballos , Lectina de Unión a Manosa/aislamiento & purificación , Lectinas de Plantas/aislamiento & purificación , Proteínas Recombinantes/aislamiento & purificación , Ovinos , Solubilidad
10.
Int J Cancer ; 143(5): 1212-1223, 2018 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-29577276

RESUMEN

Previous studies have shown that soluble common γ-chain (sγc) modulates CD4+ T cell immunity with antagonistic functions in γc cytokine signaling. However, the role of sγc in functional properties of effector CD8+ T cells has not been fully defined. In this study, we report a new mechanism by which the anti-tumor activity of mouse CD8+ T cells is suppressed in sγc of their own producing. While sγc significantly inhibits cytotoxicity of CD8+ T cells, blocking sγc production by genetic modification leads to potentiated effector function of CD8+ T cells, establishing persistent CD8+ T cells. This is due to the modulation of IL-2 and IL-15 signaling, which is required for expansion and survival of CD8+ T cells as well as for optimal cytotoxic activity. More efficient management of tumor growth was achieved by an adoptive transfer of sγc-deficient CD8+ T cells than that of wild-type or sγc-overexpressing CD8+ T cells. Blocking of IL-2 and IL-15 signaling by sγc attenuates the capacity of CD8+ T cells to mount an optimal response to the tumor, with both quantitative and qualitative effects on antigen-specific CD8+ T cells. These results could have a critical implication for the generation and survival of optimal effector T cells for adoptive immunotherapy of cancer.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Inmunoterapia , Subunidad gamma Común de Receptores de Interleucina/fisiología , Interleucina-15/inmunología , Interleucina-2/inmunología , Neoplasias/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Humanos , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Transducción de Señal , Células Tumorales Cultivadas
11.
Mar Drugs ; 16(1)2018 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-29303968

RESUMEN

Lectins, characterized by their carbohydrate-binding ability, have extensive practical applications. However, their industrial use is limited due to impurity. Thus, quality-controlled production of recombinant lectin is necessary. In this study, the algal lectin BPL3 (Bryopsis plumosa lectin 3) was successfully produced using a bacterial expression system, BL21(DE3), with an artificial repeated structure (dimeric construct). Recombinant dimeric BPL3 (rD2BPL3) was confirmed by LC-MS/MS spectrometry. Expression efficiency was greater for the construct with the repeat structure (rD2BPL3) than the monomeric form (rD1BPL3). Optimal conditions for expression were 1 mM IPTG at 20 °C. Recombinant lectin was purified under denaturing conditions and refolded by the flash dilution method. Recombinant BPL3 was solubilized in 1× PBS containing 2 M urea. rD2BPL3 showed strong hemagglutination activity using human erythrocyte. rD2BPL3 had a similar sugar specificity to that of the native protein, i.e., to N-acetyl-glucosamine (GlcNAc) and N-acetyl-galactosamine (GalNAc). Glycan array results showed that recombinant BPL3 and native BPL3 exhibited different binding properties. Both showed weak binding activity to α-Man-Sp. Native BPL3 showed strong binding specificity to the alpha conformation of amino sugars, and rD2BPL3 had binding activity to the beta conformation. The process developed in this study was suitable for the quality-controlled large-scale production of recombinant lectins.


Asunto(s)
Acetilgalactosamina/metabolismo , Acetilglucosamina/metabolismo , Proteínas Algáceas/metabolismo , Lectinas/metabolismo , Proteínas Algáceas/química , Proteínas Algáceas/aislamiento & purificación , Cromatografía Liquida , Eritrocitos/metabolismo , Pruebas de Hemaglutinación , Humanos , Lectinas/química , Lectinas/aislamiento & purificación , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Espectrometría de Masas en Tándem
12.
Mitochondrial DNA B Resour ; 3(2): 935-936, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-33474370

RESUMEN

In the present report, we describe the first sequencing and assembly of the complete mitochondrial genome of Cheilio inermis. The mitochondrial genome of C. inermis, with 16,494 bp in length, has the typical vertebrate mitochondrial gene arrangement. It contains 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and a control region. All the tRNA genes typically formed a cloverleaf secondary structure. Phylogenetic analysis using mitochondrial genomes of 11 species showed that C. inermis formed monophyletic group with other Labridae species.

13.
Artículo en Inglés | MEDLINE | ID: mdl-28331303

RESUMEN

Cigarette smoking (CS) is a major cause of considerable morbidity and mortality by inducing lung cancer and COPD. COPD, a smoking-related disorder, is closely related to the alteration of immune system and inflammatory processes that are specifically mediated by T cells. Soluble common gamma chain (sγc) has recently been identified as a critical regulator of the development and differentiation of T cells. We examined the effects of sγc in a cigarette smoke extract (CSE) mouse model. The sγc level in CSE mice serum is significantly downregulated, and the cellularity of lymph node (LN) is systemically reduced in the CSE group. Overexpression of sγc enhances the cellularity and IFNγ production of CD8 T cells in LN and also enhances Th1 and Th17 differentiation of CD4 T cells in the respiratory tract. Mechanistically, the downregulation of sγc expression mediated by CSE is required to prevent excessive inflammatory T cell responses. Therefore, our data suggest that sγc may be one of the target molecules for the control of immunopathogenic progresses in COPD.


Asunto(s)
Subunidad gamma Común de Receptores de Interleucina/inmunología , Pulmón/inmunología , Neumonía/inmunología , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Subgrupos de Linfocitos T/inmunología , Animales , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Interferón gamma/inmunología , Interferón gamma/metabolismo , Subunidad gamma Común de Receptores de Interleucina/genética , Subunidad gamma Común de Receptores de Interleucina/metabolismo , Pulmón/patología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Ratones Endogámicos C57BL , Ratones Transgénicos , Neumonía/etiología , Neumonía/genética , Neumonía/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/etiología , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Transducción de Señal , Humo/efectos adversos , Fumar/efectos adversos , Subgrupos de Linfocitos T/metabolismo , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Factores de Tiempo
14.
Mediators Inflamm ; 2017: 9096829, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28127156

RESUMEN

IL-7 signaling via IL-7Rα and common γ-chain (γc) is necessary for the development and homeostasis of T cells. Although the delicate mechanism in which IL-7Rα downregulation allows the homeostasis of T cell with limited IL-7 has been well known, the exact mechanism behind the interaction between IL-7Rα and γc in the absence or presence of IL-7 remains unclear. Additionally, we are still uncertain as to how only IL-7Rα is separately downregulated by the binding of IL-7 from the IL-7Rα/γc complex. We demonstrate here that 4G3, TUGm2, and 3E12 epitope masking of γc protein are induced in the presence of IL-7, indicating that the epitope alteration is induced by IL-7 binding to the preassembled receptor core. Moreover, the epitope masking of γc protein is inversely correlated with the expression of IL-7Rα upon IL-7 binding, implying that the structural alteration of γc might be involved in the regulation of IL-7Rα expression. The conformational change in γc upon IL-7 binding may contribute not only to forming the functional IL-7 signaling complex but also to optimally regulating the expression of IL-7Rα.


Asunto(s)
Epítopos/química , Subunidad gamma Común de Receptores de Interleucina/química , Interleucina-7/metabolismo , Receptores de Interleucina-7/química , Animales , Anticuerpos Monoclonales/química , Citocinas/metabolismo , Humanos , Cinética , Ratones , Ratones Endogámicos C57BL , Fosforilación , Unión Proteica , Dominios Proteicos , Transducción de Señal
15.
Mitochondrial DNA B Resour ; 2(2): 785-786, 2017 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33473979

RESUMEN

Parupeneus barberinus is a tropical/subtropical reef-dwelling marine fish belonging to the family Mullidae. Herein, we report the first sequencing and assembly of the complete mitochondrial genome of P. barberinus. The complete mitochondrial genome is 16,560 bp long and has the typical vertebrate mitochondrial gene arrangement, consisting of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and a control region. Phylogenetic analysis using mitochondrial genomes of 18 species showed that P. barberinus is clustered with P. multifasciatus and P. chrysopleuron and rooted with other Mullidae species. This mitochondrial genome provides potentially important resources for addressing taxonomic issues and studying molecular evolution.

16.
Plant Physiol ; 169(1): 233-65, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26175514

RESUMEN

The legume-rhizobium symbiosis is initiated through the activation of the Nodulation (Nod) factor-signaling cascade, leading to a rapid reprogramming of host cell developmental pathways. In this work, we combine transcriptome sequencing with molecular genetics and network analysis to quantify and categorize the transcriptional changes occurring in roots of Medicago truncatula from minutes to days after inoculation with Sinorhizobium medicae. To identify the nature of the inductive and regulatory cues, we employed mutants with absent or decreased Nod factor sensitivities (i.e. Nodulation factor perception and Lysine motif domain-containing receptor-like kinase3, respectively) and an ethylene (ET)-insensitive, Nod factor-hypersensitive mutant (sickle). This unique data set encompasses nine time points, allowing observation of the symbiotic regulation of diverse biological processes with high temporal resolution. Among the many outputs of the study is the early Nod factor-induced, ET-regulated expression of ET signaling and biosynthesis genes. Coupled with the observation of massive transcriptional derepression in the ET-insensitive background, these results suggest that Nod factor signaling activates ET production to attenuate its own signal. Promoter:ß-glucuronidase fusions report ET biosynthesis both in root hairs responding to rhizobium as well as in meristematic tissue during nodule organogenesis and growth, indicating that ET signaling functions at multiple developmental stages during symbiosis. In addition, we identified thousands of novel candidate genes undergoing Nod factor-dependent, ET-regulated expression. We leveraged the power of this large data set to model Nod factor- and ET-regulated signaling networks using MERLIN, a regulatory network inference algorithm. These analyses predict key nodes regulating the biological process impacted by Nod factor perception. We have made these results available to the research community through a searchable online resource.


Asunto(s)
Etilenos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Medicago truncatula/genética , Medicago truncatula/microbiología , Proteínas de Plantas/metabolismo , Raíces de Plantas/genética , Transducción de Señal/efectos de los fármacos , Transcriptoma/genética , Vías Biosintéticas/efectos de los fármacos , Vías Biosintéticas/genética , Análisis por Conglomerados , Etilenos/farmacología , Retroalimentación Fisiológica , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Ontología de Genes , Redes Reguladoras de Genes , Genes de Plantas , Medicago truncatula/efectos de los fármacos , Proteínas de Plantas/genética , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/microbiología , Rhizobium/efectos de los fármacos , Rhizobium/fisiología , Transducción de Señal/genética , Simbiosis/genética , Factores de Tiempo , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Transcriptoma/efectos de los fármacos
17.
Mol Genet Genomics ; 287(10): 765-84, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22915303

RESUMEN

Completion of the sequencing of the Brassica rapa genome enabled us to undertake a genome-wide identification and functional study of the gene families related to the morphological diversity and agronomic traits of Brassica crops. In this study, we identified the auxin response factor (ARF) gene family, which is one of the key regulators of auxin-mediated plant growth and development in the B. rapa genome. A total of 31 ARF genes were identified in the genome. Phylogenetic and evolutionary analyses suggest that ARF genes fell into four major classes and were amplified in the B. rapa genome as a result of a recent whole genome triplication after speciation from Arabidopsis thaliana. Despite its recent hexaploid ancestry, B. rapa includes a relatively small number of ARF genes compared with the 23 members in A. thaliana, presumably due to a paralog reduction related to repetitive sequence insertion into promoter and non-coding transcribed region of the genes. Comparative genomic and mRNA sequencing analyses demonstrated that 27 of the 31 BrARF genes were transcriptionally active, and their expression was affected by either auxin treatment or floral development stage, although 4 genes were inactive, suggesting that the generation and pseudogenization of ARF members are likely to be an ongoing process. This study will provide a fundamental basis for the modification and evolution of the gene family after a polyploidy event, as well as a functional study of ARF genes in a polyploidy crop species.


Asunto(s)
Brassica rapa/genética , Evolución Molecular , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Filogenia , Proteínas de Plantas/genética , Factores de Transcripción/genética , Brassica rapa/metabolismo , Variación Genética , Ácidos Indolacéticos/metabolismo
18.
Biochem J ; 443(1): 49-56, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22214184

RESUMEN

TDP1 (tyrosyl-DNA phosphodiesterase 1), a member of the PLD (phospholipase D) superfamily, catalyses the hydrolysis of a phosphodiester bond between a tyrosine residue and the 3'-phosphate of DNA. We have previously identified and characterized the AtTDP gene in Arabidopsis thaliana, an orthologue of yeast and human TDP1 genes. Sequence alignment of TDP1 orthologues revealed that AtTDP has both a conserved C-terminal TDP domain and, uniquely, an N-terminal SMAD/FHA (forkhead-associated) domain. To help understand the function of this novel enzyme, we analysed the substrate saturation kinetics of full-length AtTDP compared with a truncated AtTDP mutant lacking the N-terminal FHA domain. The recombinant AtTDP protein hydrolysed a single-stranded DNA substrate with Km and kcat/Km values of 703±137 nM and (1.5±0.04)×10(9) M(-1)·min(-1) respectively. The AtTDP-(Δ1-122) protein (TDP domain) showed kinetic parameters that were equivalent to those of the full-length AtTDP protein. A basic amino acid sequence (RKKVKP) within the AtTDP-(Δ123-605) protein (FHA domain) was necessary for nuclear localization of AtTDP. Analysis of active-site mutations showed that a histidine and a lysine residue in each of the HKD motifs were critical for enzyme activity. Vanadates, inhibitors of phosphoryl transfer reactions, inhibited AtTDP enzymatic activity and retarded the growth of an Arabidopsis tdp mutant. Finally, we showed that expression of the AtTDP gene could complement a yeast tdp1Δrad1Δ mutant, rescuing the growth inhibitory effects of vanadate analogues and CPT (camptothecin). Taken together, the results of the present study demonstrate the structure-based function of AtTDP through which AtTDP can repair DNA strand breaks in plants.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Reparación del ADN , Hidrolasas Diéster Fosfóricas/metabolismo , Hojas de la Planta/enzimología , Transporte Activo de Núcleo Celular , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Camptotecina/farmacología , Dominio Catalítico , Clorofila/metabolismo , Cinética , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Señales de Localización Nuclear , Inhibidores de Fosfodiesterasa/farmacología , Hidrolasas Diéster Fosfóricas/química , Hidrolasas Diéster Fosfóricas/genética , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Vanadatos/farmacología
19.
Blood ; 118(9): 2609-17, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-21715313

RESUMEN

Any role for reduced-intensity conditioning (RIC) before hematopoietic cell transplantation (HCT) from a human leukocyte antigen (HLA)-haploidentical donor remains to be defined. We therefore assessed 83 patients (age, 16-70 years): 68 with acute leukemia (including 34 in remission and 34 with refractory disease) and 15 patients with myelodysplastic syndrome, in HCT trials using RIC with busulfan, fludarabine, and antithymocyte globulin. The HLA-haploidentical donors, offspring (n = 38), mothers (n = 24), or siblings (n = 21) of patients, underwent leukapheresis after receiving granulocyte colony-stimulating factor, and donated cells were transplanted without further manipulation. Cyclosporine and methotrexate were given for GVHD prophylaxis. The cumulative incidences of neutrophil engraftment, grade 2 to 4 acute GVHD, chronic GVHD, and transplantation-related mortality after HCT, were 92%, 20%, 34%, and 18%, respectively. After a median follow-up time of 26.6 months (range, 16.8-78.8 months), the event-free and overall survival rates were 56% and 45%, respectively, for patients with acute leukemia in remission; 9% and 9%, respectively, for patients with refractory acute leukemia; and 53% and 53%, respectively, for patients with myelodysplastic syndrome. HCT from an HLA-haploidentical family member resulted in favorable outcomes when RIC containing antithymocyte globulin was performed. This study is registered at www.clinicaltrials.gov as #NCT00521430 and #NCT00732316.


Asunto(s)
Suero Antilinfocítico/administración & dosificación , Busulfano/administración & dosificación , Antígenos HLA/análisis , Trasplante de Células Madre Hematopoyéticas/métodos , Leucemia/cirugía , Síndromes Mielodisplásicos/cirugía , Trasplante de Células Madre de Sangre Periférica/métodos , Acondicionamiento Pretrasplante/métodos , Vidarabina/análogos & derivados , Enfermedad Aguda , Adolescente , Adulto , Anciano , Supervivencia sin Enfermedad , Femenino , Supervivencia de Injerto , Enfermedad Injerto contra Huésped/prevención & control , Factor Estimulante de Colonias de Granulocitos/farmacología , Histocompatibilidad , Humanos , Infecciones , Estimación de Kaplan-Meier , Leucemia/mortalidad , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/mortalidad , Estudios Retrospectivos , Linfocitos T/inmunología , Donantes de Tejidos , Resultado del Tratamiento , Vidarabina/administración & dosificación , Adulto Joven
20.
J Exp Bot ; 62(13): 4571-81, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21624980

RESUMEN

In Arabidopsis, inflorescence stem formation is a critical process in phase transition from the vegetative to the reproductive state. Although inflorescence stem development has been reported to depend on the expression of a variety of genes during floral induction and repression, little is known about the molecular mechanisms involved in the control of inflorescence stem formation. By activation T-DNA tagging mutagenesis of Arabidopsis, a dominant gain-of-function mutation, eve1-D (eternally vegetative phase1-Dominant), which has lost the ability to form an inflorescence stem, was isolated. The eve1-D mutation exhibited a dome-shaped primary shoot apical meristem (SAM) in the early vegetative stage, similar to that seen in the wild-type SAM. However, the SAM in the eve1-D mutation failed to transition into an inflorescence meristem (IM) and eventually reached senescence without ever leaving the vegetative phase. The eve1-D mutation also displayed pleiotropic phenotypes, including lobed and wavy rosette leaves, short petioles, and an increased number of rosette leaves. Genetic analysis indicated that the genomic location of the EVE1 gene in Arabidopsis thaliana corresponded to a bacterial artificial chromosome (BAC) F4C21 from chromosome IV at ∼17cM which encoded a novel ubiquitin family protein (At4g03350), consisting of a single exon. The EVE1 protein is composed of 263 amino acids, contains a 52 amino acid ubiquitin domain, and has no glycine residue related to ubiquitin activity at the C-terminus. The eve1-D mutation provides a way to study the regulatory mechanisms that control phase transition from the vegetative to the reproductive state.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Inflorescencia/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/genética , Ubiquitina/metabolismo , Ubiquitinas/metabolismo , Secuencia de Aminoácidos , Arabidopsis/anatomía & histología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Regulación hacia Abajo/genética , Regulación del Desarrollo de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Genes de Plantas/genética , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Inflorescencia/genética , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Meristema/citología , Meristema/metabolismo , Meristema/ultraestructura , Datos de Secuencia Molecular , Mutación/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fenotipo , Hojas de la Planta/anatomía & histología , Hojas de la Planta/genética , Hojas de la Planta/ultraestructura , Tallos de la Planta/metabolismo , Plantas Modificadas Genéticamente , ARN sin Sentido/genética , ARN sin Sentido/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Ubiquitina/química , Ubiquitina/genética , Ubiquitinas/química , Ubiquitinas/genética
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