ABSTRACT
Under salt stress, recretohalophyte Plumbago auriculata tetraploids enhance salt tolerance by increasing selective secretion of Na+ compared with that in diploids, although the mechanism is unclear. Using non-invasive micro-test technology, the effect of salt gland Ca2+ content on Na+ and K+ secretion were investigated in diploid and tetraploid P. auriculata under salt stress. Salt gland Ca2+ content and secretion rates of Na+ and K+ were higher in tetraploids than in diploids under salt stress. Addition of exogenous Ca2+ increased the Ca2+ content of the salt gland in diploids and is accompanied by an increase in the rate of Na+ and K+ secretion. With addition of a Ca2+ channel inhibitor, diploid salt glands retained large amounts of Ca2+, leading to higher Ca2+ content and Na+ secretion rate than those of tetraploids. Inhibiting H2O2 generation and H+-ATPase activity altered Na+ and K+ secretion rates in diploids and tetraploids under salt stress, indicating involvement in regulating Na+ and K+ secretion. Our results indicate that the increased Na+ secretion rate of salt gland in tetraploids under salt stress was associated with elevated Ca2+ content in salt gland.
ABSTRACT
"Heteromorphic self-incompatibility" (HetSI) in plants is a mechanism of defense to avoid self-pollination and promote outcrossing. However, the molecular mechanism underlying HetSI remains largely unknown. In this study, RNA-seq was conducted to explore the molecular mechanisms underlying self-compatible (SC, "T × P" and "P × T") and self-incompatible (SI, "T × T" and "P × P") pollination in the two types of flowers of Plumbago auriculata Lam. which is a representative HetSI plant. By comparing "T × P" vs. "T × T", 3773 (1407 upregulated and 2366 downregulated) differentially expressed genes (DEGs) were identified, 1261 DEGs between "P × T" and "P × P" (502 upregulated and 759 downregulated). The processes in which these DEGs were significantly enriched were "MAPK (Mitogen-Activated Protein Kinases-plant) signaling pathway", "plant-pathogen interaction","plant hormone signal transduction", and "pentose and glucuronate interconversion" pathways. Surprisingly, we discovered that under various pollination conditions, multiple notable genes that may be involved in HetSI exhibited distinct regulation. We can infer that the HetSI strategy might be unique in P. auriculata. It was similar to "sporophytic self-incompatibility" (SSI) but the HetSI mechanisms in pin and thrum flowers are diverse. In this study, new hypotheses and inferences were proposed, which can provide a reference for crop production and breeding.
ABSTRACT
BACKGROUND: Innate immune memory of macrophages is closely linked to histone modifications. While various studies have demonstrated that the polysaccharide of Asparagus cochinchinensis (Lour.) Merr (ACMP), extracted through alcohol-alkali extraction, enhances macrophages' non-specific immune function; no literature currently addresses whether ACMP's regulatory effect is related to innate immune memory and histone modification. PURPOSE: This study aims to investigate if ACMP induces innate immune memory emergence in macrophages via pattern recognition receptor (PRR). STUDY DESIGN: After co-incubating different doses of ACMP with RAW264.7 cells and BMDM cells, we observed changes in signaling pathways related to PRR and assessed the presence of innate immune memory phenomenon in the cells. METHODS: We observed the morphological characteristics of the ACMP using a scanning electron microscope, infrared spectrum, and HPLC pre-column derivatization method. We used q-PCR, Western blot, RNA-seq, and CUT&Tag-seq methods to examine ACMP's regulation of macrophage immune response and innate immune memory and explored its specific mechanism. RESULTS: ACMP, primarily composed of Man, GlcN, Rha, Fuc, GalA, Xyl, Glc, Gal, Ara, and, exhibited a molar ratio of each monosaccharide (1.41: 0.35: 0.49: 0.18: 1.00: 97.12: 0.36: 3.58: 1.14). ACMP regulated immunological function in macrophages through the TLR4-MAPK-JNK/p38/ERK pathway. ACMP induced elevated levels of chromosomal H3K4me1, enhancing TNF-α, IL-1ß, and other genes' responsiveness, allowing macrophages to develop innate immune memory to ACMP stimulation. CONCLUSION: This study first time demonstrates that ACMP regulates immunological function through the TLR4-MAPK-JNK/ERK/p38 signaling pathway, distinct from prior reports. ACMP induces innate immune memory in macrophages in response to its immune stimulation by promoting increased H3K4me1 on chromosomes. This mechanism may be crucial in how plant polysaccharides regulate macrophages and the body's immune function.
Subject(s)
Aminopyridines , Epigenetic Memory , Toll-Like Receptor 4 , Humans , Male , Toll-Like Receptor 4/metabolism , Histone Code , Signal Transduction , Macrophages , Polysaccharides/pharmacology , ImmunityABSTRACT
Ammonia stress and nitrite stress can induce immune depression and oxidative stress in Litopenaeus vannami (L. vannamei). Earlier reports showed that L. vannamei immunity, resistance to ammonia stress, and resistance to nitrite stress improved after Tian-Dong-Tang-Gan Powder (TDTGP) treatment, but the mechanism is not clear. In this study, three thousand L. vannamei were fed different doses of TDTGP for 35 days and then subjected to ammonia and nitrite stress treatments for 72 h. Transcriptome and 16-Seq ribosomal RNA gene sequencing (16S rRNA-seq) were used to analyze hepatopancreas gene expression and changes in gut microbiota abundance in each group. The results showed that after TDTGP treatment, hepatopancreas mRNA expression levels of immunity- and antioxidant-related genes were increased, the abundance of Vibrionaceae in the gut microbiota was decreased, and the abundance of Rhodobacteraceae and Flavobacteriaceae was increased. In addition, after TDTGP treatment, the effects of ammonia and nitrite stress on the mRNA expression of Pu, cat-4, PPAF2, HO, Hsp90b1, etc. were reduced and the disruption of the gut microbiota was alleviated. In short, TDTGP can regulate the immunity and antioxidant of L. vannamei by increasing the expression levels of immunity- and antioxidant-related genes and regulating the abundance of Rhodobacteraceae and Flavobacteriaceae in the gut microbiota.
ABSTRACT
Quercitrin is a kind of flavonoid that is found in many plants; it has good antioxidant activity, and can regulate oxidative stress induced by Pseudorabies virus (PRV)-infected cells. In this study, the secretion of reactive oxygen species (ROS) induced by PRV infection was detected by flow cytometry, and RNA expression profiles of the 3D4/2 cells were produced and analyzed by sequenced GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes); the sequencing results were verified by RT-qCR. The results showed that the secretion of ROS induced by PRV infection in 3D4/2 cells could be significantly decreased by quercitrin. The differentially expressed 1055 mRNA, 867 lncRNA, 99 miRNA, and 69 circRNA were detected between the control group and the PRV infection group. The differentially expressed 1202 mRNA, 785 lncRNA, 115 miRNA, and 79 circRNA were found between the PRV+ quercitrin group and the control group. The differentially expressed 357 mRNA, 69 lncRNA, 111 miRNA, and 81 circRNA were obtained between the PRV+ quercitrin group and the PRV group. The significantly differentially expressed mRNAs were mainly involved in cell metabolism, regulatory protein phosphorylation, protein phosphorylation, antioxidation, regulatory phosphorylation, and so on. Among them, the mRNAs related to antioxidant response and oxidative stress were thioredoxin-interacting protein (TXNIP) and nitric oxide synthase 2 (NOS2). According to the network diagram of lncRNA-miRNA-mRNA, two targeted miRNA (ssc-miR-450c-3p and novel-m0400-3p) relationships with TXNIP and NOS2 were screened. This study provides a scientific foundation for further research for the function of quercitrin in anti-virus-induced oxidative stress.
