Search

Fusarium verticillioides, a well-known fungal pathogen that causes severe disease in maize and contaminates the grains with fumonisin B1 (FB1) mycotoxin, affects the yield and quality of maize worldwide. The intrinsic roles of peroxisome targeting signal (PTS)-containing proteins in phytopathogens remain elusive. We therefore explored the regulatory role and other biological functions of the components of PTS2 receptor complex, FvPex7 and FvPex20, in F. verticillioides. We found that FvPex7 directly interacts with the carboxyl terminus of FvPex20 in F. verticillioides. PTS2-containing proteins are recognized and bound by the FvPex7 receptor or the FvPex7-Pex20 receptor complex in the cytoplasm, but the peroxisome localization of the PTS2-Pex7-Pex20 complex is only determined by Pex20 in F. verticillioides. However, we observed that some putative PTS2 proteins that interact with Pex7 are not transported into the peroxisomes, but a PTS1 protein that interacts with Pex5 was detected in the peroxisomes. Furthermore, ΔFvpex7pex20 as well as ΔFvpex7pex5 double mutants exhibited reduced pathogenicity and FB1 biosynthesis, along with defects in conidiation. The PTS2 receptor complex mutants (ΔFvpex7pex20) grew slowly on minimal media and showed reduced sensitivity to cell wall and cell membrane stress-inducing agents compared to the wild type. Taken together, we conclude that the PTS2 receptor complex mediates peroxisome matrix proteins import and contributes to pathogenicity and FB1 biosynthesis in F. verticillioides. KEY POINTS: • FvPex7 directly interacts with FvPex20 in F. verticillioides. • vThe PTS2 receptor complex is essential for the importation of PTS2-containing matrix protein into peroxisomes in F. verticillioides. • Fvpex7/pex20 is involved in pathogenicity and FB1 biosynthesis in F. verticillioides.

Studies on the nutritional status of adolescents in Dankande community of Kaduna metropolis were carried out. Adolescence is a period between 10 to 19 years of age. This period is a critical period where a healthy diet is needed for proper growth, development, academic performances and human capital development. A validated semi-structured questionnaire was used to assessed socio-demographic characteristic of the adolescent caregivers and dietary pattern of the adolescent while weight, height and BMI were used to assess the anthropometry indices of adolescent. 37.2% of adolescents were between age 10-14 years while 62.8% were between 15-19 years. Also, 5.1% of the adolescents were married, 88.5 were single and 6.4% windowed. (19.2%) of adolescents has no formal education, (2.6%) completed primary school, (29.5%) uncompleted primary school, (2.6%) completed Junior Secondary School, (19.2%) uncompleted Junior Secondary School, while (1.3%) completed Senior Secondary and (25.6%) did not complete Senior Secondary respectively. However, on average (35.9%) of adolescent were dieting and (64.1%) were not dieting while (32.1%) were concerned about their weight and (67.9%) were not concerned about their weight. Few adolescents were losing control of their weight (24.4%) while the majority had their weight in check (75.6%), they engaged in physical activity (85.9%), while many adolescents spent more than two hours per day watching tv/games (69.2%). 17.9% engage in smoking while (5.1%) are involved in drinking alcohol, beer or wine. The nutritional status of adolescents of Dankande community of Kaduna state (56.4%) is good when compared with the national average

Isw2 is known to bind DNA, using a Myb-type DNA binding domain and with another part of the protein interact with histones in the closest nucleosome to pull the two closest nucleosomes closer to the binding site using ATP. These bindings hinder these nucleosomes’ sliding movements and affect histone tail modification and DNA methylation but give more space for sliding and access for transcription factors further away from the Isw2 DNA binding sites. In a previous paper, we have knocked out the Magnaporthe oryzae Isw2 protein and complemented it with a GFP-labelled construct. We found that the MoISW2 is needed, especially in the later necrotrophic stages of infection when the plant starts defending itself.Using published transcriptomic data, we have now found that MoISW2 is mainly co-regulated with Histone 4 (MoHIS4), which likely indicates that MoIsw2 predominately interacts with MoHis4. We performed a ChIP-seq experiment using MoIsw2-GFP to map the binding sites and investigated if MoIsw2 regulates genes by the limited sliding type mechanism and if this regulation could be involved in pathogenicity regulation. Common motifs were found in the binding DNA sequences using MEME. Interestingly, these motifs were mainly intergenic, and a dominant palindrome motif was present in 200 sequences.We further performed an RNAseq for ΔMoisw2 compared with the Ku80 background strain and used genes sorted in physical order on the supercontigs to determine the effect of the mutation on the regulation of the genes physically close to the MoIsw2 binding sites. The genes close to the binding site were more absolutely regulated in the ΔMoisw2 mutant as expected due to the limited sliding mechaninsm. As nucleosomes are evenly distributed at roughly 200bp distance, there should be an interference pattern of regulation of genes centered around the MoIsw2 DNA binding site if the genes are roughly evenly distributed now given more space to slide due to this mechnism, which could be confirmed. We queried the NCBI database again and checked where the about 200 palindromic sequences were found in the genome to investigate if MoIsw2 binds to any known structures in the DNA. The palindromic sequences were found in conserved retrotransposon elements that generally contain palindromes. Since these retrotransposon elements can move place, they can create new regulatory variations with MoIsw2. Many avirulence genes recognized by different host plant cultivars and typically vary in expression between pathogen isolates were close to the MoIsw2 DNA binding site. That could mean that mobile elements associated with some MoIsw2 DNA binding sites are involved in creating variations in the pathogenicity of different M. oryzae strains. To test this idea, we searched through the transcriptomic data of our strain (70-15) and another strain (98-05) for variation in AVR expression during infection and if differences in MoIsw2 binding could be the cause for this variation and it seems to be that. Finally, we found that most of the genes upregulated in the ΔMoisw2 mutant regulate biomass growth (DNA-binding and quality control, and TFs overrepresented). In contrast, the ones downregulated have to do with mainly mitochondrial oxidative phosphorylation, oxidative stresses, and secondary metabolites.Similar results for enriched and depleted genes were found for all genes in our ChIP-seq data for genes closest to MoIsw2 binding. We conclude that MoIsw2 interaction with nucleosomes and binding to palindromic DNA in transposons located between genes creates a possibility for an evolutionary fast variation of offspring regulatory pattern without loss of genes through mutation and fast creation of M.oryzae strains with new cultivar host ranges in response to defenses by resistant cultivars and consequently a fast break of resistance. MoISW2 seems to lay a mechanistic ground for natural adaptation-directed fast evolution (NADFE) of M. oryzae, which is discussed as a new concept for Eukaryotes.

Secretion is a fundamental process in all living organisms. Using conventional secretion pathways, many plant pathogens release effectors into the host plants to downregulate immunity and promote infection. However, this does not always constitute the only way that effectors are sorted and tracked to their final destination such as the biotrophic interfacial complex-associated effectors produced by the blast fungus Magnaporthe oryzae. Here, we uncover a novel unconventional route originating from fungal vacuolar membrane to the host interface and plasma membrane. We found that a GFP-MoRab7 labeled vacuole is closely associated with the interface structure throughout M. oryzae invasive growth. Conditional inactivation of MoRab7 impaired the establishment of the biotrophy interface and secretion of Pwl2 effector. To perform the vacuolar trafficking pathway, MoRab7 first recruits the retromer complex to the vacuole membrane, enabling it recognizes a batch of SNARE proteins, including the v-SNARE MoSnc1. Live-cell imaging supports both retromer complex component and MoSnc1 protein labeled vesicles showing the trafficking dynamics toward the interface or plasma membrane, and then fusion with target membranes. Lastly, disruption of the MoRab7/Retromer/MoSnc1-based endolysosomal cascade affects effector secretion and fungal pathogenicity. Taken together, we discovered an unconventional protein and membrane trafficking route starting from the fungal endolysosomes to the M. oryzae-rice interaction interface, and dissect the role of MoRab7/Retromer/MoSnc1 constituent sorting machinery in effector secretion during invasive growth in M. oryzae.

Calcium and manganese transporters play important roles in regulating Ca

In eukaryotic cells, Rab GTPases and the retromer complex are important regulators of intracellular protein transport. However, the mechanistic relationship between Rab GTPases and the retromer complex in relation to filamentous fungal development and pathogenesis is unknown. In this study, we used Magnaporthe oryzae, an important pathogen of rice and other cereals, as a model filamentous fungus to dissect this knowledge gap. Our data demonstrate that the core retromer subunit MoVps35 interacts with the Rab GTPase MoYpt7 and they colocalize to the endosome. Without MoYpt7, MoVps35 is mislocalized in the cytoplasm, indicating that MoYpt7 plays an important role in the recruitment of MoVps35. We further demonstrate that the expression of an inactive MoYpt7‐DN (GDP‐bound form) mutant in M. oryzae mimicks the phenotype defects of retromer cargo‐sorting complex (CSC) null mutants and blocks the proper localization of MoVps35. In addition, our data establish that MoVps17, a member of the sorting nexin family, is situated at the endosome independent of retromer CSC but regulates the sorting function of MoVps35 after its recruitment to the endosomal membrane by MoYpt7. Taken together, these results provide insight into the precise mechanism of retromer CSC recruitment to the endosome by MoYpt7 and subsequent sorting by MoVps17 for efficient conidiation and pathogenicity of M. oryzae., The retromer CSC subcomplex is recruited by MoYpt7 and sequentially sorted by MoVps17‐MoVps5 subcomplex for autophagy and endosome dynamics, which mediate the effective conidiation and pathogenicity of Magnaporthe oryzae.

The membrane trafficking system is important for compartmentalization of the biosynthesis pathway and secretion of deoxynivalenol (DON) mycotoxin (a virulence factor) in Fusarium graminearum. Flippases are transmembrane lipid transporters and mediate a number of essential physiological steps of membrane trafficking, including vesicle budding, charging, and protein diffusion within the membrane. However, the roles of flippases in secondary metabolism remain unknown in filamentous fungi. Herein, we identified five flippases (FgDnfA, FgDnfB, FgDnfC1, FgDnfC2, and FgDnfD) in F. graminearum and established their specific and redundant functions in the development and pathogenicity of this phytopathogenic fungus. Our results demonstrate that FgDnfA is critical for normal vegetative growth while the other flippases are dispensable. FgDnfA and FgDnfD were found crucial for the fungal pathogenesis, and a remarkable reduction in DON production was observed in ΔFgDNFA and ΔFgDNFD. Deletion of the FgDNFB gene increased DON production to about 30 times that produced by the wild type. Further analysis showed that FgDnfA and FgDnfD have positive roles in the regulation of trichothecene (TRI) genes (TRI1, TRI4, TRI5, TRI6, TRI12, and TRI101) expression and toxisome reorganization, while FgDnfB acts as a negative regulator of DON synthesis. In addition, FgDnfB and FgDnfD have redundant functions in the regulation of phosphatidylcholine transport, and double deletion of FgDNFB and FgDNFD showed serious defects in fungal development, DON synthesis, and virulence. Collectively, our findings reveal the distinct and specific functions of flippase family members in F. graminearum and principally demonstrate that FgDnfA, FgDnfD, and FgDnfB have specific spatiotemporal roles during toxisome biogenesis., In Fusarium graminearum, FgDnfA and FgDnfD positively regulate deoxynivalenol (DON) production, trichothecene gene expressions, and toxisome reorganization, while FgDnfB is a negative regulator of DON synthesis.

Rab GTPases are key regulators of membrane and intracellular vesicle transports. However, the biological functions of FgRab1 are still unclear in the devastating wheat pathogen Fusarium graminearum. In this study, we generated constitutively active (CA) and dominant-negative (DN) forms of FgRAB1 from the wild-type PH-1 background for functional analyses. Phenotypic analyses of these mutants showed that FgRab1 is important for vegetative growth, cell wall integrity and hyphal branching. Compared to the PH-1 strain, the number of spores produced by the Fgrab1DN strain was significantly reduced, with obviously abnormal conidial morphology. The number of septa in the conidia of the Fgrab1DN mutant was fewer than that observed in the PH-1 conidia. Fgrab1DN was dramatically reduced in its ability to cause Fusarium head blight symptoms on wheat heads. GFP-FgRab1 was observed to partly localize to the Golgi apparatus, endoplasmic reticulum and Spitzenkörper. Furthermore, we found that FgRab1 inactivation blocks not only the transport of the v-SNARE protein FgSnc1 from the Golgi to the plasma membrane but also the fusion of endocytic vesicles with their target membranes and general autophagy. In summary, our results indicate that FgRab1 plays vital roles in vegetative growth, conidiogenesis, pathogenicity, autophagy, vesicle fusion and trafficking in F. graminearum.

Cytokine storm is a phrase used to refer to an abrupt upsurge in the circulating levels of various pro-inflammatory cytokines, causing increased stimulation and activity of immune cells during disease conditions. The binding of pattern recognition receptors to pathogen-associated molecular patterns during COVID-19 infection recruits response machinery involving the activation of transcription factors and proteins required for a robust immune response by host cells. These immune responses could be influenced by epigenetic modifications as evidenced by significant variations in COVID-19 pathophysiology and response to therapy observed among patients across the globe. Considering that circulating levels of interleukin 1, tumor necrosis factor-α, and interleukin 6 are significantly elevated during cytokine storm in COVID-19 patients, genetic and epigenetic variations in the expression and function of these proteins could enhance our understanding of the disease pathogenesis. Treatment options that repress the transcription of specific cytokine genes during COVID-19 infection could serve as possible targets to counteract cytokine storm in COVID-19. Therefore, the present article reviews the roles of cytokines and associated genes in the COVID-19 cytokine storm, identifies epigenetic modifications associated with the disease progression, and possible ameliorative effects of some vitamins and minerals obtained as epigenetic modifiers for the control of cytokine storm and disease severity in COVID-19 patients. PRACTICAL APPLICATIONS: COVID-19 causes mortality and morbidity that adversely affect global economies. Despite a global vaccination campaign, side effects associated with vaccination, misconceptions, and a number of other factors have affected the expected successes. Cytokine storm in COVID-19 patients contributes to the disease pathogenesis and response to therapy. Epigenetic variations in the expression of various cytokines could be implicated in the different outcomes observed in COVID-19 patients. Certain vitamins and minerals have been shown to interfere with the expression and activity of cytokines implicated in cytokine storm, thereby counteracting observed pathologies. This review examines cytokines implicated in cytokine storm in COVID-19, epigenetic modifications that contribute to increased expression of identified cytokines, specific foods rich in the identified vitamins and minerals, and suggests their possible ameliorative benefits. The article will be beneficial to both scientists and the general public who are interested in the role of vitamins and minerals in ameliorating COVID-19.

Rab GTPases are key regulators of membrane and intracellular vesicle transports. However, the biological functions of FgRab1 are still unclear in the devastating wheat pathogen Fusarium graminearum. In this study, we generated constitutively active (CA) and dominant-negative (DN) forms of FgRAB1 from the wild-type PH-1 background for functional analyses. Phenotypic analyses of these mutants showed that FgRab1 is important for vegetative growth, cell wall integrity and hyphal branching. Compared to the PH-1 strain, the number of spores produced by the Fgrab1DN strain was significantly reduced, with obviously abnormal conidial morphology. The number of septa in the conidia of the Fgrab1DN mutant was fewer than that observed in the PH-1 conidia. Fgrab1DN was dramatically reduced in its ability to cause Fusarium head blight symptoms on wheat heads. GFP-FgRab1 was observed to partly localize to the Golgi apparatus, endoplasmic reticulum and Spitzenkörper. Furthermore, we found that FgRab1 inactivation blocks not only the transport of the v-SNARE protein FgSnc1 from the Golgi to the plasma membrane but also the fusion of endocytic vesicles with their target membranes and general autophagy. In summary, our results indicate that FgRab1 plays vital roles in vegetative growth, conidiogenesis, pathogenicity, autophagy, vesicle fusion and trafficking in F. graminearum.

The retromer complex, composed of the cargo-selective complex (CSC) Vps35-Vps29-Vps26 in complex with the sorting nexin dimer Vps5-Vps17, mediates the sorting and retrograde transport of cargo proteins from the endosomes to the trans-Golgi network in eukaryotic cells. Rab proteins belong to the Ras superfamily of small GTPases and regulate many trafficking events including vesicle formation, budding, transport, tethering, docking and fusion with target membranes. Herein, we investigated the potential functional relationship between the retromer complex and the 11 Rab proteins that exist in Fusarium graminearum using genetic and high-resolution laser confocal microscopic approaches. We found that only FgRab5 (FgRab5A and FgRab5B) and FgRab7 associate with the retromer complex. Both FgVps35-GFP and FgVps17-GFP are mis-localized and appear diffused in the cytoplasm of ΔFgrab5A, ΔFgrab5B and ΔFgrab7 mutants as compared to their punctate localization within the endosomes of the wild-type. FgRab7 and FgRab5B were found to co-localize with the retromer on endosomal membranes. Most strikingly, we found that these three Rab GTPases are indispensable for endosome biogenesis as both early and late endosomes could not be detected in the cells of the mutants after FM4-64 staining of the cells, while they were very clearly seen in the wild-type PH-1. Furthermore, FgRab7 was found to recruit FgVps35 but not FgVps17 to the endosomal membranes, whereas FgRab5B recruits both FgVps35 and FgVps17 to the membranes. Thus, we conclude that the Rab proteins FgRab5A, FgRab5B and FgRab7 play critical roles in the biogenesis of endosomes and in regulating retromer-mediated trafficking in F. graminearum.

Global food security is threatened by insect pests of economically important crops. Chemical pesticides have been used frequently for the last few decades to manage insect pests throughout the world. However, these chemicals are hazardous for human health as well as the ecosystem. In addition, several pests have evolved resistance to many chemicals. Finding environment friendly alternatives lead the researchers to introduce biocontrol agents such as entomopathogenic fungi (EPF). These fungi include various genera that can infect and kill insects efficiently. Moreover, EPFs have considerable host specificity with a mild effect on non-target organisms and can be produced in bulk quantity quickly. However, insights into the biology of EPF and mechanism of action are of prime significance for their efficient utilization as a biocontrol agent. This review focuses on EPF-mediated insect management by explaining particular EPF strains and their general mode of action. We have comprehensively discussed which criteria should be used for the selection of pertinent EPF, and which aspects can impact the EPF efficiency. Finally, we have outlined various advantages of EPF and their limitations. The article summarizes the prospects related to EPF utilization as biocontrol agents. We hope that future strategies for the management of insects will be safer for our planet.

In filamentous fungi, hyphal growth depends on the continuous delivery of vesicles to the growing tips. It is unclear how fast-growing hyphae coordinate simultaneous cell extension and expansion in the tip cells. We have functionally characterized 12 TBC (Tre-2/Bub2/Cdc16) domain-containing proteins in Fusarium graminearum. Among them, FgMsb3 is found to regulate hyphal tip expansion and to be required for pathogenicity. The regulatory mechanism of FgMsb3 has been further investigated by genetic, high-resolution microscopy and high-throughput co-immunoprecipitation strategies. The FgMsb3 protein localizes at the polarisome and the hyphal apical dome (HAD) where it acts as a GTPase-activating protein for FgRab8 which is required for apical secretion-mediated growth and pathogenicity. Deletion of FgMSB3 causes excessive polarized trafficking but blocks the fusion of FgSnc1-associated vesicles to the plasma membrane. Moreover, we establish that FgSpa2 interacts with FgMsb3, enabling FgMsb3 tethering to the polarisome. Loss of FgSpa2 or other polarisome components (FgBud6 and FgPea2) causes complete shifting of FgMsb3 to the HAD and this affects the polarized growth and pathogenicity of the fungus. In summary, we conclude that FgSpa2 regulates FgMsb3-FgRab8 cascade and this is crucial for creating a steady-state equilibrium that maintains continuous polarized growth and contributes to the pathogenicity of F. graminearum.

Endosomal sorting machineries regulate the transport of their cargoes among intracellular compartments. However, the molecular nature of such intracellular trafficking processes in pathogenic fungal development and pathogenicity remains unclear. Here, we dissect the roles and molecular mechanisms of two sorting nexin proteins and their cargoes in endosomal recycling in Fusarium graminearum using high-resolution microscopy and high-throughput co-immunoprecipitation strategies. We show that the sorting nexins, FgSnx41 and FgSnx4, interact with each other and assemble into a functionally interdependent heterodimer through their respective BAR domains. Further analyses demonstrate that the dimer localizes to the early endosomal membrane and coordinates endosomal sorting. The small GTPase FgRab5 regulates the correct localization of FgSnx41-FgSnx4 and is consequently required for its trafficking function. The protein FgSnc1 is a cargo of FgSnx41-FgSnx4 and regulates the fusion of secreted vesicles with the fungal growing apex and plasma membrane. In the absence of FgSnx41 or FgSnx4, FgSnc1 is mis-sorted and degraded in the vacuole, and null deletion of either component causes defects in the fungal polarized growth and virulence. Overall, for the first time, our results reveal the mechanism of FgSnc1 endosomal recycling by FgSnx41-FgSnx4 heterodimer which is essential for polarized growth and pathogenicity in F. graminearum.

The mangrove Kandelia candel (L.) Druce experiences daily flooding cycles. To explore the molecular mechanism underlying the physiological adaptation of K. candel to flooding, the potential role of protein phosphorylation in flooding responses was investigated by a large-scale quantitative phosphoproteomic analysis using isobaric tag for relative and absolute quantitation. Total 2141 unique phosphopeptides and 2603 non-redundant phosphorylation sites were identified from 1516 phosphoproteins in K. candel leaves. In addition to known phosphorylation motifs, three new motifs [GSP], [GxxSP] and [RSxS] were discovered. The phosphorylation levels of 96 differentially expressed phosphoproteins, including those involved in pyruvate metabolism and energy production, were identified in response to flooding. The physiological parameters and transcriptional levels relevant to flooding responses including photosynthesis, pyruvate metabolism, and ROS production were investigated and all were found to be robust under flooding conditions. The consistent results of the phosphoproteomic, physiological analyses and transcriptional levels reinforce each other to demonstrate that K. candel adapts to flooding through maintaining sufficient photosynthesis activities, achieving effective anaerobic respiration and increasing pentose phosphate pathway flux. Protein phosphorylation is likely to play a major role in the regulation of these pathways which together contribute to stable energy supply that enhances flooding tolerance in K. candel. Biological significance Flooding stress is one of the major environmental stresses. The woody mangrove Kandelia candel experiences daily flooding cycles in its natural habitat. Protein phosphorylation is a crucial regulatory mechanism in plants' responses to both biotic and abiotic stresses. To analyze phosphorylation levels in critical enzymes involved in key metabolic pathways, we employed phosphoproteomic approach to dissect the adaptive mechanism of K. candel to flooding conditions. To our knowledge, this is the first large-scale quantitative phosphoproteomic analyses of K. candel's flooding responses. Multiplex iTRAQ-based quantitative proteomic and Nano-LC–MS/MS methods were used to construct the phosphorproteome. Our results indicate that K. candel is able to acquire stable energy supply under flooding by maintaining sufficient photosynthesis activities, enhancing effective anaerobic respiration and increasing pentose phosphate pathway (PPP) flux. The protein phosphorylation found in photosynthesis, anaerobic respiration and PPP is likely to play important roles in the flooding tolerance of K. candel.

Vps17 is a sorting nexin (SNX) and a component of the retromer, a protein complex mediating retrograde vesicle transport between endosomes and the trans-Golgi network. However, its role in the development and pathogenicity of filamentous fungi such as the rice blast fungus (Magnaporthe oryzae) remains unclear. We investigate the functional relationship between the SNX and the cargo-selective complex (CSC) of the fungal retromer by genetic analysis, live cell imaging and immunological assay. Our data show that the MoVps17 null mutation causes defects in growth, development and pathogenicity in M. oryzae. MoVps17 is localized to endosomes depending on the activity of phosphatidylinositol 3-kinase (PI3K), a key enzyme for fungal development and infection. Both PX and BAR domains of MoVps17 are essential for its endosomal localization and function. Furthermore, our yeast two-hybrid assays show that MoVps17 and MoVps5 can interact. Lastly, live cell imaging suggests that MoVps17 can regulate early endosome fusion and budding as well as endocytosis. Taken together, our results suggest that MoVps17 specifically functions as a retromer component with CSC and also plays a distinct role in the regulation of endosome dynamics during fungal development and plant infection.

SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) facilitate intracellular vesicle trafficking and membrane fusion in eukaryotic cells, and play a vital role in growth, development and pathogenicity of phytopathogens. Fusarium head blight (FHB) caused by F. graminearum is one of the most devastating diseases of wheat and barley worldwide. Sec22 is a member of the SNARE family of proteins and its homologues have been shown to have diverse biological roles in different organisms. However, the functions of this protein in the development and pathogenesis of F. graminearum are currently unknown. In this study, we employed integrated biochemical, microbiological and molecular genetic approaches to investigate the roles of FgSec22 in F. graminearum. Our data reveal that this SNARE protein is localized to endoplasmic reticulum (ER) and is indispensable for normal conidiation, conidial morphology and pathogenesis of this phytopathogenic fungus. Our biochemical assay of deoxynivalenol (DON) reveals the active involvement of this protein in the production of this mycotoxin in F. graminearum. This has further been confirmed by qRT-PCR analyses of trichothecene (TRI) genes' expression where the ΔFgsec22 deletion mutant demonstrated a significant down-regulation of these genes in comparison to the wild-type PH-1. Unlike the wild-type and the complemented strain, the mutant strain presents a remarkable defect in colony formation which reflects the critical role it plays in vegetative growth. Collectively, our data support that the SNARE protein FgSec22 is required for vegetative growth, pathogenesis and DON biosynthesis in F. graminearum.

AP-2 complex is widely distributed in eukaryotes in the form of heterotetramer that functions in the uptake of membrane proteins during mammalian/plant clathrin-mediated endocytosis. However, its biological function remains mysterious in pathogenic fungi. In this study, the wheat scab fungus, Fusarium graminearum, was used to characterise the biological function of the AP-2 complex. Our study shows that FgAP-2 complex plays a critical role in the maintenance of hyphal polarity. Lack of any subunit (FgAP2α , FgAP2β , FgAP2σ , and FgAP2mu ) of the FgAP-2 complex significantly affects the fungal vegetative growth, conidial morphology, and germination. Remarkably, FgAP-2 complex is important for the fungal pathogenicity, especially during colonisation and extension after infecting the host. The FgAP-2 complex is expressed ubiquitously at all developmental stages but having more concentrated protein distribution at the subapical collar and septa in young growing hyphae. Although FgAP-2 complex displays similar dynamic behaviour to the actin patch components and accumulates at endocytic sites, it is dispensable for general endocytosis. We further demonstrated that FgAP-2 complex is required for polar localisation of the lipid flippases FgDnfA and FgDnfB, which led to the proposal that FgAP-2 functions as a cargo-specific adaptor that promotes polar growth and colonising ability of F. graminearum.

Retromer complexes mediate protein trafficking from the endosomes to the trans-Golgi network (TGN) or through direct recycling to the plasma membrane. In yeast, they consist of a conserved trimer of the cargo selective complex (CSC), Vps26–Vps35–Vps29 and a dimer of sorting nexins (SNXs), Vps5–Vps17. In mammals, the CSC interacts with different kinds of SNX proteins in addition to the mammalian homologues of Vps5 and Vps17, which further diversifies retromer functions. The retromer complex plays important roles in many cellular processes including restriction of invading pathogens. In this review, we summarize some recent developments in our understanding of the physiological and pathological functions of the retromer complex.

Vps17 is a sorting nexin (SNX) and a component of the retromer, a protein complex mediating retrograde vesicle transport between endosomes and the trans-Golgi network. However, its role in the development and pathogenicity of filamentous fungi such as the rice blast fungus (Magnaporthe oryzae) remains unclear. We investigate the functional relationship between the SNX and the cargo-selective complex (CSC) of the fungal retromer by genetic analysis, live cell imaging and immunological assay. Our data show that the MoVps17 null mutation causes defects in growth, development and pathogenicity in M. oryzae. MoVps17 is localized to endosomes depending on the activity of phosphatidylinositol 3-kinase (PI3K), a key enzyme for fungal development and infection. Both PX and BAR domains of MoVps17 are essential for its endosomal localization and function. Furthermore, our yeast two-hybrid assays show that MoVps17 and MoVps5 can interact. Lastly, live cell imaging suggests that MoVps17 can regulate early endosome fusion and budding as well as endocytosis. Taken together, our results suggest that MoVps17 specifically functions as a retromer component with CSC and also plays a distinct role in the regulation of endosome dynamics during fungal development and plant infection.

Plant anthocyanin biosynthesis is well understood, but the regulatory mechanism in purple foliage tea remains unclear. Using isobaric tag for relative and absolute quantification (iTRAQ), 815 differential proteins were identified in the leaves of Zijuan tea, among which 20 were associated with the regulation of anthocyanin metabolism. We found that the abundances of anthocyanin synthesis-related enzymes such as chalcone synthase, chalcone isomerase, dihydroflavonol 4-reductase and anthocyanin synthetase, as well as anthocyanin accumulation-related UDP-glucosyl transferase and ATP-binding cassette (ABC) transporters in the purple leaves were all significantly higher than those in the green leaves. The abundances of the transcription factors bHLH and HY5, regulating anthocyanin biosynthesis at transcriptional level were also obviously higher in purple leaves than those in green leaves. In addition, bifunctional 3-dehydroquinate dehydratase and chorismate mutase in purple leaves were distinctly higher in abundance compared to green leaves, which provided sufficient phenylalanine substrate for anthocyanin synthesis. Furthermore, lignin synthesis was found to be reduced due to the lower abundances of cinnamoyl-CoA reductase 1, peroxidase 15 and laccase-6, which resulted in increase of intermediates flow into anthocyanin synthesis pathway. The physiological data were consistent with proteomic results. These four aspects of biosynthetic regulation contribute to anthocyanin accumulation in purple leaves of Zijuan tea.

Context: Kano State Refuse Management and Sanitation board workers are constantly exposed to bioaerosol inhalation, including toxins and biotoxins that are been released from the waste. Aims: The aim of this study is to evaluate and determine the respiratory health status of Workers. Methodology: The study was a cross-sectional survey with 129 participants recruited using a convenience sampling technique. Forced vital capacity, forced expiratory volume in 1 s and St. George questionnaire were used to collect data and the result was analysed using descriptive statistics of frequencies, percentages and graphs, while the differences and relationships were obtained using one-way ANOVA and Spearman rank correlation co-efficient, respectively. Results: The mean age of the participants was 34.2 years. Up to 75.2% of the participants were male, whereas 24.8% were female. Up to 40% of participants did not have any respiratory symptoms, 35% had mild symptoms, 14% had moderate symptoms and 11% had severe respiratory symptoms. The symptoms include dyspnea, coughing, excessive mucus secretion and breathlessness. Respiratory symptoms was positively related to the length of exposure (P = 0.029). There was no significant difference in respiratory symptoms between waste collectors, sweepers and drivers. Furthermore, no relationship was found between the age of the workers and respiratory symptom (P = 0.056). Significant difference (P = 0.003) was observed between gender of the participants and respiratory health. Conclusions: Waste disposal work has significant impact on respiratory health. The provision of health education for safety and proper use of personal protection is necessary to reduce the impact of pollutant on respiratory health.

Background: Giant congenital melanocytic nevus is defined as a melanocytic lesion present at birth that reaches a diameter of more than 20 cm in adulthood. Its incidence is estimated as below 1:500,000 newborns. These lesions have a major psychosocial impact on the patient and the family because of its unsightly appearance in addition to neurological complications and high risk of malignant transformation into a melanoma. Case: A 6-month-old girl presented with hyperpigmented skin lesions over the back, gluteal regions, perineum, thighs, and scalp since birth with a progressive increase in number and sizes of satellite lesions all over the body. A clinical diagnosis of giant cell melanocytic nevi was made because of the sizes, location, and color of the lesions. Although she was planned to have a thorough neurological assessment due to the number and sizes of the lesions, she was lost to follow-up because of financial constraints and the perception that no medical/surgical intervention could be offered to her. Conclusions: Giant congenital melanocytic nevi are rarely seen or reported. It is however worthy to note that adequate investigation, proper and effective communications between physicians and the parents/patient, and monitoring for neurological complications are essential in ensuring satisfaction in the quality of life of these patients.

Carbon Catabolite Repression (CCR) has fascinated scientists and researchers around the globe for the past few decades. This important mechanism allows preferential utilization of an energy-efficient and readily available carbon source over relatively less easily accessible carbon sources. This mechanism helps microorganisms to obtain maximum amount of glucose in order to keep pace with their metabolism. Microorganisms assimilate glucose and highly favorable sugars before switching to less-favored sources of carbon such as organic acids and alcohols. In CCR of filamentous fungi, CreA acts as a transcription factor, which is regulated to some extent by ubiquitination. CreD-HulA ubiquitination ligase complex helps in CreA ubiquitination, while CreB-CreC deubiquitination (DUB) complex removes ubiquitin from CreA, which causes its activation. CCR of fungi also involves some very crucial elements such as Hexokinases, cAMP, Protein Kinase (PKA), Ras proteins, G protein-coupled receptor (GPCR), Adenylate cyclase, RcoA and SnfA. Thorough study of molecular mechanism of CCR is important for understanding growth, conidiation, virulence and survival of filamentous fungi. This review is a comprehensive revision of the regulation of CCR in filamentous fungi as well as an updated summary of key regulators, regulation of different CCR-dependent mechanisms and its impact on various physical characteristics of filamentous fungi.

Background: Neonatal mortality remains high and currently accounts for about 54 and 29% of infant and under-five mortality rates, respectively, in Nigeria. Newborn deaths usually result from varying causes, some of which are neonatal emergencies. The study was conducted to document neonatal emergencies and their relative contributions to newborn death. Patients: and Methods A retrospective review of emergency cases admitted into the Special Care Baby Unit (SCBU) of Ahmadu Bello University Teaching Hospital, Zaria in Northwestern Nigeria over an 18-month period (January 2013–June 2014) detailing information on age, sex, place of delivery, birth weight and outcome. Results: About 70% (700/997) of the admissions were the emergency cases of which severe neonatal jaundice, sepsis and perinatal asphyxia accounted for 96%. A mortality of 9.8% was recorded with the case fatality rates of 5, 11, 18.8 and 25% for severe neonatal jaundice, neonatal sepsis, perinatal asphyxia and neonatal tetanus, respectively. Overall, neonatal emergencies accounted for 68% of neonatal mortality in the SCBU. Outborns were 1.4 times more likely to die from these emergencies compared to inborns. Conclusion: Neonatal emergencies constitute a major proportion of admissions and deaths in Zaria. Efforts should be directed at the prevention of the three major emergencies (neonatal jaundice, sepsis, perinatal asphyxia) identified and provision of available, accessible and affordable neonatal healthcare services.