RESUMEN
Sphingolipids are critically significant in a range of biological processes in animals, plants, and fungi. In mammalian cells, they serve as vital components of the plasma membrane (PM) in maintaining its structure, tension, and fluidity. They also play a key role in a wide variety of biological processes, such as intracellular signal transduction, cell polarization, differentiation, and migration. In plants, sphingolipids are important for cell development and for cell response to environmental stresses. In pathogenic fungi, sphingolipids are crucial for the initiation and the development of infection processes afflicting humans. However, our knowledge on the metabolism and function of the sphingolipid metabolic pathway of pathogenic fungi affecting plants is still very limited. In this review, we discuss recent developments on sphingolipid pathways of plant pathogenic fungi, highlighting their uniqueness and similarity with plants and animals. In addition, we discuss recent advances in the research and development of fungal-targeted inhibitors of the sphingolipid pathway, to gain insights on how we can better control the infection process occurring in plants to prevent or/and to treat fungal infections in crops.
Asunto(s)
Plantas , Esfingolípidos , Humanos , Animales , Esfingolípidos/química , Esfingolípidos/metabolismo , Plantas/metabolismo , Hongos/metabolismo , Transducción de Señal/fisiología , Membrana Celular/metabolismo , MamíferosRESUMEN
The cell cycle is pivotal to cellular differentiation in plant pathogenic fungi. Cell wall integrity (CWI) signaling plays an essential role in coping with cell wall stress. Autophagy is a degradation process in which cells decompose their components to recover macromolecules and provide energy under stress conditions. However, the specific association between cell cycle, autophagy and CWI pathway remains unclear in model pathogenic fungi Magnaporthe oryzae. Here, we have identified MoSwe1 as the conserved component of the cell cycle in the rice blast fungus. We have found that MoSwe1 targets MoMps1, a conserved critical MAP kinase of the CWI pathway, through protein phosphorylation that positively regulates CWI signaling. The CWI pathway is abnormal in the ΔMoswe1 mutant with cell cycle arrest. In addition, we provided evidence that MoSwe1 positively regulates autophagy by interacting with MoAtg17 and MoAtg18, the core autophagy proteins. Moreover, the S phase initiation was earlier, the morphology of conidia and appressoria was abnormal, and septum formation and glycogen degradation were impaired in the ΔMoswe1 mutant. Our research defines that MoSWE1 regulation of G1/S transition, CWI pathway, and autophagy supports its specific requirement for appressorium development and virulence in plant pathogenic fungi. Video Abstract.
Asunto(s)
Ascomicetos , Ciclo Celular , Autofagia , Pared CelularRESUMEN
Dihydroorotase (DHOase) is the third enzyme in the six enzymatic reaction steps of the endogenous pyrimidine nucleotide de novo biosynthesis pathway, which is a metabolic pathway conserved in both bacteria and eukaryotes. However, research on the biological function of DHOase in plant pathogenic fungi is very limited. In this study, we identified and named MoPyr4, a homologous protein of Saccharomyces cerevisiae DHOase Ura4, in the rice blast fungus Magnaporthe oryzae and investigated its ability to regulate fungal growth, pathogenicity, and autophagy. Deletion of MoPYR4 led to defects in growth, conidiation, appressorium formation, the transfer and degradation of glycogen and lipid droplets, appressorium turgor accumulation, and invasive hypha expansion in M. oryzae, which eventually resulted in weakened fungal pathogenicity. Long-term replenishment of exogenous uridine-5'-phosphate (UMP) can effectively restore the phenotype and virulence of the ΔMopyr4 mutant. Further study revealed that MoPyr4 also participated in the regulation of the Pmk1-MAPK signaling pathway, co-localized with peroxisomes for the oxidative stress response, and was involved in the regulation of the Osm1-MAPK signaling pathway in response to hyperosmotic stress. In addition, MoPyr4 interacted with MoAtg5, the core protein involved in autophagy, and positively regulated autophagic degradation. Taken together, our results suggested that MoPyr4 for UMP biosynthesis was crucial for the development and pathogenicity of M. oryzae. We also revealed that MoPyr4 played an essential role in the external stress response and pathogenic mechanism through participation in the Pmk1-MAPK signaling pathway, peroxisome-related oxidative stress response mechanism, the Osm1-MAPK signaling pathway and the autophagy pathway.
Asunto(s)
Autofagia , Proteínas Fúngicas , Oryza , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Oryza/microbiología , Virulencia/genética , Peroxisomas/metabolismo , Enfermedades de las Plantas/microbiología , Ascomicetos/patogenicidad , Ascomicetos/genética , Ascomicetos/enzimología , Sistema de Señalización de MAP Quinasas , Estrés OxidativoRESUMEN
Csn5 is subunit 5 of the COP9 signalosome (CSN), but the mechanism by which it strictly controls the pathogenicity of pathogenic fungi through autophagy remains unclear. Here, we found that Csn5 deficiency attenuated pathogenicity and enhanced autophagy in Magnaporthe oryzae. MoCSN5 knockout led to overubiquitination and overdegradation of MoTor (the core protein of the TORC1 complex [target of rapamycin]) thereby promoted autophagy. In addition, we identified MoCsn5 as a new interactor of MoAtg6. Atg6 was found to be ubiquitinated through linkage with lysine 48 (K48) in cells, which is necessary for infection-associated autophagy in pathogenic fungi. K48-ubiquitination of Atg6 enhanced its degradation and thereby inhibited autophagic activity. Our experimental results indicated that MoCsn5 promoted K48-ubiquitination of MoAtg6, which reduced the MoAtg6 protein content and thus inhibited autophagy. Aberrant ubiquitination and autophagy in ΔMocsn5 led to pleiotropic defects in the growth, development, stress resistance, and pathogenicity of M. oryzae. In summary, our study revealed a novel mechanism by which Csn5 regulates autophagy and pathogenicity in rice blast fungus through ubiquitination.
Asunto(s)
Ascomicetos , Virulencia , Proteínas , Ubiquitinación , AutofagiaRESUMEN
Septins play a key regulatory role in cell division, cytokinesis, and cell polar growth of the rice blast fungus (Magnaporthe oryzae). We found that the organization of the septin ring, which is essential for appressorium-mediated infection in M. oryzae, requires long-chain fatty acids (LCFAs), which act as mediators of septin organization at membrane interfaces. However, it is unclear how septin ring formation and LCFAs regulate the pathogenicity of the rice blast fungus. In this study, a novel protein was named MoLfa1 because of its role in LCFAs utilization. MoLfa1 affects the utilization of LCFAs, lipid metabolism, and the formation of the septin ring by binding with phosphatidylinositol phosphates (PIPs), thereby participating in the construction of penetration pegs of M. oryzae. In addition, MoLfa1 is localized in the endoplasmic reticulum (ER) and interacts with the ER-related protein MoMip11 to affect the phosphorylation level of Mps1. (Mps1 is the core protein in the MPS1-MAPK pathway.) In conclusion, MoLfa1 affects conidia morphology, appressorium formation, lipid metabolism, LCFAs utilization, septin ring formation, and the Mps1-MAPK pathway of M. oryzae, influencing pathogenicity.
Asunto(s)
Ascomicetos , Magnaporthe , Oryza , Septinas/metabolismo , Proteínas Fúngicas/metabolismo , Magnaporthe/fisiología , Citoesqueleto/metabolismo , Oryza/metabolismo , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/metabolismo , Regulación Fúngica de la Expresión GénicaRESUMEN
BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative therapy for hematologic malignancies and non-malignant disorders, such as aplastic anemia, fanconi anemia, and certain immune deficiencies. Post-transplantation kidney injury is a common complication and involves a wide spectrum of structural abnormalities, including glomerular (MSPGN, mesangial proliferative glomerulonephritis; FSGS, focal segmental glomerulosclerosis; MPGN, membranoproliferative glomerulonephritis; MCD, minimal change disease), vascular (TMA, thrombotic microangiopathy), and/or tubulointerstitial (TIN, tubulointerstitial nephritis; ATI, acute tubular injury). Renal biopsy is the gold-standard examination for defining multiple etiologies of kidney impairment. Although kidney injury following HSCT has been studied, little is known about the effects of allo-HSCT on renal pathology in pediatric patients. METHODS: We retrospectively analyzed renal biopsy specimens from children with kidney injury after allo-HSCT and correlated results with clinical data in the last 10 years. RESULTS: Among 25 children (18 males and 7 females), three patients had proteinuria indicating nephrotic syndrome (24-hour urinary total protein/weight > 50 mg/kg/d), nine patients had severely reduced estimated glomerular filtration rate (eGFR < 30 ml/min/1.73 m2) and four patients received kidney replacement therapy (KRT). The main pathologies identified from kidney biopsies were MSPGN (n = 12), FSGS (n = 12), MPGN (n = 5), TMA (n = 4), MCD (n = 3), diffuse glomerular fibrosis (DGF, n = 2), ATI and TIN, in isolation or combined with other pathologies. The median follow-up time was 16.5 (0.5 ~ 68.0) months. Three patients died of recurrent malignancy and/or severe infection, one child developed to end-stage renal disease (ESRD), six patients (24%) had elevated serum creatinine (SCr > 100µmol/l) and nine patients (36%) still had proteinuria. CONCLUSIONS: This study evaluates histomorphologic findings from kidney biopsies of pediatric recipients following allo-HSCT. Detailed evaluation of renal biopsy samples is helpful to elucidate the nature of renal insult, and may potentially identify treatable disease processes.
Asunto(s)
Glomerulonefritis Membranoproliferativa , Glomerulonefritis Membranosa , Glomeruloesclerosis Focal y Segmentaria , Trasplante de Células Madre Hematopoyéticas , Enfermedades Renales , Niño , Femenino , Humanos , Masculino , Biopsia/efectos adversos , Glomerulonefritis Membranoproliferativa/complicaciones , Glomerulonefritis Membranoproliferativa/patología , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/patología , Glomeruloesclerosis Focal y Segmentaria/complicaciones , Glomeruloesclerosis Focal y Segmentaria/patología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Riñón/patología , Proteinuria/complicaciones , Estudios RetrospectivosRESUMEN
Calcineurin, a key regulator of the calcium signaling pathway, is involved in calcium signal transduction and calcium ion homeostasis. Magnaporthe oryzae is a devastating filamentous phytopathogenic fungus in rice, yet little is known about the function of the calcium signaling system. Here, we identified a novel calcineurin regulatory-subunit-binding protein, MoCbp7, which is highly conserved in filamentous fungi and was found to localize in the cytoplasm. Phenotypic analysis of the MoCBP7 gene deletion mutant (ΔMocbp7) showed that MoCbp7 influenced the growth, conidiation, appressorium formation, invasive growth, and virulence of M. oryzae. Some calcium-signaling-related genes, such as YVC1, VCX1, and RCN1, are expressed in a calcineurin/MoCbp7-dependent manner. Furthermore, MoCbp7 synergizes with calcineurin to regulate endoplasmic reticulum homeostasis. Our research indicated that M. oryzae may have evolved a new calcium signaling regulatory network to adapt to its environment compared to the fungal model organism Saccharomyces cerevisiae.
Asunto(s)
Magnaporthe , Oryza , Virulencia/genética , Calcineurina/genética , Calcineurina/metabolismo , Proteínas Portadoras/metabolismo , Señalización del Calcio , Calcio/metabolismo , Magnaporthe/fisiología , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oryza/metabolismo , Enfermedades de las Plantas/microbiología , Esporas FúngicasRESUMEN
Magnaporthe oryzae is an important plant pathogen that causes rice blast. Hse1 and Vps27 are components of ESCRT-0 involved in the multivesicular body (MVB) sorting pathway and biogenesis. To date, the biological functions of ESCRT-0 in M. oryzae have not been determined. In this study, we identified and characterized Hse1 and Vps27 in M. oryzae. Disruption of MoHse1 and MoVps27 caused pleiotropic defects in growth, conidiation, sexual development and pathogenicity, thereby resulting in loss of virulence in rice and barley leaves. Disruption of MoHse1 and MoVps27 triggered increased lipidation of MoAtg8 and degradation of GFP-MoAtg8, indicating that ESCRT-0 is involved in the regulation of autophagy. ESCRT-0 was determined to interact with coat protein complex II (COPII), a regulator functioning in homeostasis of the endoplasmic reticulum (ER homeostasis), and disruption of MoHse1 and MoVps27 also blocked activation of the unfolded protein response (UPR) and autophagy of the endoplasmic reticulum (ER-phagy). Overall, our results indicate that ESCRT-0 plays critical roles in regulating fungal development, virulence, autophagy and ER-phagy in M. oryzae.
Asunto(s)
Magnaporthe , Oryza , Ascomicetos , Autofagia/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/metabolismo , VirulenciaRESUMEN
The development and pathogenicity of the fungus Magnaporthe oryzae, the causal agent of destructive rice blast disease, require it to perceive external environmental signals. Opy2, an overproduction-induced pheromone-resistant protein 2, is a crucial protein for sensing external signals in Saccharomyces cerevisiae. However, the biological functions of the homologue of Opy2 in M. oryzae are unclear. In this study, we identified that MoOPY2 is involved in fungal development, pathogenicity, and autophagy in M. oryzae. Deletion of MoOPY2 resulted in pleiotropic defects in hyphal growth, conidiation, germ tube extension, appressorium formation, appressorium turgor generation, and invasive growth, therefore leading to attenuated pathogenicity. Furthermore, MoOpy2 participates in the Osm1 MAPK pathway and the Mps1 MAPK pathway by interacting with the adaptor protein Mst50. The interaction sites of Mst50 and MoOpy2 colocalized with the autophagic marker protein MoAtg8 in the preautophagosomal structure sites (PAS). Notably, the ΔMoopy2 mutant caused cumulative MoAtg8 lipidation and rapid GFP-MoAtg8 degradation in response to nitrogen starvation, showing that MoOpy2 is involved in the negative regulation of autophagy activity. Taken together, our study revealed that MoOpy2 of M. oryzae plays an essential role in the orchestration of fungal development, appressorium penetration, autophagy and pathogenesis.
Asunto(s)
Magnaporthe , Oryza , Ascomicetos , Autofagia/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Magnaporthe/metabolismo , Oryza/microbiología , Enfermedades de las Plantas/microbiología , Esporas Fúngicas/metabolismo , Virulencia/genéticaRESUMEN
Magnaporthe oryzae is an important pathogen that causes a devastating disease in rice. It has been reported that the dual-specificity LAMMER kinase is conserved from yeast to animal species and has a variety of functions. However, the functions of the LAMMER kinase have not been reported in M. oryzae. In this study, we identified the unique LAMMER kinase MoKns1 and analyzed its function in M. oryzae. We found that in a MoKNS1 deletion mutant, growth and conidiation were primarily decreased, and pathogenicity was almost completely lost. Furthermore, our results found that MoKns1 is involved in autophagy. The ΔMokns1 mutant was sensitive to rapamycin, and MoKns1 interacted with the autophagy-related protein MoAtg18. Compared with the wild-type strain 70-15, autophagy was significantly enhanced in the ΔMokns1 mutant. In addition, we also found that MoKns1 regulated DNA damage stress pathways, and the ΔMokns1 mutant was more sensitive to hydroxyurea (HU) and methyl methanesulfonate (MMS) compared to the wild-type strain 70-15. The expression of genes related to DNA damage stress pathways in the ΔMokns1 mutant was significantly different from that in the wild-type strain. Our results demonstrate that MoKns1 is an important pathogenic factor in M. oryzae involved in regulating autophagy and DNA damage response pathways, thus affecting virulence. This research on M. oryzae pathogenesis lays a foundation for the prevention and control of M. oryzae.
Asunto(s)
Magnaporthe , Oryza , Ascomicetos , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulación Fúngica de la Expresión Génica , Oryza/metabolismo , Enfermedades de las Plantas , Esporas Fúngicas , Virulencia/genéticaRESUMEN
Plant diseases caused by fungi are one of the major threats to global food security and understanding the interactions between fungi and plants is of great significance for plant disease control. The interaction between pathogenic fungi and plants is a complex process. From the perspective of pathogenic fungi, pathogenic fungi are involved in the regulation of pathogenicity by surface signal recognition proteins, MAPK signaling pathways, transcription factors, and pathogenic factors in the process of infecting plants. From the perspective of plant immunity, the signal pathway of immune response, the signal transduction pathway that induces plant immunity, and the function of plant cytoskeleton are the keys to studying plant resistance. In this review, we summarize the current research progress of fungi-plant interactions from multiple aspects and discuss the prospects and challenges of phytopathogenic fungi and their host interactions.
Asunto(s)
Hongos , Plantas , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Plantas/microbiología , Factores de VirulenciaRESUMEN
BACKGROUND: Disorders of the metabolism and absorption of vitamin B12 can lead to decrease in activity of methionine synthetase and methylmalonate coenzyme A mutase (MMUT), which results in increased levels of methylmalonic acid and homocysteine in blood and urine. Often, combined methylmalonic acidemia (MMA) and homocysteinemia is misdiagnosed due to a lack of specific symptoms. The clinical manifestations are diverse, but proteinuria as the initial presentation is rare. CASE PRESENTATION: Two cases of MMA with homocysteinemia in children are reported. Proteinuria were a primary presenting symptom, followed by anemia and neurologic symptoms (frequent convulsions and unstable walking, respectively). Screening of amino acids and acyl carnitine in serum showed that the propionyl carnitine:acetylcarnitine ratio increased. Profiling of urinary organic acids by gas chromatography-mass spectrometry revealed high levels of methylmalonic acid. Homocysteine content in blood was increased. Comprehensive genetic analyses of peripheral blood-derived DNA demonstrated heterozygous variants of methylmalonic aciduria type C and homocystinuria (MMACHC) and amnionless (AMN) genes in our two patients, respectively. After active treatment, the clinical manifestations in Case 1 were relieved and urinary protein ceased to be observed; Case 2 had persistent proteinuria and was lost to follow-up. CONCLUSIONS: Analyses of the organic acids in blood and urine suggested MMA combined with homocysteinemia. In such diseases, reports of renal damage are uncommon and proteinuria as the initial presentation is rare. Molecular analysis indicated two different genetic causes. Although the pathologic mechanisms were related to vitamin B12, the severity and prognosis of renal lesions were different. Therefore, gene detection provides new insights into inherited metabolic diseases.
Asunto(s)
Errores Innatos del Metabolismo de los Aminoácidos/complicaciones , Hiperhomocisteinemia/complicaciones , Proteinuria/diagnóstico , Adolescente , Errores Innatos del Metabolismo de los Aminoácidos/genética , Aminoácidos/sangre , Secuencia de Bases , Carnitina/análogos & derivados , Carnitina/sangre , Preescolar , ADN/sangre , ADN/genética , Cromatografía de Gases y Espectrometría de Masas , Homocisteína/sangre , Humanos , Hiperhomocisteinemia/genética , Masculino , Ácido Metilmalónico/orina , Proteinuria/etiologíaRESUMEN
BACKGROUND: The long-term prognosis of Henoch-Schönlein purpura (HSP) depends on the severity of renal involvement, and crescent formation is considered an important risk factor for poor prognosis of Henoch-Schönlein purpura nephritis (HSPN). The objective of this study was to evaluate factors affecting crescent formation in children with HSPN. METHODS: Demographic factors, clinical characteristics, and laboratory data of children with HSPN with or without crescents were retrospectively analyzed. Univariate and multivariate logistic regression analyses were used to determine the risk factors of crescent formation in HSPN. RESULTS: A total of 191 children with HSPN were enrolled in the study. There were 107 (56%) males and 84 (44%) females, with a median age of 7 years (range: 2 years-15 years). International Study of Kidney Disease in Children (ISKDC) grading was used to divide subjects into two groups: those without glomerular crescent formation (ISKDC grades I-II, n = 146 cases) and those with glomerular crescent formation (ISKDC grades III-V, n = 45 cases). Logistic regression analysis showed that higher urinary white blood cell (WBC) count (OR = 3.300; 95% CI, 1.119-9.739; P = 0.0306) and higher urinary microalbumin/creatinine ratio (ACR) (OR = 25.053; 95% CI, 1.354-463.708; P = 0.0305) were independent risk factors for the formation of crescents in HSPN. The area under the receiver operating characteristic curve of urinary WBC and ACR were 0.753 and 0.698 respectively, with the Hosmer and Lemeshow goodness-of-fit test (P = 0.0669, P > 0.05). CONCLUSION: These results suggest that higher urinary WBC count and ACR should be strictly monitored for children with HSPN. Adequate clinical intervention for these risk factors may limit or prevent renal crescent formation.
Asunto(s)
Glomerulonefritis , Vasculitis por IgA , Nefritis , Niño , Preescolar , Femenino , Humanos , Vasculitis por IgA/complicaciones , Riñón , Masculino , Nefritis/etiología , Estudios Retrospectivos , Factores de RiesgoRESUMEN
BACKGROUND: X-linked lymphoproliferative disease (XLP) is a rare inherited X-linked primary immunodeficiency diseases (PID). One such disease, X-linked inhibitor of apoptosis protein (XIAP) deficiency, is characterized by Epstein-Barr virus-related hemophagocytic lymphohistiocytosis (EBV-HLH). However, EBV-HLH with coronary artery dilation and acute renal injury (AKI) in children is unusual. CASE PRESENTATION: We report the case of a young boy aged 17 months with a novel XIAP variant. He was initially diagnosed with EBV-HLH based on the HLH-2004 diagnostic criteria and the condition was accompanied by coronary artery dilation and acute renal injury. The comprehensive genetic analysis of peripheral blood-derived DNA revealed a hemizygous variant of the XIAP gene [c.116G > C(p.G39A)], which was inherited from his mother (heterozygous condition). After combined treatment with rituximab, intravenous immunoglobulin, corticosteroids, antiviral drugs, and mycophenolate mofetil (MMF) in addition to supportive therapy, his clinical manifestations and laboratory indexes were improved. The patient achieved complete remission with MMF treatment in the 8-month follow-up. CONCLUSIONS: We report the [c.116G > C(p.G39A)] variant in the XIAP gene for the first time in a case of XLP-2 associated with EBV-HLH. For male patients with severe EBV-HLH, the possibility of XLP should be considered and molecular genetic testing should be used early in auxiliary diagnosis. Reports of EBV-HLH with coronary artery dilation and AKI in children are rare. In the patients with EBV-HLH, color Doppler echocardiography and urine tests should be monitored regularly. If necessary, renal biopsy can be performed to clarify the pathology. Treatment with rituximab, immunosuppressors and supportive therapy achieved a good effect, but long-term follow-up is required.
Asunto(s)
Lesión Renal Aguda , Infecciones por Virus de Epstein-Barr , Linfohistiocitosis Hemofagocítica , Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/etiología , Niño , Vasos Coronarios , Dilatación , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/diagnóstico , Herpesvirus Humano 4/genética , Humanos , Lactante , Linfohistiocitosis Hemofagocítica/complicaciones , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/genética , Masculino , Proteína Inhibidora de la Apoptosis Ligada a X/genéticaRESUMEN
The Skp1-Cul1-F-box-protein (SCF) ubiquitin ligases are important parts of the ubiquitin system controlling many cellular biological processes in eukaryotes. However, the roles of SCF ubiquitin ligases remain unclear in phytopathogenic Magnaporthe oryzae. Here, we cloned 24 F-box proteins and confirmed that 17 proteins could interact with MoSkp1, showing their potential to participate in SCF complexes. To determine their functions, null mutants of 21 F-box-containing genes were created. Among them, the F-box proteins MoFwd1, MoCdc4 and MoFbx15 were found to be required for growth, development and full virulence. Fluorescent-microscopy observations demonstrated that both MoFbx15 and MoCdc4 were localized to the nucleus, compared with MoFwd1, which was distributed in the cytosol. MoCdc4 and MoFwd1 bound to MoSkp1 via the F-box domain, the deletion of which abrogated their function. Race tube and qRT-PCR assays confirmed that MoFwd1 was involved in circadian rhythm by regulating transcription and protein stability of the core circadian clock regulator MoFRQ. Moreover, MoFWD1 also orchestrates conidial germination by influencing conidial amino acids pools and oxidative stress release. Overall, our results indicate that SCF ubiquitin ligases play indispensable roles in development and pathogenicity in M. oryzae.
Asunto(s)
Proteínas F-Box/metabolismo , Proteínas Fúngicas/metabolismo , Magnaporthe/metabolismo , Magnaporthe/patogenicidad , Oryza/microbiología , Proteínas Cullin/metabolismo , Proteínas F-Box/genética , Proteínas Fúngicas/genética , Regulación Fúngica de la Expresión Génica , Magnaporthe/genética , Esporas Fúngicas/metabolismo , VirulenciaRESUMEN
Pyricularia oryzae is the causal pathogen of rice blast disease. Autophagy has been shown to play important roles in P. oryzae development and plant infection. The P. oryzae endosomal system is highly dynamic and has been shown to be associated with conidiogenesis and pathogenicity as well. To date, the crosstalk between autophagy and endocytosis has not been explored in P. oryzae. Here, we identified three P. oryzae VPS9 domain-containing proteins, PoVps9, PoMuk1 and PoVrl1. We found that PoVps9 and PoMuk1 are localized to vesicles and are each co-localized with PoVps21, a recognized marker of early endosomes. Deletion of PoVPS9 resulted in severe defects in endocytosis and autophagosome degradation and impaired the localization of PoVps21 to endosomes. Additionally, deletion of the PoMUK1 gene in the ΔPovps9 mutant background exhibited more severe defects in development, autophagy and endocytosis compared with the ΔPovps9 mutant. Pull-down assay showed that PoVps9 interacts with PoVps21, PoRab11 and PoRab1, which have been verified to participate in endocytosis. Furthermore, yeast two-hybrid and co-immunoprecipitation assays confirmed that PoVps9 directly interacts with the GDP form of PoVps21. Thus, PoVps9 is a key protein involved in autophagy and in endocytosis.
Asunto(s)
Autofagia/genética , Endocitosis/genética , Proteínas Fúngicas/genética , Magnaporthe/genética , Magnaporthe/patogenicidad , Oryza/microbiología , Endocitosis/fisiología , Endosomas/genética , Endosomas/metabolismo , Enfermedades de las Plantas/microbiología , Dominios Proteicos/genéticaRESUMEN
Polo-like kinase 1 (PLK1) is highly expressed in many cancers and therefore a biomarker of transformation and potential target for the development of cancer-specific small molecule drugs. RO3280 was recently identified as a novel PLK1 inhibitor; however its therapeutic effects in leukemia treatment are still unknown. We found that the PLK1 protein was highly expressed in leukemia cell lines as well as 73.3% (11/15) of pediatric acute myeloid leukemia (AML) samples. PLK1 mRNA expression was significantly higher in AML samples compared with control samples (82.95 ± 110.28 vs. 6.36 ± 6.35; p < 0.001). Kaplan-Meier survival analysis revealed that shorter survival time correlated with high tumor PLK1 expression (p = 0.002). The 50% inhibitory concentration (IC50) of RO3280 for acute leukemia cells was between 74 and 797 nM. The IC50 of RO3280 in primary acute lymphocytic leukemia (ALL) and AML cells was between 35.49 and 110.76 nM and 52.80 and 147.50 nM, respectively. RO3280 induced apoptosis and cell cycle disorder in leukemia cells. RO3280 treatment regulated several apoptosis-associated genes. The regulation of DCC, CDKN1A, BTK, and SOCS2 was verified by western blot. These results provide insights into the potential use of RO3280 for AML therapy; however, the underlying mechanisms remain to be determined.
Asunto(s)
Apoptosis/efectos de los fármacos , Azepinas/toxicidad , Proteínas de Ciclo Celular/antagonistas & inhibidores , Leucemia Mieloide Aguda/patología , Inhibidores de Proteínas Quinasas/toxicidad , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Pirimidinas/toxicidad , Azepinas/química , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/metabolismo , Niño , Preescolar , Análisis por Conglomerados , Fragmentación del ADN/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Femenino , Células HL-60 , Humanos , Células K562 , Estimación de Kaplan-Meier , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidad , Masculino , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Pirimidinas/química , Células Tumorales Cultivadas , Regulación hacia Arriba/efectos de los fármacos , Quinasa Tipo Polo 1RESUMEN
Rice blast is a devastating disease worldwide, threatening rice production and food security. The blast fungus Magnaporthe oryzae invades the host via the appressorium, a specialized pressure-generating structure that generates enormous turgor pressure to penetrate the host cuticle. However, owing to ongoing evolution of fungicide resistance, it is vitally important to identify new targets and fungicides. Here, we show that Trs85, a subunit of the transport protein particle III complex, is essential for appressorium-mediated infection in M. oryzae. We explain how Trs85 regulates autophagy through Ypt1 (a small guanosine triphosphatase protein) in M. oryzae. We then identify a key conserved amphipathic α helix within Trs85 that is associated with pathogenicity of M. oryzae. Through computer-aided screening, we identify a lead compound, SP-141, that affects autophagy and the Trs85-Ypt1 interaction. SP-141 demonstrates a substantial capacity to effectively inhibit infection caused by the rice blast fungus while also exhibiting wide-ranging potential as an antifungal agent with broad-spectrum activity. Taken together, our data show that Trs85 is a potential new target and that SP-141 has potential for the control of rice blast. Our findings thus provide a novel strategy that may help in the fight against rice blast.
Asunto(s)
Antifúngicos , Ascomicetos , Indoles , Magnaporthe , Piridinas , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Antifúngicos/metabolismo , Magnaporthe/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismoRESUMEN
Recalcitrant rice blast disease is caused by Magnaporthe oryzae, which has a significant negative economic reverberation on crop productivity. In order to induce the disease onto the host, M. oryzae positively generates many types of small secreted proteins, here named as effectors, to manipulate the host cell for the purpose of stimulating pathogenic infection. In M. oryzae, by engaging with specific receptors on the cell surface, effectors activate signaling channels which control an array of cellular activities, such as proliferation, differentiation and apoptosis. The most recent research on effector identification, classification, function, secretion, and control mechanism has been compiled in this review. In addition, the article also discusses directions and challenges for future research into an effector in M. oryzae.
Asunto(s)
Ascomicetos , Magnaporthe , Oryza , Magnaporthe/metabolismo , Oryza/metabolismo , Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismoRESUMEN
Mitophagy, as one of the most important cellular processes to ensure quality control of mitochondria, aims at transporting damaged, aging, dysfunctional or excess mitochondria to vacuoles (plants and fungi) or lysosomes (mammals) for degradation and recycling. The normal functioning of mitophagy is critical for cellular homeostasis from yeasts to humans. Although the role of mitophagy has been well studied in mammalian cells and in certain model organisms, especially the budding yeast Saccharomyces cerevisiae, our understanding of its significance in other fungi, particularly in pathogenic filamentous fungi, is still at the preliminary stage. Recent studies have shown that mitophagy plays a vital role in spore production, vegetative growth and virulence of pathogenic fungi, which are very different from its roles in mammal and yeast. In this review, we summarize the functions of mitophagy for mitochondrial quality and quantity control, fungal growth and pathogenesis that have been reported in the field of molecular biology over the past two decades. These findings may help researchers and readers to better understand the multiple functions of mitophagy and provide new perspectives for the study of mitophagy in fungal pathogenesis.Abbreviations: AIM/LIR: Atg8-family interacting motif/LC3-interacting region; BAR: Bin-Amphiphysin-Rvs; BNIP3: BCL2 interacting protein 3; CK2: casein kinase 2; Cvt: cytoplasm-to-vacuole targeting; ER: endoplasmic reticulum; IMM: inner mitochondrial membrane; mETC: mitochondrial electron transport chain; OMM: outer mitochondrial membrane; OPTN: optineurin; PAS: phagophore assembly site; PD: Parkinson disease; PE: phosphatidylethanolamine; PHB2: prohibitin 2; PX: Phox homology; ROS, reactive oxygen species; TM: transmembrane.