RESUMEN
PHYTOCHROME KINASE SUBSTRATE (PKS) proteins are involved in light-modulated changes in growth orientation. They act downstream of phytochromes to control hypocotyl gravitropism in the light and act early in phototropin signaling. Despite their importance for plant development, little is known about their molecular mode of action, except that they belong to a protein complex comprising phototropins at the plasma membrane (PM). Identifying evolutionary conservation is one approach to revealing biologically important protein motifs. Here, we show that PKS sequences are restricted to seed plants and that these proteins share 6 motifs (A to F from the N to the C terminus). Motifs A and D are also present in BIG GRAIN, while the remaining 4 are specific to PKSs. We provide evidence that motif C is S-acylated on highly conserved cysteines, which mediates the association of PKS proteins with the PM. Motif C is also required for PKS4-mediated phototropism and light-regulated hypocotyl gravitropism. Finally, our data suggest that the mode of PKS4 association with the PM is important for its biological activity. Our work, therefore, identifies conserved cysteines contributing to PM association of PKS proteins and strongly suggests that this is their site of action to modulate environmentally regulated organ positioning.
Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Fitocromo , Fitocromo/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteína S/metabolismo , Luz , Fototropismo , Hipocótilo , AcilaciónRESUMEN
High myopia is the most severe and pathological form of myopia. It occurs when the spherical refractive error exceeds -6.00 spherical diopters (SDs) or the axial length (AL) of the eye is greater than 26 mm. This article focuses on early-onset high myopia, an increasingly common condition that affects children under 10 years of age and can lead to other serious ocular pathologies. Through the genetic analysis of 21 families with early-onset high myopia, this study seeks to contribute to a better understanding of the role of genetics in this disease and to propose candidate genes. Whole-exome sequencing studies with a panel of genes known to be involved in the pathology were performed in families with inconclusive results: 3% of the variants found were classified as pathogenic, 6% were likely pathogenic and the remaining 91% were variants of uncertain significance. Most of the families in this study were found to have alterations in several of the proposed genes. This suggests a polygenic inheritance of the pathology due to the cumulative effect of the alterations. Further studies are needed to validate and confirm the role of these alterations in the development of early-onset high myopia and its polygenic inheritance.
Asunto(s)
Miopía , Niño , Humanos , Secuenciación del Exoma , Miopía/genéticaRESUMEN
Early-onset high myopia (EoHM) is a disease that causes a spherical refraction error of ≥-6 diopters before 10 years of age, with potential multiple ocular complications. In this article, we report a clinical and genetic study of 43 families with EoHM recruited in our center. A complete ophthalmological evaluation was performed, and a sample of peripheral blood was obtained from proband and family members. DNA was analyzed using a customized next-generation sequencing panel that included 419 genes related to ophthalmological disorders with a suspected genetic cause, and genes related to EoHM pathogenesis. We detected pathogenic and likely pathogenic variants in 23.9% of the families and detected variants of unknown significance in 76.1%. Of these, 5.7% were found in genes related to non-syndromic EoHM, 48.6% in genes associated with inherited retinal dystrophies that can include a syndromic phenotype, and 45.7% in genes that are not directly related to EoHM or retinal dystrophy. We found no candidate genes in 23% of the patients, which suggests that further studies are needed. We propose a systematic genetic analysis for patients with EoHM because it helps with follow-up, prognosis and genetic counseling.
Asunto(s)
Miopía , Distrofias Retinianas , Análisis Mutacional de ADN , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Mutación , Miopía/diagnóstico , Miopía/genética , Linaje , Distrofias Retinianas/genéticaRESUMEN
Hamelia patens (Rubiaceae), known as firebush, is a source of bioactive monoterpenoid oxindole alkaloids (MOAs) derived from monoterpenoid indole alkaloids (MIAs). With the aim of understanding the regulation of the biosynthesis of these specialized metabolites, micropropagated plants were elicited with jasmonic acid (JA) and salicylic acid (SA). The MOA production and MIA biosynthetic-related gene expression were evaluated over time. The production of MOAs was increased compared to the control up to 2-fold (41.3 mg g DW-1) at 72 h in JA-elicited plants and 2.5-fold (42.4 mg g DW-1) at 120 h in plants elicited with SA. The increment concurs with the increase in the expression levels of the genes HpaLAMT, HpaTDC, HpaSTR, HpaNPF2.9, HpaTHAS1, and HpaTHAS2. Interestingly, it was found that HpaSGD was downregulated in both treatments after 24 h but in the SA treatment at 120 h only was upregulated to 8-fold compared to the control. In this work, we present the results of MOA production in H. patens and discuss how JA and SA might be regulating the central biosynthetic steps that involve HpaSGD and HpaTHAS genes.
RESUMEN
PURPOSE: To report a case of fibrinous acute anterior uveitis associated with topical interferon-α2b (IFN-α2b) treatment for ocular surface squamous neoplasia in a patient with HLA-B27 uveitis predisposition. METHODS: Case report. RESULTS: We present the case of a 57-year-old man who received topical IFN-α2b as adjuvant therapy for a previously surgically removed ocular surface squamous neoplasia with affected surgical margins. Two weeks after topical IFN-α2b initiation, the patient was diagnosed with fibrinous acute anterior uveitis. Complementary tests to rule out other causes of uveitis resulted to be negative, except for HLA-B27, which tested positive. Response to treatment with topical corticosteroids and cyclopentolate was favorable. As IFN-α2b is considered an immune enhancer and has been widely associated with autoimmune side effects, topical therapy with IFN-α2b was temporally ceased until intraocular inflammation resolved. Topical IFN-α2b was resumed, and during follow-up, no signs of uveitis were detected. The main hypothesis is that IFN-α2b acts as a trigger for intraocular inflammation in individuals with uveitis predisposition. CONCLUSIONS: Topical IFN-α2b could trigger intraocular inflammation in patients with uveitis susceptibility. It may be reasonable to use IFN-α2b cautiously in patients with a known history of uveitis or uveitis predisposition.
Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de la Conjuntiva , Uveítis Anterior , Masculino , Humanos , Persona de Mediana Edad , Antígeno HLA-B27/uso terapéutico , Interferón-alfa/efectos adversos , Neoplasias de la Conjuntiva/tratamiento farmacológico , Uveítis Anterior/inducido químicamente , Uveítis Anterior/diagnóstico , Uveítis Anterior/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológicoAsunto(s)
Tos Ferina/epidemiología , Femenino , Humanos , Lactante , Masculino , España/epidemiología , Tos Ferina/diagnósticoRESUMEN
OBJECTIVES: To evaluate whether using D-dimer test results adjusted for age according to the formula proposed by Douma et al. improves diagnostic accuracy; to assess the appropriateness of ordering D-dimer tests on clinical suspicion of pulmonary embolism; and to explore the association of test results with the extension and severity of the embolism. MATERIAL AND METHODS: Retrospective observational study of 1833 cases in which D-dimer testing was ordered for patients in our hospital's emergency department in the course of a year. We calculated sensitivity, specificity, and positive and negative predictive values using our hospital's D-dimer cutoff of 250 µg/mL adjusted for age with a modification of Douma et al.'s formula. When information about pulmonary embolism extension and severity was on record, we assessed the correlation with test results. RESULTS: Adjusting D-dimer level for age increased the number of true negatives and the specificity and positive predictive value of the test. D-dimer level correlated significantly with the extension of pulmonary embolism (r=0.41, P<.05) but not with clinical severity. CONCLUSION: Adjusting the D-dimer test result by age improves accuracy in the diagnosis of pulmonary embolism, even though clinical suspicion in Spain does not follow guideline recommendations. Our findings suggest that Ddimer level correlates with the extension but not the severity of pulmonary embolism.
OBJETIVO: Valorar la mejora de la precisión diagnóstica del dímero D (DD) al ajustar por la edad aplicando la fórmula publicada por Douma et al., así como evaluar la adecuación de la solicitud del DD a la sospecha clínica y relacionar sus valores con la extensión y gravedad de la embolia pulmonar. METODO: Estudio observacional, retrospectivo que incluye 1.833 pacientes atendidos en el servicio de urgencias de nuestro hospital a lo largo de 1 año, a los que se solicitó determinación del DD. Se calculó sensibilidad, especificidad, valor predictivo positivo y negativo de su valor utilizando el punto de corte de nuestro centro (250 µg/mL) y ajustado por edad (fórmula de Douma et al. modificada) y se correlacionó con la extensión y gravedad de la embolia pulmonar cuando la hubo. RESULTADOS: El ajuste por edad del valor de DD supone aumentar la proporción de casos verdaderos negativos, la especificidad y el valor predictivo positivo de esta determinación. Se encuentra una correlación significativa entre el valor del DD con la extensión de la embolia pulmonar (r = 0,41, p < 0,05) pero no con la gravedad clínica del episodio. CONCLUSIONES: El ajuste del DD por la edad mejora la precisión diagnóstica de la embolia pulmonar, aunque, en nuestro entorno, su sospecha no se establece siguiendo las guías recomendadas. El valor del DD se relaciona con la extensión pero no con la gravedad de la embolia pulmonar.
Asunto(s)
Sangrado por Deficiencia de Vitamina K , Parto Domiciliario , Humanos , Recién Nacido , PadresRESUMEN
Down-regulation of CD4+CD25+ regulatory T (Treg) cell function might be beneficial to enhance the immunogenicity of viral and tumor vaccines or to induce breakdown of immunotolerance. Although the mechanism of suppression used by Treg cells remains controversial, it has been postulated that TGF-beta1 mediates their immunosuppressive activity. In this study, we show that P17, a short synthetic peptide that inhibits TGF-beta1 and TGF-beta2 developed in our laboratory, is able to inhibit Treg activity in vitro and in vivo. In vitro studies demonstrate that P17 inhibits murine and human Treg-induced unresponsiveness of effector T cells to anti-CD3 stimulation, in an MLR or to a specific Ag. Moreover, administration of P17 to mice immunized with peptide vaccines containing tumor or viral Ags enhanced anti-vaccine immune responses and improved protective immunogenicity against tumor growth or viral infection or replication. When CD4+ T cells purified from OT-II transgenic mice were transferred into C57BL/6 mice bearing s.c. EG.7-OVA tumors, administration of P17 improved their proliferation, reduced the number of CD4+Foxp3+ T cells, and inhibited tumor growth. Also, P17 prevented development of immunotolerance induced by oral administration of OVA by genetically modified Lactococcus lactis in DO11.10 transgenic mice sensitized by s.c. injection of OVA. These findings demonstrate that peptide inhibitors of TGF-beta may be a valuable tool to enhance vaccination efficacy and to break tolerance against pathogens or tumor Ags.
Asunto(s)
Regulación hacia Abajo/inmunología , Activación de Linfocitos/inmunología , Péptidos/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Factor de Crecimiento Transformador beta1/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/inmunología , Animales , Vacunas contra el Cáncer/inmunología , Línea Celular , Proliferación Celular/efectos de los fármacos , Femenino , Factores de Transcripción Forkhead/inmunología , Humanos , Inmunosupresores/farmacología , Activación de Linfocitos/efectos de los fármacos , Ratones , Neoplasias/inmunología , Neoplasias/patología , Isoformas de Proteínas/inmunología , Linfocitos T Reguladores/citología , Factor de Crecimiento Transformador beta2/antagonistas & inhibidores , Factor de Crecimiento Transformador beta2/inmunologíaRESUMEN
Pathologies such as liver fibrosis and scleroderma are characterized by harmful levels of transforming growth factor beta 1 (TGFbeta1). These levels could be neutralized if inhibitors of this cytokine were available. With this aim we searched for peptides with binding affinity for TGFbeta1 using a phage-displayed random 15-mer peptide library. Some peptides thus identified blocked activity of TGFbeta1 in vitro, as measured by their capacity to restore growth of Mv-1-Lu cells in presence of added TGFbeta1. Also, they inhibited TGFbeta1-dependent expression of collagen type I mRNA in liver of mice orally insulted with CCl(4). Intraperitoneal administration of 50 microg of peptide P17 (the most active 15-mer peptide, also referred to as P17(1-15)) inhibited expression of collagen type I mRNA by almost 100%. Interestingly, titration experiments showed that P17(1-12) (a peptide encompassing the first 12 amino acids of P17) was approximately four times more active than P17. These results suggest that both peptides, as well as others reported here, may be of therapeutic interest in processes requiring control of undesired high levels of TGFbeta1.