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The family Filoviridae comprises many notorious viruses, such as Ebola virus (EBOV) and Marburg virus (MARV), that can infect humans and nonhuman primates. Lloviu virus (LLOV), a less well studied filovirus, is considered a potential pathogen for humans. The VP30 C-terminal domain (CTD) of these filoviruses exhibits nucleoprotein (NP) binding and plays an essential role in viral transcription, replication and assembly. In this study, we confirmed the interactions between LLOV VP30 CTD and its NP fragment, and also determined the crystal structure of the chimeric dimeric LLOV NP-VP30 CTD at 2.50 Å resolution. The structure is highly conserved across the family Filoviridae. While in the dimer structure, only one VP30 CTD binds the NP fragment, which indicates that the interaction between LLOV VP30 CTD and NP is not strong. Our work provides a preliminary model to investigate the interactions between LLOV VP30 and NP and suggests a potential target for anti-filovirus drug development.

Lianas are woody plants that require external support to reach the canopy. They are expanding in forests worldwide, possibly due to climate change and forest disturbance. Most studies on lianas have been conducted in tropical forests. Lianas are less explored in subtropical forests. We aimed to document the density and diversity of lianas, to test how habitat condition and the distribution of tree species affect the distributions of lianas based on data from a fully mapped 20 ha plot in subtropical China. We analyzed habitat association by fitting a generalized linear model with family-level liana abundance as response variable and family identity, and its interaction terms with topographic variables (slope, convexity, elevation, and sin(aspect)), as explanatory variables. We focused on the spatial associations of three liana species and 82 tree species with ≥100 individuals using the pair correlation function and redundancy analysis. We found a total of 1305 lianas, falling into 26 species, and 16 families, in the 20 ha plot. They accounted for 1.5% of individuals, 11.7% of species, and 0.4% of total basal area of woody plants in the plot. There were large variations in distributions of liana with respect to the four topographic variables among families, contrasting with former findings suggesting that lianas favor dry and hot habitats. The three most abundant liana species showed non-random associations with tree species, and they tended to positively associate with similar tree species but negatively associate with different tree species. The distribution of tree species explained 21.8% of variance in liana distribution. Our study suggested that both habitat conditions and tree composition intervene in determining liana distributions and that habitat heterogeneity may be a mechanism for liana diversity maintenance. Our study provides a basic understanding of liana diversity and distribution in this subtropical forest and contributes to future planning of liana studies and diversity conservation in subtropical forests under climate change.

Arbuscular mycorrhizal (AM) and ectomycorrhizal (EcM) associations are critical for host-tree performance. However, how mycorrhizal associations correlate with the latitudinal tree beta-diversity remains untested. Using a global dataset of 45 forest plots representing 2,804,270 trees across 3840 species, we test how AM and EcM trees contribute to total beta-diversity and its components (turnover and nestedness) of all trees. We find AM rather than EcM trees predominantly contribute to decreasing total beta-diversity and turnover and increasing nestedness with increasing latitude, probably because wide distributions of EcM trees do not generate strong compositional differences among localities. Environmental variables, especially temperature and precipitation, are strongly correlated with beta-diversity patterns for both AM trees and all trees rather than EcM trees. Results support our hypotheses that latitudinal beta-diversity patterns and environmental effects on these patterns are highly dependent on mycorrhizal types. Our findings highlight the importance of AM-dominated forests for conserving global forest biodiversity., The relationship of mycorrhizal associations with latitudinal gradients in tree beta-diversity is unexplored. Using a global dataset approach, this study examines how trees with arbuscular mycorrhizal and ectomycorrhizal associations contribute to latitudinal beta-diversity patterns and the environmental controls of these patterns.