Biodiversity estimation of the western region of Ghana using arthropod mean morphospecies abundance

There is a global consensus on the fact that human activities are increasingly eroding biodiversity, especially in many ecologically rich regions of the world. Quantifying these biodiversity losses over large administrative areas, along with the impacts of the respective driving factors is necessary for biodiversity conservation. In this study, we used readily available spatial data on infrastructure, fragmentation, and land use together with ecological data on terrestrial arthropods (as species surrogate) to carry out spatial assessment and mapping of biodiversity values in the Western Region of Ghana, a highly degraded part of the West African biodiversity hotspot. Compared with its pristine condition, our results show that the region has a remaining mean species abundance (MSA) of approximately 52%, indicating a loss of 48% due to anthropogenic activities (mainly cocoa and oil palm farming). Areas of national protection (i.e. national parks and forest reserves) did not prove to have much promise for biodiversity conservation in the region since many were found to have low MSA values. Moreover, according to our arthropod data, no areas of high MSA values were found outside protected areas. However, because the thick, continuous, structurally complex canopies of these orchards responsible for the biodiversity loss provide natural connectivity between protected reserves, diversification of understory vegetation and a reduction in the use of agrochemicals particularly weedicides and pesticides may yield significant conservation outcomes.     

Phenolic compounds isolated from Dioscorea zingiberensis protect against pancreatic acinar cells necrosis induced by sodium taurocholate

One new bibenzyl (1) and one new phenanthrene (2), together with two known bibenzyls (3–4) and four known diarylheptanoids (5–8) were isolated from the rhizomes of Dioscorea zingiberensis. The structures of 1–2 were elucidated by spectroscopic methods including 1D and 2D NMR. Phenols 1–8 were evaluated for their anti-pancreatitic activities on sodium taurocholate (NaT)-induced pancreatic acinars necrosis. Notably, 0.5 mM of compound 6 exhibited comparable inhibitory effect with 5 mM of caffeine. Furthermore, compound 6 prevented the ATP depletion and excessive ROS production which could be also involved in mitochondria-mediated injuries in acute pancreatitis. As a result, compound 6 has been demonstrated to be a potential candidate for mediating mitochondrial dysfunction to prevent pancreatic necrosis. This study is also the first report on the isolation of bibenzyls and diarylheptanoids from this plant.     

Design,synthesis, and biological activity of novel tetrahydropyrazolopyridone derivatives as FXa inhibitors with potent anticoagulant activity

A series of novel tetrahydropyrazolopyridone derivatives containing 1,3,4-triazole, triazolylmethyl, and partially saturated heterocyclic moieties as P2 binding element was designed, synthesized, and evaluated in vitro for anticoagulant activity in human and rabbit plasma. All compounds showed moderate to significant potency, and compounds 15b, 15c, 20b, 20c, and 22b were further examined for their inhibitory activity against human FXa in vitro. While compounds 15c and 22b were tested for rat venous thrombosis in vivo. The most promising compound 15c, with an IC₅₀ (FXa) value of 0.14 μM and 98% inhibition rate, warranted further investigation as an FXa inhibitor.     

The complete chloroplast genome sequence and phylogenetic analysis of <Emphasis Type="Italic">Chuanminshen</Emphasis> (<Emphasis Type="Italic">Chuanminshenviolaceum</Emphasis> Sheh et Shan)

Chloroplast genome sequences are very useful for species identification and phylogenetics. Chuanminshen (Chuanminshen violaceum Sheh et Shan) is an important traditional Chinese medicinal plant, for which the phylogenetic position is still controversial. In this study, the complete chloroplast genome of Chuanminshen violaceum Sheh et Shan was determined. The total size of Chuanminshen chloroplast genome was 154,529 bp with 37.8% GC content. It has the typical quadripartite structure, a large single copy (17,800 bp) and a small single copy (84,171 bp) and a pair of inverted repeats (26,279 bp). The whole genome harbors 132 genes, which includes 85 protein coding genes, 37 tRNA genes, eight rRNA genes, and two pseudogenes. Thirty-nine SSR loci, 32 tandem repeats and 49 dispersed repeats were found. Phylogenetic analyses results with the help of MEGA showed a new insight for the Chuanminshen phylogenetic relationship with the reported chloroplast genomes in Apiales plants.     

<Emphasis Type="Italic">ccaA</Emphasis> and <Emphasis Type="Italic">FBP/SBPase</Emphasis> Derived From Cyanobacteria Improved Photosynthetic Capacity in Rice

Two cyanobacterial genes ccaA and FBP/SBPase related to CO₂ hydration and Calvin cycle were induced into rice plants. Three homologous transgenic strains were generated with ccaA and FBP/SBPase alone or in combination independently and grown under field conditions. The biochemical, physiological, and leaf anatomic results indicated that stomatal and mesophyll conductance to CO₂, net photosynthetic rate, carboxylation efficiency, and other physiological and biochemical parameters increased significantly in the overexpression strains with FBP/SBPase and CcaA + FBP/SBPase but not in the CcaA strain. Leaf anatomy structure showed no significant modifications between the transgenic and wild-type strains. The CcaA protein was shown to be located in the cytoplasm. These results showed that the effect on improving photosynthetic capacity by FBP/SBPase was better than by CcaA, and only when CcaA was co-transformed with FBP/SBPase was the synergistic effect observed. The multigene-stacking approaches and their synergistic action for improving the photosynthetic capacity in rice are discussed.     

Predicting the helix‐helix interactions from correlated residue mutations

Helix‐helix interactions are crucial in the structure assembly, stability and function of helix‐rich proteins including many membrane proteins. In spite of remarkable progresses over the past decades, the accuracy of predicting protein structures from their amino acid sequences is still far from satisfaction. In this work, we focused on a simpler problem, the prediction of helix‐helix interactions, the results of which could facilitate practical protein structure prediction by constraining the sampling space. Specifically, we started from the noisy 2D residue contact maps derived from correlated residue mutations, and utilized ridge detection to identify the characteristic residue contact patterns for helix‐helix interactions. The ridge information as well as a few additional features were then fed into a machine learning model HHConPred to predict interactions between helix pairs. In an independent test, our method achieved an F‐measure of ～60% for predicting helix‐helix interactions. Moreover, although the model was trained mainly using soluble proteins, it could be extended to membrane proteins with at least comparable performance relatively to previous approaches that were generated purely using membrane proteins. All data and source codes are available at http://166.111.152.91/Downloads.html or https://github.com/dpxiong/HHConPred .     

Fisetin provides antidepressant effects by activating the tropomyosin receptor kinase B signal pathway in mice

Depression has been associated with a low‐grade chronic inflammatory state, suggesting a potential therapeutic role for anti‐inflammatory agents. Fisetin is a naturally occurring flavonoid in strawberries that has anti‐inflammatory activities, but whether fisetin has antidepressant effects is unknown. In this study, we exposed mice to spatial restraint for 2 weeks with or without treatment with fisetin. Immobility time in the forced swimming and tail suspension test after this restraint increased in the untreated group, but this increase did not occur in the fisetin group. We administered fisetin to Abelson helper integration site‐1 (Ahi1) knockout mice, which have depressive phenotypes. We found that fisetin attenuated the depressive phenotype of these Ahi1 knockout mice. We further investigated the potential mechanism of fisetin's antidepressant effects. Because TrkB is a critical signaling pathway in the mechanisms of depression, we examined whether phosphorylated TrkB was involved in the antidepressant effects of fisetin. We found that fisetin increased phosphorylated TrkB level without altering total TrkB; this increase was attenuated by K252a, a specific TrkB inhibitor. Taken together, our results demonstrated that fisetin may have therapeutic potential for treating depression and that this antidepressant effect may be mediated by the activation of the TrkB signaling pathway.

     

QTL mapping of root traits in phosphorus-deficient soils reveals important genomic regions for improving NDVI and grain yield in barley

Key message

Major QTLs for root rhizosheath size are not correlated with grain yield or yield response to phosphorus. Important QTLs were found to improve phosphorus efficiency.

Abstract

Root traits are important for phosphorus (P) acquisition, but they are often difficult to characterize and their breeding values are seldom assessed under field conditions. This has shed doubts on using seedling-based criteria of root traits to select and breed for P efficiency. Eight root traits were assessed under controlled conditions in a barley doubled-haploid population in soils differing in P levels. The population was also phenotyped for grain yield, normalized difference vegetation index (NDVI), grain P uptake and P utilization efficiency at maturity (PutE_GY) under field conditions. Several quantitative traits loci (QTLs) from the root screening and the field trials were co-incident. QTLs for root rhizosheath size and root diameter explained the highest phenotypic variation in comparison to QTLs for other root traits. Shared QTLs were found between root diameter and grain yield, and total root length and PutE_GY. A common major QTL for rhizosheath size and NDVI was mapped to the HvMATE gene marker on chromosome 4H. Collocations between major QTLs for NDVI and grain yield were detected on chromosomes 6H and 7H. When results from BIP and MET were combined, QTLs detected for grain yield were also those QTLs found for NDVI. QTLs qGY5H, qGY6H and qGY7Hb on 7H were robust QTLs in improving P efficiency. A selection of multiple loci may be needed to optimize the breeding outcomes due to the QTL x Environment interaction. We suggest that rhizosheath size alone is not a reliable trait to predict P efficiency or grain yield.