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Transcription factors (TFs) orchestrate the regulation of cellular gene expression and thereby determine cell functionality. In this study, we analyzed the distribution of TFs containing domains, which named as ZnFTFs, both in ascomycete and basidiomycete fungi. We found that ZnFTFs were widely distributed in these fungal species, but there was more expansion of the ZnFTF class in Ascomycota than Basidiomycota. We identified 40 ZnFTFs in Ustilaginoidea virens, and demonstrated the involvement of UvZnFTF1 in vegetative growth, conidiation, pigment biosynthesis and pathogenicity. RNA-Seq analysis suggested that UvZnFTF1 may regulate different nutrient metabolism pathways, the production of secondary metabolites, and the expression of pathogen-host interaction genes and secreted protein- encoding genes. Analysis of the distribution of different fungal TFs in U. virens further demonstrated that UvZnFTFs make up a large TF family and may play essential biological roles in U. virens.

In filamentous fungi, the conserved transcription factors play important roles in multiple cellular and developmental processes. The GATA proteins, a family of GATA-binding zinc finger transcription factors, play diverse functions in fungi. Ustilaginoidea virens is an economically important pathogen-causing rice false smut worldwide. To gain additional insight into the cellular and molecular mechanisms of this pathogen, in this study, we identified and functionally characterized seven GATA proteins from the U. virens genome (UvGATA). Sequences analysis indicated that these GATA proteins are divided into seven clades. The proteins in each clade contained conserved clade-specific sequences and structures, thus leading to the same motif serving different purposes in various contexts. The expression profiles of UvGATA genes at different infection stages and under [H.sub.2][O.sub.2] stress were detected. Results showed that the majority of UvGATA genes performed functions at both processes, thereby confirming the roles of these genes in pathogenicity and reactive oxygen species stress tolerance. This study provided an important starting point to further explore the biological functions of UvGATA genes and increased our understanding of their potential transcriptional regulatory mechanisms in U. virens. Key words: Ustilaginoidea virens, GATA domain, conversed domain, expression analysis. Resume : Chez les champignons filamenteux, les facteurs de transcription conserves jouent des roles importants dans de multiples processus cellulaires et developpementaux. Les proteines GATA, une famille de facteurs de transcription (a doigts de zinc) a motif de liaison GATA, jouent divers roles chez les champignons. L'Ustilaginoidea virens est un agent pathogene d'importance economique qui cause le faux charbon chez le riz. Pour mieux connaitre les mecanismes moleculaires et cellulaires de cet agent pathogene, les auteurs ont identifie et caracterise la fonction de sept proteines GATA au sein du genome de l'U. virens (UvGATA). L'analyse des sequences a revele que ces proteines appartiennent a sept clades. Les proteines au sein de chaque clade presentent des sequences et des structures specifiques de chaque clade, ce qui suggere que le meme motif pourrait servir a differentes fins dans divers contextes. Les profils d'expression des genes UvGATA a differents stades d'infection et en conditions de stress au [H.sub.2][O.sub.2] ont ete caracterises. Les resultats ont montre que la majorite des genes UvGATA sont impliques dans ces deux processus, ce qui confirme les roles de ces genes a la fois en matiere de pathogenicite et en matiere de reponse aux derives actifs de l'oxygene. Cette etude fournit une assise importante pour explorer plus avant les fonctions biologiques des genes UvGATA et d'accroitre la comprehension de leurs mecanismes de regulation transcriptionnelle chez l'U. virens. [Traduit par la Redaction] Mots-cles : Ustilaginoidea virens, domaine GATA, domaine conserve, analyse d'expression., Introduction Rice false smut (RFS) disease caused by Ustilaginoidea virens (teleomorph: Villosiclava virens) is currently a destructive rice disease worldwide. Ustilaginoidea virens infects individual grains at the rice-booting stage (Tang [...]

Ras GTPase‐activating proteins (Ras GAPs) act as negative regulators for Ras proteins and are involved in various signalling processes that influence cellular functions. Here, the function of four Ras GAPs, UvGap1 to UvGap4, was identified and analysed in Ustilaginoidea virens, the causal agent of rice false smut disease. Disruption of UvGAP1 or UvGAP2 resulted in reduced mycelial growth and an increased percentage of larger or dumbbell‐shaped conidia. Notably, the mutant ΔUvgap1 completely lost its pathogenicity. Compared to the wild‐type strain, the mutants ΔUvgap1, ΔUvgap2 and ΔUvgap3 exhibited reduced tolerance to H2O2 oxidative stress. In particular, the ΔUvgap1 mutant was barely able to grow on the H2O2 plate, and UvGAP1 was found to influence the expression level of genes involved in reactive oxygen species synthesis and scavenging. The intracellular cAMP level in the ΔUvgap1 mutant was elevated, as UvGap1 plays an important role in maintaining the intracellular cAMP level by affecting the expression of phosphodiesterases, which are linked to cAMP degradation in U. virens. In a yeast two‐hybrid assay, UvRas1 and UvRasGef (Ras guanyl nucleotide exchange factor) physically interacted with UvGap1. UvRas2 was identified as an interacting partner of UvGap1 through a bimolecular fluorescence complementation assay and affinity capture‐mass spectrometry analysis. Taken together, these findings suggest that the UvGAP1‐mediated Ras pathway is essential for the development and pathogenicity of U. virens. [ABSTRACT FROM AUTHOR]

Mobile edge computing (MEC) is considered as a key technology to deal with computing intensive and delay sensitive tasks. However, in disaster response, emergency rescue and other scenarios, it is impossible to quickly deploy edge servers and provide services. Unmanned aerial vehicle (UAV) assisted MEC has attracted much attention because of its simple deployment and strong mobility. However, the computing resources and energy of UAV are limited, how to allocate resources becomes a difficult problem. To solve this problem, a strategy of efficient utilization resources with multi- UAV cooperation (LUAVs-Cor) is proposed. This strategy dynamically processes tasks through the multi-UAV cooperation. In order to make full use of computing resources of UAVs, the task transmission strategy is determined by searching for the optimal task combination. In addition, the number of UAVs dispatched is optimized according to the UAV processing capacity, the number of tasks and the processing status of tasks, which achieves dynamic deployment of UAVs and reduces energy consumption. By simulation experiments, it is concluded that the service capacity of LUAVs-Cor strategy has been increased by about 6.8%, and the overall energy consumption of UAV has been reduced by 10.3%. LUAVs-Cor strategy has a low collaboration cost and serves more users at a lower energy cost. [ABSTRACT FROM AUTHOR]