Predicting the response of three common subtropical tree species in China to climate change

IntroductionClimate is crucial factor influencing species distribution, and with global climate change, the potential geographic distribution of species will also alter. In this study, three subtropical tree species (Cunninghamia lanceolata, Pinus taiwanensis, and Quercus glauca) of great ecological values were selected as research objects.MethodsWe applied a maximum entropy (MaxEnt) to predict their potential distributions under different climate scenarios in both present and future conditions based on 37 environmental factors. Jackknife test was used in key factors affecting species distribution. In addition, we explored the key environmental variables that affect their distributions and revealed the evolutionary patterns and migration trends of these tree species under future climate.ResultsThe main findings are as follows: (1) Winter temperature, winter precipitation, and annual temperature range are identified as the key environmental variables affecting the potential geographic distribution of the three tree species; moreover, precipitation-related factors have a greater impact than temperature-related factors; (2) Currently suitable habitats for these three tree species are primarily located in subtropical China with decreasing suitability from south to north; (3) Under future climate conditions, the area of potentially suitable habitat for C. lanceolata continues to expand, while P. taiwanensis and Q. glauca tend to experience a reduction due to increasing greenhouse gas emissions over time; and (4) The centroid of suitable habitat for C. lanceolata shifts northward under future climate change, while the centroid of P. taiwanensis and Q. glauca move southward along with shrinking suitable habitat area.DiscussionOur predictions highlight a high risk of habitat loss of Q. glauca under climate change, recommending management and conservation references for these three commonly used afforestation species under current and future climate change scenarios in China

AI is a viable alternative to high throughput screening: a 318-target study

: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

Probucol Nanostructured Lipid Carrier Ameliorates Elastase-induced Abdominal Aortic Aneurysm in Mice: Probucol nanostructured lipid carrier ameliorates abdominal aortic aneurysm

Probucol (PB) is a drug commonly used for the treatment of hyperlipidemia and atherosclerosis. In our previous study, we have proved that PB can ameliorate abdominal aortic aneurysm (AAA) induced by elastase in mice through its anti-inflammatory and anti-oxidative effect. In this study, the water solubility and oral absorption of PB were improved by encapsulating PB into nanostructured lipid carriers (PB-NLC), and the effects of NLC on the anti-AAA effects of PB were evaluated and compared to the PB free drug. AAA mouse model was constructed by incubating the mouse aorta with elastase. Mice in the drug-treated groups were given PB free drug or PB-NLC at a PB dose of either 10 mg/kg or 20 mg/kg daily, and mice in the model group were treated with saline. The arterial wall and the degradation grade of the elastic lamina were investigated by HE staining and aldehyde fuchsine staining of the aortic sections. Infiltration of macrophages and degree of inflammation were evaluated by immunohistochemical staining of CD68 and TNFα, respectively, in the aortic sections. In addition, the absorption improvement of PB by the NLC nano-formulation was evaluated through determining and comparing the steady-state plasma concentration of PB in the PB free drug or PB-NLC treated mice group. When treating the mice with AAA with an equal dose of PB, PB-NLC more significantly inhibited expansion of the abdominal aortas and maintained the integrity of the aortic walls, compared with the PB free drug. The NLC nano-formulation significantly increased the steady-state plasma concentration of PB. PB-NLC significantly increased the absorption and protective effects of PB against elastase-induced AAA in mice

Effect of Simulated Organic–Inorganic N Deposition on Leaf Stoichiometry, Chlorophyll Content, and Chlorophyll Fluorescence in <i>Torreya grandis</i>

Atmospheric nitrogen (N) deposition is coupled with organic nitrogen (ON) and inorganic nitrogen (IN); however, little is known about plant growth and the balance of elements in Torreya grandis growing under different ON/IN ratios. Here, we investigated the effects of ON/IN ratios (1/9, 3/7, 7/3, and 9/1) on leaf stoichiometry (LF), chlorophyll content, and chlorophyll fluorescence of T. grandis. We used ammonium nitrate as the IN source and an equal proportion of urea and glycine as the ON source. The different ON/IN ratios altered the stoichiometry and photochemical efficiency in T. grandis. Although the leaf P content increased significantly after treatment, leaf N and N:P maintained a certain homeostasis. Torreya grandis plants performed best at an ON/IN ratio of 3/7, with the highest values of chlorophyll-a, total chlorophyll, maximum photochemical efficiency, and photosynthetic performance index. Thus, both ON and IN types should be considered when assessing the responses of plant growth to increasing N deposition in the future. Our results also indicated that the leaf P concentration was positively correlated with Chl, Fv/Fm, and PIabs. This result further indicates the importance of the P element for plant growth against the background of nitrogen deposition. Overall, these results indicate that T. grandis might cope with changes in the environment by maintaining the homeostasis of element stoichiometry and the plasticity of PSII activity

Empirical Subseasonal Prediction of Summer Rainfall Anomalies over the Middle and Lower Reaches of the Yangtze River Basin Based on Atmospheric Intraseasonal Oscillation

The middle and lower reaches of the Yangtze River basin (MLRYB) are prone to flooding because their orientation is parallel to the East Asian summer monsoon rain belt. Since the East Asian summer monsoon presents pronounced intraseasonal variability, the subseasonal prediction of summer precipitation anomalies in the MLRYB region is an imperative demand nationwide. Based on rotated empirical orthogonal function analysis, 48 stations over the MLRYB with coherent intraseasonal (10–80-day) rainfall variability are identified. Power spectrum analysis of the MLRYB rainfall index, defined as the 48-station-averaged intraseasonal rainfall anomaly, presents two dominant modes with periods of 20–30 days and 40–60 days, respectively. Therefore, the intraseasonal (10–80-day) rainfall variability is divided into 10–30-day and 30–80-day components, and their predictability sources are detected separately. Spatial-temporal projection models (STPM) are then conducted using these predictability sources. The forecast skill during the period 2003–2010 indicates that the STPM is able to capture the 30–80-day rainfall anomalies 5–30 days in advance, but unable to reproduce the 10–30-day rainfall anomalies over MLRYB. The year-to-year fluctuation in forecast skill might be related to the tropical Pacific sea surface temperature anomalies. High forecasting skill tends to appear after a strong El Niño or strong La Niña when the summer seasonal mean rainfall over the MLRYB is enhanced, whereas low skill is apparent after neutral conditions or a weak La Niña when the MLRYB summer seasonal mean rainfall is weakened. Given the feasibility of STPM, the application of this technique is recommended in the real-time operational forecasting of MLRYB rainfall anomalies during the summer flooding season

Interaction Analysis of Odorant-Binding Protein 12 from <i>Sirex noctilio</i> and Volatiles from Host Plants and Symbiotic Fungi Based on Molecule Dynamics Simulation

As a quarantine pest of conifer, Sirex noctilio has caused widespread harm around the world. It is expected that the molecular mechanism of protein–ligand binding can be elucidated to carry out the pest control. Through studies of SnocOBP12–ligand hydrophobic binding and dynamics and responsible amino acid residues identification, we got some promising results. SnocOBP12 had a general and excellent affinity for host plant volatiles, and may be a key protein for S. noctilio to find host plants. Among the many odor molecules that are bound to SnocOBP12, (−)-α-cedrene and (E)-β-farnesene from host plants and (−)-globuol from the symbiotic fungi of Sirex noctilio stood out and formed highly stable complexes with SnocOBP12. By the molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) method, the calculated free binding energy of the three complexes was −30.572 ± 0.101 kcal/mol, −28.349 ± 0.119 kcal/mol and −25.244 ± 0.152 kcal/mol, respectively. It was found that the van der Waals energy contributed to the stability of the complexes. Some key amino acid residues were also found: LEU74 and TYR109 were very important for SnocOBP12 to stably bind (−)-α-cedrene, while for (E)-β-farnesene, ILE6, MET10, and LEU74 were very important for the stable binding system. We discovered three potential ligands and analyzed the interaction pattern of the protein with them, this paper provides a favorable molecular basis for optimizing the attractant formulation. Investigation of the binding characteristics in the olfactory system at the molecular level is helpful to understand the behavior of S. noctilio and develop new methods for more effective and environmentally friendly pest control

Application of Molecular Marker Technology in the Study of Forest Tree Species

Due to its unique advantages, molecular marker technology is widely applied in the research of forest tree species. This paper reviewed the application of molecular marker technology in tree species resource diversity, germplasm identification, genetic map construction, gene mapping and marker-assisted selection (MAS) breeding. In addition, it elaborated the great significance of molecular marker technology to promote the sustainable development of forestry production in China