RESUMEN
The tripeptide reduced glutathione (GSH; γ-glutamate [Glu]-cysteine [Cys]-glycine) is a major endogenous antioxidant in both animal and plant cells. It also functions as a neurotransmitter mediating communication among neurons in the central nervous system of animals through modulating specific ionotropic Glu receptors (GLRs) in the membrane. Little is known about such signaling roles in plant cells. Here, we report that transient rises in cytosolic calcium triggered by exogenous GSH in Arabidopsis (Arabidopsis thaliana) leaves were sensitive to GLR antagonists and abolished in loss-of-function atglr3.3 mutants. Like the GSH biosynthesis-defective mutant PHYTOALEXIN DEFICIENT2, atglr3.3 showed enhanced susceptibility to the bacterial pathogen Pseudomonas syringae pv tomato DC3000. Pathogen-induced defense marker gene expression was also decreased in atglr3.3 mutants. Twenty-seven percent of genes that were rapidly responsive to GSH treatment of seedlings were defense genes, most of which were dependent on functional AtGLR3.3, while GSH suppressed pathogen propagation through the AtGLR3.3-dependent pathway. Eight previously identified putative AtGLR3.3 ligands, GSH, oxidized glutathione, alanine, asparagine, Cys, Glu, glycine, and serine, all elicited the AtGLR3.3-dependent cytosolic calcium transients, but only GSH and Cys induced the defense response, with the Glu-induced AtGLR3.3-dependent transcription response being much less apparent than that triggered by GSH. Together, these observations suggest that AtGLR3.3 is required for several signaling effects mediated by extracellular GSH, even though these effects may not be causally related.
Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/inmunología , Calcio/metabolismo , Citosol/metabolismo , Glutatión/metabolismo , Inmunidad Innata , Receptores de Glutamato/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/metabolismo , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/inmunología , Regulación de la Expresión Génica de las Plantas , Glutatión/farmacología , Inmunidad Innata/efectos de los fármacos , Ligandos , Mutación , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Plantas Modificadas Genéticamente , Pseudomonas syringae/patogenicidad , Receptores de Glutamato/genética , Receptores de Glutamato/inmunología , Plantones/genética , Plantones/inmunología , Plantones/microbiologíaRESUMEN
RATIONALE: Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) is a rare neurodevelopmental disorder caused by loss-of-function variants in the Nuclear Receptor Subfamily 2 Group F Member 1 (NR2F1). Here, we report a case of fetal BBSOAS. The fetus is typically featured by bilateral ventricle widening in the late second trimester, meanwhile, a 7.94-Mb deletion fragment on 5q14.3q15 involving the whole NR2F1 gene was confirmed by copy number variation sequencing (CNV-Seq) combined with karyotyping analysis. Our aim is to provide comprehensive prenatal clinical management strategy for fetal BBSOAS. PATIENT CONCERNS: A 29-year-old primipara and her husband were referred to our prenatal diagnosis center due to the widening of bilateral ventricles at 29 + 1 weeks of gestation age. DIAGNOSES: Ultrasound revealed the fetal widening posterior horns of bilateral ventricles at the GA of 27 + 3 weeks, 11 mm on the left and 10 mm on the right. At the following 29 + 1 weeks, ultrasound showed the posterior horn of the left lateral ventricle: 12 mm while the width of the right decreased to 9 mm, and intracranial arachnoid cyst. Furthermore, MRI confirmed that intracranial cyst might originate from an enlarged cisterna venae magnae cerebri, with mild dilation of 13.5 mm on the left ventricle. The fetal karyotyping analysis and CNV-Seq detection confirmed a 7.94-Mb deleted fragment on 5q14.3q15 (89340000_97280000) through the amniocentesis at 29 + 4 weeks of GA. INTERVENTIONS: The fetus was closely monitored and underwent the following assessment by the multidisciplinary team. OUTCOMES: The pregnancy was terminated in the end. LESSONS: It is vital to use molecular and cytogenetical detections combined with a dynamic development history to make a definite diagnosis and evaluate the genetic status for the fetuses with BBSOAS.
Asunto(s)
Discapacidad Intelectual , Atrofias Ópticas Hereditarias , Atrofia Óptica , Adulto , Factor de Transcripción COUP I/genética , Variaciones en el Número de Copia de ADN , Femenino , Feto , Ventrículos Cardíacos , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/genética , Atrofias Ópticas Hereditarias/genética , Atrofia Óptica/genética , Embarazo , Ultrasonografía PrenatalRESUMEN
Potato virus Y (PVY) is an important pathogen of potato (Solanum tuberosum). Although the PBS1-RPS5 immune system is well documented in Arabidopsis thaliana, it has not been reported in potato. In Arabidopsis, the bacterial effector AvrPphB cleaves AtPBS1 to trigger an immune response. Here, we show that the AvrPphB-triggered immune response is mediated by StPBS1, a close homologue of AtPBS1 in potato. However, downstream signalling of StPBS1 was mediated by unknown resistance (R) proteins other than potato orthologues of AtRPS5 and HvPBR1, which is important for HvPBS1 signalling in barley. Immune signalling of StPBS1 is mediated by the AvrPphB C-terminal cleavage domain and an STKPQ motif, in contrast to AtPBS1-mediated immunity in which both AvrPphB cleavage fragments and an SEMPH motif are essential. The cleavage sequence of AvrPphB in StPBS1 was replaced with that of the PVY NIa-Pro protease to obtain StPBS1NIa . StPBS1NIa overexpression potato displayed stronger immunity to PVY infection than did the StPBS1 transgenic lines. StPBS1NIa was cleaved at the expected target site by NIa-Pro protease from PVY. Thus, we characterized the function of StPBS1 in potato immunity and provide a biotechnology control method for PVY via transformation of decoy-engineered StPBS1NIa .