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Ustilago esculenta, resembling a fungal endophyte in Zizania latifolia, inhibits the host plant flowering and induces the host stems to swell and form edible galls. It is well believed that when and how the fungus infects and proliferates in the host plants during the host development is of importance in the edible gall formation. Mitogen-activated protein kinases (MAPKs) have been found to play an important role in sensing environment cues and regulating infection. Two MAPK genes UeKpp2 and UeKpp6 from U. esculenta were cloned and suggested to be involved in the Fus3/Kss1 pathway by a phylogenetic analysis with the neighbor-joining method. Quantitative RT-PCR (qRT-PCR) analyses indicated that expression of UeKpp2 and UeKpp6 were induced during mating and infection processes, and their expression patterns displayed differentially under different carbon and nitrogen sources. In addition, subcellular localization of UeKpp2 or UeKpp6 fused with the reporter green fluoresce protein was observed by confocal laser scanning microscope, and yeast two-hybrid assays were carried out. Results showed that both UeKpp2 and UeKpp6 were located in cytoplasm and interacted with UePrf1, indicating their involvement in hyphal growth and host–pathogen regulation. Only UeKpp2 but not UeKpp6 interacted with the upstream MAPK kinase UeFuz7, implying an additional MAPK pathway, in which UeKpp6 involved, existed.Electronic supplementary materialThe online version of this article (10.1007/s00284-018-1483-3) contains supplementary material, which is available to authorized users.

Ustilago esculenta, an obligate parasite of Zizania latifolia, is a typical dimorphic fungus which induces host stem swelling and inhibits host inflorescence development, but is not found in host leaves. Previous studies have shown that dimorphic switching is essential for fungal pathogenicity and is regulated by protein kinase A and mitogen-activated protein kinase (MAPK) signaling pathways that are integrated by Prf1 in Ustilago maydis. In this study we identified a Prf1 homolog in U. esculenta, designated UePrf1, encoding 830 amino acids with a conserved high mobility group domain located between amino acids 124 and 195. UePrf1 was upregulated during the mating process, which induces dimorphism in U. esculenta. In vitro, UePrf1 mutants showed defects in the mating process, including cell fusion and hyphal growth. UePrf1 mutants also show reduced expression of a genes, even during the cell fusion process. Additionally, the defect in hyphal growth of the UeKpp2 and UeKpp6 mutants (MAPK signaling pathway mutants) was partially counteracted by UePrf1 overexpression, along with induced b gene expression. These results provide evidence that UePrf1 is a key factor coordinating dimorphism in U. esculenta and suggest a conserved role for UePrf1 in the regulation of the a and b genes.

BackgroundBreast cancer, a malignant disorder, occurs in epithelial tissue of the breast glands and ducts. Endocrine therapy is commonly applied as an important adjuvant treatment for breast cancer, but it usually induces a variety of side effects. Chinese Medicines (CM) has therapeutic effect on reducing adverse effects of the endocrine therapy in many clinical studies. But strong evidence is still limited on the efficacy and safety of CM combined western medicines (CM-WM) for breast cancer.ObjectiveTo study the efficacy and safety of CM-WM as an adjuvant treatment for reducing side effects induced by endocrine therapy in breast cancer patients.MethodWe searched relevant clinical studies in PubMed and the Chinese National Knowledge Infrastructure (CNKI) databases up to February 28, 2021 and only Randomized Controlled Trials (RCTs) were included. There were no limitations on the languages. We extracted data from the included RCTs, assessed study quality, conducted meta-analyses by RevMan 5.4 and compared the pooled Risk Ratios (RR) or Mean Difference (MD) with 95% CIs.ResultsIn total 28 trials involving 1,926 participants were included. Six RCTs compared CM-WM with CM placebo-WM, while 22 RCTs compared CM-WM with WM alone. No study compared CM-WM with no treatment. Meta-analysis showed that CM-WM treatment significantly improved quality of life (MD = 0.73, 95% CI = 0.11–1.35, P = 0.02) when compared with CM placebo-WM treatment. When compared with WM treatment alone, CM-WM treatment significantly improved bone mineral density (MD = 0.24, 95% CI = 0.13–0.35, P <0.0001), TCM syndrome score (MD = −5.39, 95% CI = −8.81 to −1.97, P = 0.0002), Kupperman Scale (MD = 0.24, 95% CI = −2.76 to −1.94, P <0.0001), Karnofsky Performance Scale (MD = 3.76, 95% CI = 1.64–5.88, P = 0.0005), quality of life (MD = 3.01, 95% CI = 1.00–5.02, P = 0.003), and pain relief (MD = 2.10, 95% CI = 0.72–3.48, P <0.0001). Compared with WM, CM-WM significantly decreased incidence of TCM symptoms (nausea, vomiting, fatigue, etc.) (RR = 1.60, 95% CI = 1.40–1.84, P <0.0001). For safety, serum calcium, estradiol, ALP, and blood CD3, CD4 and CD8 counts were not significantly difference between two treatments (P >0.05). Serious side effects or reactions were not reported in all included studies.ConclusionThe adjunctive use of CM reduced the endocrine therapy associated adverse events, including bone mineral density loss, perimenopausal symptoms, poor quality of life, pain and impaired immune function. But large-scale and high quality RCTs are needed to support the application of CM-WM therapy.

Background Ustilago esculenta , a typical dimorphic fungus could infect Zizania latifolia and induce host stem swollen to form an edible vegetable called Jiaobai in China. The strains differentiation especially in the mating ability and pathogenicity is closely related to different phenotypes of Jiaobai formed in the fields. Dimorphic switching, a tightly regulated processes, is essential for the pathogenetic development of dimorphic fungi. In responses to environment cues, dimorphic switching can be activated through two conserved cell signaling pathways-PKA and MAPK pathways. Previous study indicated that exogenous arginine could induce hyphal formation in several dimorphic fungi through hydrolysis by arginase, but inhibit the dimorphic transition of U. esculenta . We conducted this study to reveal the function of arginine on dimorphic transition of U. esculenta . Results In this study, we found that arginine, but not its anabolites, could slow down the dimorphic transition of U. esculenta proportionally to the concentration of arginine. Besides, UeArginase , predicated coding arginase in U. esculenta was cloned and characterized. UeArginase mutants could actually increase the content of endogenous arginine, and slow down the dimorphic transition on either nutritious rich or poor medium. Either adding exogenous arginine or UeArginase deletion lead to down regulated expressions of UePkaC , UePrf1 , mfa1.2 , mfa2.1 , pra1 and pra2 , along with an increased content of arginine during mating process. Conclusion Results of this study indicated a direct role of arginine itself on the inhibition of dimorphic transition of U. esculenta , independent of its hydrolysis by UeArginase. Electronic supplementary material The online version of this article (10.1186/s12866-019-1588-2) contains supplementary material, which is available to authorized users.