The production of transgenic citrus plants from adult tissues is difficult because of low regeneration and transformation rates. To increase the transformation efficiency of adult citrus tissues, an improved protocol involving adult Citrus sinensis Osbeck ‘Tarocco’ blood orange tissues was developed. Explants were pre-incubated in a liquid medium prior to infection by Agrobacterium tumefaciens. Plant materials were also incubated on callus-induction medium supplemented with various combinations of cytokinin (Cyt) and kanamycin (Kan). An appropriate pre-incubation of the explants increased the transformation efficiency of adult tissues. During the callus-induction period, the Cyt type and Kan concentration had the largest and smallest effects on the transformation efficiency, respectively. The most effective combination of plant growth regulator and Kan for the transformation of ‘Tarocco’ blood orange tissues was 2 mg L−1 2-isopentenyl adenine and 50 mg L−1 Kan. The transformation efficiency under the optimized conditions was 11.7%. A Southern blot analysis confirmed the integration of the transgene. These results indicated that the transformation efficiency of adult citrus tissues can be enhanced by optimizing the transformation conditions.
Previous studies show that the proliferation of human mesangial cells (HMCs) played a significant part in the pathogenesis of Henoch‐Schönlein purpura nephritis (HSPN). The aim of this study was to explore the proliferation of HMCs induced by IgA1 isolated from the sera of HSP patients. HMCs were cultured in three different types of media, including IgA1 from patients with HSP (HSP IgA1 group), healthy children (healthy IgA1 group) and medium (control group). The proliferation of HMCs incubated with IgA1 was determined by cell counting kit‐8 assay and bromodeoxyuridine incorporation. The expression of ERK1/2 and phosphatidylinositol 3 kinase/protein kinase B/mammalian targets of the rapamycin (PI3K/AKt/mTOR) signals and transferrin receptor (TfR/CD71) was detected with the methods of immunoblotting. The results indicated that the proliferation of HMCs significantly increased in the HSP IgA1 group compared with that in the control group or the healthy IgA1 group (P < 0.001). Moreover, we found that IgA1 isolated from HSP patients activated ERK and PI3K/AKt/mTOR signals, and markedly increased TfR/CD71 expression in HMCs. These effects induced by IgA1 isolated from patients with HSP were inhibited by human TfR polyclonal antibody (hTfR pAb) and soluble human transferrin receptor (sTfR), indicating that IgA1‐induced HMC proliferation and ERK1/2 and PI3K/AKt/mTOR activation were dependent on TfR/CD71 engagement. Altogether, these data suggested that TfR/CD71 overexpression and ERK1/2 and PI3K/AKt/mTOR activation were engaged in HMC proliferation induced by IgA1 from HSP patients, which might be related to the mesangial injury of HSPN. 相似文献
According to our previous results, resveratrol (RSV, 3, 5, 4-trihydroxystilbene), a naturally polyphenolic phytoalexin, could attenuate myocardial ischemia/reperfusion injury through up-regulation of vascular endothelial growth factor B (VEGF-B) in isolated rat heart or H9c2 cells. However, the molecular mechanism remains unclear. In this study, we investigated the protective effect of RSV on myocardial infarction (MI) in rats and further explored the underlying signal pathway after VEGF-B. Rats received RSV or normal saline by intragastric administration for 7 consecutive days and followed by subcutaneously isoproterenol (ISO) or normal saline injections for another 2 days. We found that RSV pretreatment prevented the unfavourable changes in HW/BW, HW/TL, infarct size, and cell apoptosis in ISO-treated rats. Moreover, superoxide and malondialdehyde (MDA) production were significantly reduced and superoxide dismutase (SOD) was increased by RSV in ISO-treated rats. Furthermore, it showed that RSV pretreatment increased VEGF-B, p-eNOS and p-AMPK expression, and NO production in ISO-treated rats. Using Neonatal Rat Ventricular Myocytes (NRVM), we found that VEGF-B siRNA could abolish the cardio-protective effect of RSV. The enhanced ratios of eNOS phosphorylation to eNOS expression induced by RSV were markedly reversed by VEGF-B siRNA in NRVM also. Meantime, we found that the effect of VEGF-B knock-down on eNOS activation was rescued by AMPK activator AICAR. L-NAME, a NOS inhibitor, could inhibit RSV enhanced eNOS phosphorylation but had no effect on VEGF-B expression in NRVM or in rats. Collectively, our results indicate that RSV exerts cardio-protection from ISO-induced myocardial infarction through VEGF-B/AMPK/eNOS/NO signalling pathway. 相似文献
Ankylosing spondylitis (AS) is a high disability and greatly destructive disease. In this study, we preliminarily studied the function and mechanism of bilobalide (BIL) on interleukin (IL)‐17‐induced inflammatory injury in ATDC5 cells. CCK‐8 and migration assays were used to detect the functions of IL‐7, BIL, and microRNA (miR)‐125a on cell viability and migration. The miR‐125a level was changed by transfection, and tested by real‐time quantitative polymerase chain reaction. Additionally, Western blot tested the levels of inflammatory factors (IL‐6 and tumor necrosis factor‐α), matrix metalloproteinases (MMPs), and pathway‐related proteins. Moreover, the enzyme‐linked immunosorbent assay also was used to detect inflammatory factor levels. IL‐7 was used to construct an inflammatory injury model in ATDC5 cells. Based on this, BIL inhibited IL‐17‐induced cell viability, migration, and expressions of inflammatory factors and MMPs. Furthermore, we found BIL negatively regulated miR‐125a, and the miR‐125a mimic could partly reverse the effects of BIL on IL‐17‐injury. Finally, we showed that BIL inhibited the c‐Jun N‐terminal kinase (JNK) and nuclear factor kappa B (NF‐κB) pathways, and the miR‐125a mimic had the opposite effect. BIL inhibited IL‐17‐induced inflammatory injury in ATDC5 cells by downregulation of miR‐125a via JNK and NF‐κB signaling pathways. 相似文献
Verticillium dahliae is a soil-borne fungus that causes vascular wilt on numerous plants worldwide. The fungus survives in the soil for up to 14 years by producing melanized microsclerotia. The protective function of melanin in abiotic stresses is well documented. Here, we found that the V. dahliae tetraspan transmembrane protein VdSho1, a homolog of the Saccharomyces cerevisiae Sho1, acts as an osmosensor, and is required for plant penetration and melanin biosynthesis. The deletion mutant ΔSho1 was incubated on a cellophane membrane substrate that mimics the plant epidermis, revealing that the penetration of ΔSho1 strain was reduced compared to the wild-type strain. Furthermore, VdSho1 regulates melanin biosynthesis by a signalling mechanism requiring a kinase-kinase signalling module of Vst50-Vst11-Vst7. Strains, ΔVst50, ΔVst7 and ΔVst11 also displayed defective penetration and melanin production like the ΔSho1 strain. Defects in penetration and melanin production in ΔSho1 were restored by overexpression of Vst50, suggesting that Vst50 lies downstream of VdSho1 in the regulatory pathway governing penetration and melanin biosynthesis. Data analyses revealed that the transmembrane portion of VdSho1 was essential for both membrane penetration and melanin production. This study demonstrates that Vst50-Vst11-Vst7 module regulates VdSho1-mediated plant penetration and melanin production in V. dahliae, contributing to virulence. 相似文献
Improving genetic resistance is a preferred method to manage Verticillium wilt of cotton and other hosts. Identifying host resistance is difficult because of the dearth of resistance genes against this pathogen. Previously, a novel candidate gene involved in Verticillium wilt resistance was identified by a genome-wide association study using a panel of Gossypium hirsutum accessions. In this study, we cloned the candidate resistance gene from cotton that encodes a protein sharing homology with the TIR-NBS-LRR receptor-like defence protein DSC1 in Arabidopsis thaliana (hereafter named GhDSC1). GhDSC1 expressed at higher levels in response to Verticillium wilt and jasmonic acid (JA) treatment in resistant cotton cultivars as compared to susceptible cultivars and its product was localized to nucleus. The transfer of GhDSC1 to Arabidopsis conferred Verticillium resistance in an A. thalianadsc1 mutant. This resistance response was associated with reactive oxygen species (ROS) accumulation and increased expression of JA-signalling-related genes. Furthermore, the expression of GhDSC1 in response to Verticillium wilt and JA signalling in A. thaliana displayed expression patterns similar to GhCAMTA3 in cotton under identical conditions, suggesting a coordinated DSC1 and CAMTA3 response in A. thaliana to Verticillium wilt. Analyses of GhDSC1 sequence polymorphism revealed a single nucleotide polymorphism (SNP) difference between resistant and susceptible cotton accessions, within the P-loop motif encoded by GhDSC1. This SNP difference causes ineffective activation of defence response in susceptible cultivars. These results demonstrated that GhDSC1 confers Verticillium resistance in the model plant system of A. thaliana, and therefore represents a suitable candidate for the genetic engineering of Verticillium wilt resistance in cotton. 相似文献
Colorectal cancer (CRC) is a common disease worldwide that is strongly associated with the gut microbiota. However, little is known regarding the gut microbiota after surgical treatment. 16S rRNA gene sequencing was used to evaluate differences in gut microbiota among colorectal adenoma patients, CRC patients, CRC postoperative patients and healthy controls by comparing gut microbiota diversity, overall composition and taxonomic signature abundance. The gut microbiota of CRC patients, adenoma patients and healthy controls developed in accordance with the adenoma-carcinoma sequence, with impressive shifts in the gut microbiota before or during the development of CRC. The gut microbiota of postoperative patients and CRC patients differed significantly. Subdividing CRC postoperative patients according to the presence or absence of newly developed adenoma which based on the colonoscopy findings revealed that the gut microbiota of newly developed adenoma patients differed significantly from that of clean intestine patients and was more similar to the gut microbiota of carcinoma patients than to the gut microbiota of healthy controls. The alterations of the gut microbiota between the two groups of postoperative patients corresponded to CRC prognosis. More importantly, we used the different gut microbiota as biomarkers to distinguish postoperative patients with or without newly developed adenoma, achieving an AUC value of 0.72. These insights on the changes in the gut microbiota of CRC patients after surgical treatment may allow the use of the microbiota as non-invasive biomarkers for the diagnosis of newly developed adenomas and to help prevent cancer recurrence in postoperative patients. 相似文献