Fairy Lake Botanical Garden

Mitochondrial genome evolution(MGE) in flowering plants is quasi-intertwined-dynamic. MGE is driven via mutational pressures, translational selection, and functional constraints. However, unveiling the intra- and inter-genomic interplay governing evolutionary drives remains challenging. We investigate MGE-dynamic across twelve Gentianales species, revealing distinct codon usage patterns influenced by opposing evolutionary forces. While the first and second codon positions are highly conserved, the third codon positions show significant variability (27.7% - 45.8%), reflecting diverse selective pressures. Multi-dimensional analyses, including ENc-GC3s plots, neutrality plots, and PR2 bias, indicate that natural selection predominantly governs codon usage, outweighing mutational biases. Key findings include, non-significant correlations between GC12 and GC3 (R2 ≤ 0.21), suggesting minimal mutational impact on genome composition; ENc-GC12 analysis showing codon optimization results from both selection and mutation; and PR2-plot analysis highlighting a preference for T- and G-ending codons, indicative of translational efficiency constraints. Gene-specific analyses of substitution rates (dN, dS, and dN/dS ) uncover heterogeneous selective landscapes, with genes such as atp, ccm, nad, and rps exhibiting signatures of positive selection. Substantial mutually offsetting dynamics between T3s and C3s (r = - 0.73), coupled with strong correlations between G3s and translational-efficiency indices (CAI: r = 0.69; CBI: r = 0.65), underscore that third-codon biases optimize translation. Evolutionary rates (dS and dN/dS ) show positive correlations with GC3 content (r = 0.45 and r = 0.33, respectively), indicating the influence of nucleotide composition on synonymous substitutions. Thus, these results reveal the interplay of the mutation-selection balance in non-recombining genomes and offer new perspectives on mitochondrial diversity in flowering plants.

Acteoside, a phenylethanol glycoside, possesses various pharmacological properties. The aim of this study was to investigate the mechanism of its anti-obesity effects on high-fat diet (HFD)-induced obese mice, as well as to evaluate the anti-obesity effects of its two active metabolites, caffeic acid and hydroxytyrosol. Mice were randomly divided into six groups in the first part experiment and five groups in the second part experiment as follows: control diet group; control diet + acteoside at 150mg/kg/day group; HFD group; HFD + orlistat at 20mg/kg/day group; HFD + caffeic acid at 45mg/kg/day group; HFD + hydroxytyrosol at 40mg/kg/day group; HFD + acteoside at 75mg/kg/day group; and HFD + acteoside at 150mg/kg/day group. The results showed that acteoside exhibited more pronounced anti-obesity effects compared with its two active metabolites. Acteoside supplementation reduced body weight and white adipose tissue (WAT) weight and improved glucose tolerance and insulin sensitivity in obese mice, as well as partially reverse hepatic damage and fat accumulation. In addition, acteoside induced the production of brown adipose tissue (BAT) when compared with caffeic acid and hydroxytyrosol, as well as promote a thermogenesis program in BAT and activate AMPK and HSL signaling in both WAT and BAT. Furthermore, high-dose acteoside supplementation altered the gut microbiota by increasing the abundance of Akkermansia muciniphila in obese mice. In summary, our results indicate that long-term acteoside supplementation may partially reverse obesity by stimulating adipose thermogenesis, modulating lipid metabolism, and altering the gut microbiota.

Abstract Encephalartos , an African endemic genus within the Zamiaceae, comprises 65 extant species whose phylogenetic relationships have remained unresolved due to limited genetic differentiation observed in previous studies. This research reconstructs the evolutionary history of Encephalartos utilizing 3545 single‐copy nuclear genes derived from transcriptomes of 64 species. The study estimates divergence times and reconstructs ancestral states for 12 key morphological traits. Phylogenetic analyses definitively resolve eight major clades, supported by both molecular and morphological evidence. Although these clades partially align with previous morphology and geography based classifications, the genomic data provide novel insights, necessitating a revised infrageneric system. Biogeographic reconstructions indicate that Encephalartos originated in southern Africa during the Oligocene (~26.3 Ma), subsequently dispersing into eastern and northern Africa through the Zimbabwe–Mozambique corridor during the Miocene, followed by expansion into Central Africa. Speciation rates decreased markedly during the Pliocene and Pleistocene, potentially due to intensified climatic drying and cooling. Morphological character mapping identified ancestral traits, including aerial stems, green leaves, and red sarcotesta. Specific transitions such as subterranean stems in clade IV and bluish‐green leaves in clades II and V, further substantiate clade differentiation. These findings resolve long‐standing taxonomic uncertainties and emphasize the Oligocene‐Miocene as a crucial period for Encephalartos diversification, influenced by Cenozoic climate change. This research establishes a robust framework for future systematic and conservation studies while demonstrating the effectiveness of transcriptome data in resolving phylogenies of slowly evolving lineages.

Global change seriously affects human survival, and urban forests can improve human living environments and mitigate the negative impacts of global change. The spatial distribution of carbon and nitrogen is key to assessing the health of forest ecosystems. However, the mechanism underlying the spatial distribution of carbon and nitrogen in urban forests in subtropical regions remains unclear. To study the characteristics and factors influencing the carbon and nitrogen contents of forest soils in Shenzhen, 126 soil samples were collected. Multivariate statistics and spatial analysis methods revealed the spatial distribution patterns and influencing factors of SOC, TN, and C/N in Shenzhen forest soils. The results showed the following: (1) The mean values of SOC, TN, and C/N of the 0–10 cm soil were 18.32 g·kg−1, 1.29 g·kg−1 and 14.43, with coefficients of variation (CVs) of 38.21%, 37.98%, and 15.73%, respectively, and those of the 10–30 cm soil were 9.24 g·kg−1, 0.67 g·kg−1, and 13.75, with CVs of 45.24%, 41.79%, and 19.45%, respectively. (2) The kriging spatial interpolation showed that the high- and low-value areas of 0–10 cm SOC and TN were concentrated in the northwestern and central and northern parts of the study area, respectively. The high value areas of 10–30 cm SOC and TN expanded to the southeastern part of the study area, and the low-value areas of SOC were distributed in the northern part. (3) The edges of the study area were fragmented, and the low-value areas of TN were mainly distributed in the western region, the high-value areas of C/N were mainly distributed in the west, and the low-value areas were mainly distributed at the eastern edge. Soil bulk weight and conductivity were the key factors affecting SOC and TN, which were the key factors affecting C/N. We emphasized the inhomogeneity of the spatial distribution of C/N in the subtropical region and that soil C/N is co-regulated by multiple factors. The results may provide insights for the government’s urban green space construction.

Arbuscular mycorrhizal fungi (AMF) are symbiotic fungi that associate with the vast majority of terrestrial plants. Among non-vascular plants, while AMF associations are well-documented in liverworts and hornworts, there is a broad consensus that symbiotic associations do not occur in mosses. Here, we report the presence of AMF in the living material of mosses found in Chaco Serrano (Tucumán, Argentina). We found all characteristic structures of AMF when establishing an intimate connection with two moss species of Pottiaceae (Bryophyta). While Gertrudiella uncinicoma exhibited AMF with both Arum- and Paris-type morphologies, Pleurochaete luteola only displayed an Arum-type morphology. Plant tissue samples were subjected to high-throughput sequencing for AMF identification. We determined that Rhizophagus irregularis was a clear dominant species in both moss species, with Glomus sp. also being present as a less abundant element. In addition, we also reported the presence of vesicles, arbuscules, and spores adhered to the hyphae and the presence of septate endophytes. This finding expands our understanding of the interactions between AMF and non-vascular plants and prompt us to further characterize this interaction by considering the diversity of mycorrhizal associations with concurrent implications for the ecology of mosses and the functionality of the ecosystems.

Understanding how anthropogenic disturbances affect the genetics of tree species is crucial; however, how tree populations in the wild can tolerate these activities remains unexplored. Given the ongoing and intensifying anthropogenic disturbances, we conducted a study using Ailanthus altissima to gain new insights into the effects of these pressures on genetic variability in undisturbed and disturbed forests. We analyzed the genetic diversity and population structure of A. altissima using nuclear (EST-SSR) and chloroplast (cpSSR) microsatellite markers. The genetic diversity across the 34 studied populations based on EST-SSRs was found to be moderate to high (nHE = 0.547–0.772) with a mean nHE of 0.680. Bayesian clustering, principal coordinate analysis (PCoA), and discriminant analysis of principal component (DAPC) consistently divided the populations into three distinct groups based on EST-SSRs. Allelic combinations of 92 different chloroplast size variants from 10 cpSSR loci resulted in a total of 292 chloroplast haplotypes. The mean haplotype diversity was relatively high (cpHE = 0.941), and the mean haplotype richness was 2.690, averaged across the 34 populations of A. altissima. Values of FST in A. altissima from chloroplast and nuclear markers were 0.509 and 0.126, respectively. Modeling results showed evidence for population range contraction during the Last Glacial Maximum with subsequent population expansion in the Holocene and the future. Although genetic variation did not differ substantially across disturbed and undisturbed sites, there were small trends indicating higher genetic diversity and population bottlenecks in disturbed forests. As a result, disrupted ecosystems might display surprising genetic patterns that are difficult to predict and should not be overlooked.

A novel cyanobacterial strain (CSML-F035) here described as Stenomitos nagquensis sp. nov. was isolated from a plateau meadow wetland habitat in the Tibet Autonomous Region. The novel strain was studied based on a polyphasic approach by combining characteristics of cell morphology and evidence from molecular data and ecology. Phylogenetic analyses based on the 16S rRNA and rbcL genes indicated that the novel strain is a member of the genus Stenomitos (Leptolyngbyaceae) but is positioned in a unique clade, with strongly supported values from BI, ML, and NJ methods. The percentage similarity of the 16S rRNA gene sequence of CSML-F035 compared with known strains of Stenomitos was >97%. Morphologically, S. nagquensis sp. nov. possesses overlapping morphological characteristics with other Stenomitos species, with thin trichomes enclosed in a firm, colorless, hyaline, persistent mucilage. However, the strain appeared to have slightly smaller cells compared to most known species of Stenomitos. Further analyses of the 16S–23S ITS region showed dissimilarity at 11.2–22.8% compared to known species of Stenomitos. The secondary helices—including D1–D1, V2, Box–B, and V3—that were predicted based on the 16S–23S ITS region for Stenomitos nagquensis sp. nov. were also distinct, thereby providing strong additional support for the separation of this species. This study highlights the importance of unexplored habitats in the Tibet region in which cyanobacterial diversity can be deemed high, with many potential new species that remain poorly explored.

The moss Physcomitrium patens is crucial for studying plant development and evolution. Although the P. patens genome includes genes acquired from bacteria, fungi and viruses, the functions and evolutionary significance of these acquired genes remain largely unclear. Killer protein 4 (KP4) is a toxin secreted by the phytopathogenic fungus Ustilago maydis that inhibits the growth of sensitive target strains by blocking their calcium uptake. Here, we show that KP4 genes in mosses were acquired from fungi through at least three independent events of horizontal gene transfer. Two paralogous copies of KP4 (PpKP4-1 and PpKP4-2) exist in P. patens. Knockout mutants ppkp4-1 and ppkp4-2 showed cell death at the protonemal stage, and ppkp4-2 also exhibited defects in tip growth. We provide experimental evidence indicating that PpKP4-1/2 affects P. patens protonemal cell development by mediating cytoplasmic calcium and that KP4 genes are functionally conserved between P. patens and fungi. The present study provides additional insights into the role of horizontal gene transfer in land plant development and evolution.