RESUMEN
Mesembryanthemum crystallinum L. (ice plant) develops salt tolerance during the transition from the juvenile to the adult stage through progressive morphological, physiological, biochemical, and molecular changes. Myo -inositol is the precursor for the synthesis of compatible solute D-pinitol and promotes Na+ transport in ice plants. We previously showed that supplying myo -inositol to 9-day-old seedlings alleviates salt damage by coordinating the expression of genes involved in inositol synthesis and transport, affecting osmotic adjustment and the Na/K balance. In this study, we examined the effects of myo -inositol on physiological parameters and inositol-related gene expression in early- and late-stage juvenile plants. The addition of myo -inositol to salt-treated, hydroponically grown late juvenile plants had no significant effects on growth or photosynthesis. In contrast, supplying exogenous myo -inositol to salt-treated early juvenile plants increased leaf biomass, relative water content, and chlorophyll content and improved PSII activity and CO2 assimilation. The treatment combining high salt and myo -inositol synergistically induced the expression of myo -inositol phosphate synthase (INPS ), myo -inositol O -methyltransferase (IMT ), and inositol transporters (INTs ), which modulated root-to-shoot Na/K ratio and increased leaf D-pinitol content. The results indicate that sufficient myo -inositol is a prerequisite for high salt tolerance in ice plant.
Asunto(s)
Mesembryanthemum , Plantas Tolerantes a la Sal , Plantas Tolerantes a la Sal/metabolismo , Mesembryanthemum/genética , Mesembryanthemum/metabolismo , Tolerancia a la Sal , Inositol/metabolismoRESUMEN
Myo-inositol and its metabolic derivatives such as pinitol, galactinol, and raffinose affect growth and development and are also involved in stress adaptation. Previous studies have identified myo-inositol transporters (INTs) as transporters of Na+ from root to shoot in the halophyte ice plant (Mesembryanthemum crystallinum). We found that the supply of myo-inositol could alleviate the dehydration effects of salt-stressed ice plant seedlings by decreasing the Na/K ratio in roots and increasing the Na/K ratio in shoots. Analyses of the uptake of exogenous myo-inositol revealed that ice plant seedlings contained intrinsic high-affinity transporters and inducible low-affinity uptake systems. The presence of Na+ facilitated both high- and low-affinity myo-inositol uptake. Six INT genes were identified from the ice plant transcriptome and named McINT1a, 1b, 2, 4a, 4b, and 4c, according to the classification of the Arabidopsis INT family. In seedlings treated with myo-inositol, salt, or myo-inositol plus salt, the expression patterns of all McINT members differed in shoot and root, which indicates organ-specific regulation of McINTs by salt and myo-inositol. The expression of McINT2, 4a, 4b, and 4c was induced by salt stress in shoot and root, but that of McINT1a and 1b was salt-induced only in shoot. The expression of pinitol biosynthesis gene IMT1 was induced by salt and myo-inositol, and their combination had a synergistic effect on the accumulation of pinitol. Supply of myo-inositol to salt-treated seedlings alleviated the detrimental effects by maintaining a low root Na/K ratio and providing precursors for the synthesis of compatible solute to maintain the osmotic balance.
Asunto(s)
Mesembryanthemum , Regulación de la Expresión Génica de las Plantas , Inositol , Tolerancia a la Sal , Plantas Tolerantes a la Sal , Plantones/genéticaRESUMEN
To avoid inducing immune and physiological responses in insect hosts, parasitoid wasps have developed several mechanisms to inhibit them during parasitism, including the production of venom, specialized wasp cells, and symbioses with polydnaviruses (PDVs). These mechanisms alter the host physiology to give the wasp offspring a greater chance of survival. However, the molecular mechanisms for most of these alterations remain unclear. In the present study, we applied next-generation sequencing analysis and identified several miRNAs that were encoded in the genome of Snellenius manilae bracovirus (SmBV), and expressed in the host larvae, Spodoptera litura, during parasitism. Among these miRNAs, SmBV-miR-199b-5p and SmBV-miR-2989 were found to target domeless and toll-7 in the host, which are involved in the host innate immune responses. Microinjecting the inhibitors of these two miRNAs into parasitized S. litura larvae not only severely decreased the pupation rate of Snellenius manilae, but also restored the phagocytosis and encapsulation activity of the hemocytes. The results demonstrate that these two SmBV-encoded miRNAs play an important role in suppressing the immune responses of parasitized hosts. Overall, our study uncovers the functions of two SmBV-encoded miRNAs in regulating the host innate immune responses upon wasp parasitism.
Asunto(s)
Interacciones Huésped-Parásitos/inmunología , MicroARNs/metabolismo , Polydnaviridae/metabolismo , Spodoptera/inmunología , Avispas/virología , Animales , Femenino , Genoma Viral , Inmunidad Celular , Inmunidad Innata , MicroARNs/antagonistas & inhibidores , Fagocitosis , Spodoptera/parasitologíaRESUMEN
Although the modulation of host physiology has been interpreted as an essential process supporting baculovirus propagation, the requirement of energy supply for host antivirus reactions could not be ruled out. Our present study showed that metabolic induction upon AcMNPV (budded virus) infection of Bombyx mori stimulated virus clearance and production of the antivirus protein, gloverin. In addition, we demonstrated that adenosine receptor signaling (AdoR) played an important role in regulating such metabolic reprogramming upon baculovirus infection. By using a second lepidopteran model, Spodoptera frugiperda Sf-21 cells, we demonstrated that the glycolytic induction regulated by adenosine signaling was a conservative mechanism modulating the permissiveness of baculovirus infection. Another interesting finding in our present study is that both BmNPV and AcMNPV infection cause metabolic activation, but it appears that BmNPV infection moderates the level of ATP production, which is in contrast to a dramatic increase upon AcMNPV infection. We identified potential AdoR miRNAs induced by BmNPV infection and concluded that BmNPV may attempt to minimize metabolic activation by suppressing adenosine signaling and further decreasing the host's anti-baculovirus response. Our present study shows that activation of energy synthesis by adenosine signaling upon baculovirus infection is a host physiological response that is essential for supporting the innate immune response against infection.
Asunto(s)
Bombyx/metabolismo , Bombyx/virología , Infecciones por Virus ADN/metabolismo , Nucleopoliedrovirus/fisiología , Receptores Purinérgicos P1/metabolismo , Adenosina/metabolismo , Adenosina Trifosfato/biosíntesis , Animales , Infecciones por Virus ADN/virología , Desoxiglucosa/farmacología , Metabolismo Energético , Glucólisis/efectos de los fármacos , Glucólisis/genética , Interacciones Huésped-Patógeno/inmunología , Proteínas de Insectos/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Receptores Purinérgicos P1/genética , Células Sf9 , Spodoptera , Transfección , Replicación Viral/efectos de los fármacosRESUMEN
PURPOSE: The aim of this study was to investigate whether any of the single-nucleotide polymorphisms (SNPs) in the POR gene were significantly associated with CYP activity and expression, and could contribute to the total variability in stable warfarin maintenance doses in Han Chinese. METHODS: A total of 408 patients treated at the First Affiliated Hospital of Sun Yat-Sen University were eligible for the study and had attained a stable warfarin maintenance dose at the start of the investigation. Demographics, warfarin maintenance doses, and concomitant medications were documented. Genomic DNA was extracted from peripheral blood samples and genotyped for ten SNPs (CYP 2C9*2 and *3, CYP4F2 rs2108622, VKORC1 -1639C>T, and potential POR genes of rs10239977, rs3815455, rs41301394, rs56256515, rs1057868, and rs2286823) using the Sequenom MassARRAY genotyping system. RESULTS: A predictive model of warfarin maintenance dose was established and indicated that age, gender, body surface area, aspirin use, CYP2C9*3, CYP4F2 rs2108622, VKORC1 -1639C>T, and POR*37 831-35C>T accounted for 42.4 % of dose variance in patients undergoing anticoagulant treatment. The contribution of POR*37 831-35C>T to warfarin dose variation was only 3.9 %. CONCLUSIONS: For the first time, the SNP POR*37 831-35C>T was confirmed as a minor but statistically significant factor associated with interindividual variation in warfarin maintenance dose in Han Chinese. The POR*37 gene polymorphism should be considered in future algorithms for faster and more reliable achievement of stable warfarin maintenance doses.