RESUMO
STING (stimulator of interferon genes) is a cytosolic sensor for cyclic dinucleotides and also an adaptor molecule for intracellular DNA receptors. Although STING has important functions in the host defense against pathogens and in autoimmune diseases, its physiological relevance in intestinal homeostasis is largely unknown. In this study, we show that STING-/- mice presented defective protective mechanisms of intestinal mucosa, including decreased number of goblet cells, diminished mucus production, and lower levels of secretory IgA, when compared with wild-type (WT) mice. Fecal content and microbiota DNA could activate STING, indicating a role of this molecule in gut. Microbiota composition was altered in STING-/- mice toward a more inflammatory profile, evidencing a reduction in the Allobacolum and Bifidobacterium groups along with increase in Disulfovibrio bacteria. Absence of STING lead to decrease in induced intraepithelial lymphocytes (IEL) and to increase in group 1 innate lymphoid cell (ILC1) as well as ILC3 frequencies and decrease in ILC2 in the colon. Development and function of Foxp3+ and LAP+ regulatory T cells were also compromised in STING-/- mice. Moreover, these mice were highly susceptible to dextran sodium sulfate-induced colitis, T-cell-induced colitis, and enteric Salmonella typhimurium infection when compared with WT animals. Therefore, our results identify an important role of STING in maintaining gut homeostasis and also a protective effect in controlling gut inflammation.
Assuntos
Colite/imunologia , Microbioma Gastrointestinal/fisiologia , Mucosa Intestinal/imunologia , Intestinos/fisiologia , Linfócitos/imunologia , Proteínas de Membrana/metabolismo , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Linfócitos T Reguladores/imunologia , Animais , Colite/induzido quimicamente , Colite/genética , Sulfato de Dextrana , Feminino , Fatores de Transcrição Forkhead/metabolismo , Homeostase , Imunidade Inata , Imunoglobulina A Secretora/sangue , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Salmonella/genética , Células Th1/imunologiaRESUMO
This study evaluated the chemical and genetic diversity of high-seed-yield sorghum germplasms from Korea, the United States, and South Africa. We identified significant differences in the chemical contents of whole plants at the heading stage in all cultivars, including differences in crude protein, fat, fiber, ash, neutral detergent fiber, acid detergent fiber, mineral, and fatty acid contents. Our results suggest that Banwoldang is the most appropriate cultivar for roughage because of its high protein yield. We identified significant differences in the tannin, flavonoid, amylose, mineral, crude fat, fatty acid, and 3-deoxyanthocyanin contents in the whole grain from all cultivars, but not in the mineral or crude fat contents. Tannin levels were generally low. IS645 contained the highest levels of flavonoids and linolenic acid compounds, and Moktak had the highest amylose and deoxyanthocyanidin content in the grain. To assess genetic diversity, we used 10 simple sequence repeat (SSR) primer sets to identify 38 alleles with 3-8 alleles per locus. Based on phylogenetic analysis of the SSR markers, the sorghum cultivars were divided into three major groups. Comparison of clusters based on chemical compositions with those based on SSRs showed that the groups formed by the three native Korean cultivars clustered similarly in molecular dendrograms. Association analysis was conducted for the 10 SSR marker; 48 chemical and growth traits were present for two marker traits (seed color and whole plant fatty acid content) with significant marker-trait associations. These markers could be used to select sorghum cultivars for breeding programs.
Assuntos
Loci Gênicos , Variação Genética , Filogenia , Sementes/genética , Sorghum/genética , Alelos , Antocianinas/metabolismo , Cruzamentos Genéticos , Ácidos Graxos/metabolismo , Flavonoides/metabolismo , Repetições de Microssatélites , Melhoramento Vegetal , Proteínas de Plantas/metabolismo , República da Coreia , Sementes/metabolismo , Sorghum/classificação , Sorghum/metabolismo , África do Sul , Taninos/metabolismo , Estados UnidosRESUMO
Under certain circumstances, transposable elements (TE) can create or reverse mutations and alter the genome size of a cell. Sorghum (Sorghum bicolor L.) is promising for plant transposon tagging due to its small genome size and its low content of repetitive DNA. We developed a marker system based on targeted region amplification polymorphisms (TE-TRAP) that uses the terminal inverted repeats (TIRs) of transposons. A total of 3816 class 2 transposons belonging to the PIF/Harbinger family were identified from the whole sorghum genome that produced five primers, including eight types of TIRs. To define the applicability and utilization of TE-TRAP, we used 21 individuals that had been bred after ɤ-ray irradiation. In total, 31 TE-TRAP, 16 TD, and 21 AFLP primer combinations generated 1133, 223, and 555 amplicons, respectively. The percent polymorphic marker was 62.8, 51.1, and 59.3% for the TE-TRAP, TD, and AFLP markers, respectively. Phylogenetic and principal component analyses revealed that TE-TRAP divided the 21 individuals into three groups. Analysis of molecular variance suggested that TE-TRAP had a higher level of genetic diversity than the other two marker systems. After verifying the efficiency of TE-TRAP, 189 sorghum individuals were used to investigate the associations between the markers and the ɤ-ray doses. Two significant associations were found among the polymorphic markers. This TE-based method provides a useful marker resource for mutation breeding research.
Assuntos
Elementos de DNA Transponíveis/genética , Filogenia , Melhoramento Vegetal , Sorghum/genética , Relação Dose-Resposta à Radiação , Raios gama , Marcadores Genéticos , Genoma de Planta/efeitos da radiação , Mutação , Sorghum/crescimento & desenvolvimento , Sorghum/efeitos da radiaçãoRESUMO
Comparative genomic hybridization (CGH) is a powerful tool used to analyze changes in copy number, polymorphisms, and structural variations in the genome. Gene copy number variation (CNV) is a common form of natural diversity in the genome, which can create new genes and alter gene structure. Thus, CNVs may influence phenotypic variation and gene expression. In this study, to detect CNVs, we irradiated rice seeds with gamma rays (300 Gy) and selected two dwarf mutagenized plants, GA-III-189 and -1052, in the M3 generation. These plants were subjected to CGH analysis using Agilent's RICE CGH array. Most of the CNVs identified were less than 10 kb in length. We detected 90 amplified and 18 deleted regions in GA-III-189, and 99 amplified and 11 deleted regions in GA-III-1052. Of note, CNVs were located on chromosome 12 in both GA-III-189 and -1052, which contained 39 commonly amplified regions in 29 genes. The commonly amplified genes included six genes encoding F-box domain-containing proteins. Alterations in these F-box domain-containing genes were confirmed by quantitative RT-PCR. Integration of CGH and gene expression data identified copy number aberrations and novel genes potentially involved in the dwarf phenotype. These CGH and gene expression data may be useful for uncovering the mechanisms underlying the dwarf phenotype.
Assuntos
Hibridização Genômica Comparativa , Raios gama , Mutação/efeitos da radiação , Oryza/genética , Oryza/efeitos da radiação , Variações do Número de Cópias de DNA , Raios gama/efeitos adversos , Expressão Gênica , Estudos de Associação Genética , FenótipoRESUMO
This study was designed to assess the role of bacteriophage P22 in the adhesion, invasion, intracellular survival of, and cellular immune response to Salmonella Typhimurium in intestinal epithelial INT-407 and chicken macrophage-like HD11 cells. The ability of S. Typhimurium to adhere, invade, and survive to INT-407 and HD11cells was evaluated under Salmonella infection alone (control), phage treatment followed by Salmonella infection (PS), Salmonella infection followed by phage treatment (SP), and a combination treatment with Salmonella and phage (S+P). The number of S. Typhimurium associated on INT-407 cells was reduced from 4.2 to 2.7 log cfu/cm2 by phage treatment (SP). The number of intracellular S. Typhimurium within INT-407 cells was significantly reduced to below the detection limit (0.7 log cfu/cm2) compared with the control (3.4 log cfu/cm2). S. Typhimurium remained inside HD11 cells at 49% and 17% levels in the absence and presence of phages, respectively, at 24 h post-infection (hpi). The expression levels of IFN-g, IL-10, IL-1b, IL-6, IL-8, iNOS, and IL-12 increased in HD11 cells regardless the absence and presence of phages, while those of IL-16, TLR2-1, TLR3, and TLR7 were decreased at 0 and 24 hpi. This study sheds new light on our understanding of the role of phages in Salmonella adhesion, invasion, survival, and cellular immune responses.(AU)
Assuntos
Animais , Salmonella typhimurium , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Células Epiteliais/microbiologiaRESUMO
This study was designed to assess the role of bacteriophage P22 in the adhesion, invasion, intracellular survival of, and cellular immune response to Salmonella Typhimurium in intestinal epithelial INT-407 and chicken macrophage-like HD11 cells. The ability of S. Typhimurium to adhere, invade, and survive to INT-407 and HD11cells was evaluated under Salmonella infection alone (control), phage treatment followed by Salmonella infection (PS), Salmonella infection followed by phage treatment (SP), and a combination treatment with Salmonella and phage (S+P). The number of S. Typhimurium associated on INT-407 cells was reduced from 4.2 to 2.7 log cfu/cm2 by phage treatment (SP). The number of intracellular S. Typhimurium within INT-407 cells was significantly reduced to below the detection limit (0.7 log cfu/cm2) compared with the control (3.4 log cfu/cm2). S. Typhimurium remained inside HD11 cells at 49% and 17% levels in the absence and presence of phages, respectively, at 24 h post-infection (hpi). The expression levels of IFN-g, IL-10, IL-1b, IL-6, IL-8, iNOS, and IL-12 increased in HD11 cells regardless the absence and presence of phages, while those of IL-16, TLR2-1, TLR3, and TLR7 were decreased at 0 and 24 hpi. This study sheds new light on our understanding of the role of phages in Salmonella adhesion, invasion, survival, and cellular immune responses.