High auxin stimulates callus through SDG8-mediated histone H3K36 methylation in Arabidopsis

Callus induction,which results in fate transition in plant cells,is considered as the first and key step for plant regeneration.This process can be stimulated in different tissues by a callus-inducing medium(CIM),which contains a high concentration of phytohormone auxin.Although a few key regulators for callus induction have been identified,the multiple aspects of the regulatory mechanism driven by high levels of auxin still need further investigation.Here,we find that high auxin induces callus ...     

Fast seedling root growth leads to competitive superiority of invasive plants

The competitive superiority of invasive plants plays a key role in the process of plant invasions, enabling invasive plants to overcome the resistance of local plant communities. Fast aboveground growth and high densities lead to the competitive superiority of invasive species in the competition for light. However, little is understood of the role belowground root competition may play in invasion. We conducted an experiment to test the effect of root growth on the performance of an invasive shrub Cassia alata, a naturalized, non-invasive shrub Corchorus capsularis, and a native shrub Desmodium reticulatum. We compared seedling growth of the three species and their competitive ability in situ. The roots of the C. alata seedlings grew much faster than those of C. capsularis and D. reticulatum during the entire growth period although C. alata had shorter shoots than D. reticulatum. Furthermore, C. alata showed an apparent competition advantage compared to the other two species as evidenced by less biomass reduction in intraspecific competition and higher competitive effects in interspecific competition. Our study reveals that fast seedling root growth may be important in explaining the competitive advantages of invasive plants. Future studies should pay more attention to the belowground traits of invasive plants, the trade-off between shoot and root growth, and the role of root competition in affecting the population dynamics of invasive plants and the structures of invaded communities.     

Identification of a 4-fluorobenzyl l-valinate amide benzoxaborole (AN11736) as a potential development candidate for the treatment of Animal African Trypanosomiasis (AAT)

Novel l-valinate amide benzoxaboroles and analogues were designed and synthesized for a structure-activity-relationship (SAR) investigation to optimize the growth inhibitory activity against Trypanosoma congolense (T. congolense) and Trypanosoma vivax (T. vivax) parasites. The study identified 4-fluorobenzyl (1-hydroxy-7-methyl-1,3-dihydrobenzo[c][1,2]oxaborole-6-carbonyl)-l-valinate (5, AN11736), which showed IC₅₀ values of 0.15?nM against T. congolense and 1.3?nM against T. vivax, and demonstrated 100% efficacy with a single dose of 10?mg/kg against both T. congolense and T. vivax in mouse models of infection (IP dosing) and in the target animal, cattle, dosed intramuscularly. AN11736 has been advanced to early development studies.     

Discovery of 3-(4-sulfamoylnaphthyl)pyrazolo[1,5-a]pyrimidines as potent and selective ALK2 inhibitors

The pyrazolo[1,5-a]pyrimidine LDN-193189 is a potent inhibitor of activin receptor-like kinase 2 (ALK2) but is nonselective for highly homologous ALK3 and shows only modest kinome selectivity. Herein, we describe the discovery of a novel series of potent and selective ALK2 inhibitors by replacing the quinolinyl with a 4-(sulfamoyl)naphthyl, yielding ALK2 inhibitors that exhibit not only excellent discrimination versus ALK3 but also high kinome selectivity. In addition, the optimized compound 23 demonstrates good ADME and in vivo pharmacokinetic properties.     

Design,synthesis and evaluation of 4′-OH-flurbiprofen-chalcone hybrids as potential multifunctional agents for Alzheimer’s disease treatment

A series of 4′-OH-flurbiprofen-chalcone hybrids were designed, synthesized and evaluated as potential multifunctional agents for the treatment of Alzheimer’s disease. The biological screening results indicated that most of these hybrids exhibited good multifunctional activities. Among them, compounds 7k and 7m demonstrated the best inhibitory effects on self-induced Aβ_1–42 aggregation (60.0% and 78.2%, respectively) and Cu²⁺-induced Aβ_1–42 aggregation (52.4% and 95.0%, respectively). Moreover, these two representative compounds also exhibited good antioxidant activities, MAO inhibitions, biometal chelating abilities and anti-neuroinflammatory activities in vitro. Furthermore, compound 7m displayed appropriate blood-brain barrier permeability. These multifunctional properties highlight compound 7k and 7m as promising candidates for further development of multi-functional drugs against AD.     

Cultivable Fungal Diversity in Deep-Sea Sediment of the East Pacific Ocean

The diversity of fungi in the marine environment has been extensively studied, but their denitrification activity has rarely been reported to date. In the present study, we used six different media to isolate fungi from 10 sediment samples collected at five different locations of the East Pacific Ocean with water depths ranging from 4545 to 7068?m. Fungal identification and phylogenetic diversity analysis were conducted based on morphological characteristics and internal transcribed spacers of ribosomal DNA (ITS-rRNA) sequencing. A total of 106 fungal isolates, belonging to 12 genera, including Aspergillus (five strains), Aureobasidium (three strains), Candida (two strains), Cladosporium (56 strains), Cystobasidium (one strain), Devriesia (nine strains), Knufia (one strain), Nigrospora (three strains), Penicillium (18 strains), Rhodotorula (four strains), Sarocladium (three strains), and unclassified Xylariales (one strain) were obtained. The most dominant culturable genus was Cladosporium. One possible novel fungal strains showed less than 97% similarity to their closest matches of unclassified Xylariales in the Genbank. In addition, we used nirK gene as the molecular marker to detect denitrifying fungi among the cultivable fungal isolates. The nirK gene was detected in Aspergillus niger and Penicillium chrysogenum. Our research indicated that diverse fungi from the deep sea sediments of the East Pacific Ocean and highlighted the involvement of these fungi in denitrification process.     

Genetic individualization of sable (Martes zibellina L. 1758) using microsatellites

Genetic individualization based on non-invasive sampling is crucial for estimating the numbers of individuals in endangered mammalian populations. In sable (Martes zibellina)-poaching cases, identifying the number of animals involved is critical for determining the penalty. In addition, investigating animal numbers for wild sable populations requires genetic individualization when collecting several samples in neighboring regions. Microsatellites have been demonstrated to be reliable markers for individual identification. Thirty-three microsatellite loci derived from Mustelidae were selected to develop a genetic individualization method for sable. Three reference populations containing 54 unrelated sables were used to calculate allele number, allelic frequencies, and the polymorphic information content of each locus. The data were subsequently used to assess the validity of a combination of twelve loci for sable individualization. We defined twelve polymorphic loci that were easy to be amplified and genotyped. Four significant deviations from Hardy-Weinberg equilibrium were observed among the 12?loci in the three populations. The match probability of an individual from the reference populations with a random individual based on the 12?loci was 1.37?×?10^?13. Using the combination of the twelve loci provides sufficient power to individualize sables considering the levels of microsatellite polymorphism observed. These loci were successfully applied to a case of sable poaching and provided valid evidence to determine the penalty. The genetic individualization of sable based on these loci might also be useful to investigate the numbers of animals in wild populations.     

Identifying suitable reference genes for developing and injured mouse CNS tissues

Accurate quantification of gene expression is fundamental for understanding the molecular, genetic and functional bases of tissue development and diseases. Quantitative real‐time PCR (qPCR) is now the most widely used method of quantifying gene expression due to its simplicity, specificity, sensitivity, and wide quantification range. The use of appropriate reference genes to ensure accurate normalization is crucial for the correct quantification of gene expression from the early development, maturation, aging to injury processes in the central nervous system (CNS). In this study, we have determined the expression profiles of 12 candidate housekeeping genes (ACTB, CYC1, HMBS, GAPDH, HPRT1, RPL13A, YWHAZ, PPIA, RPLP0, TFRC, GUS, and 18S rRNA) in developing mouse brain and spinal cord. Throughout development, there was a significant degree of fluctuations in their expression levels, indicating the importance and complexity of finding appropriate reference genes. Three software including BestKeeper, geNorm and NormFinder were used to evaluate the stability of potential reference genes. GUS was the most stable gene and GUS/YWHAZ were the most stable reference gene pair across different developmental stages in different CNS regions, whereas HPRT1 and GAPDH were the most variable genes and thus inappropriate to use as reference genes. Therefore, our results identified GUS and YWHAZ as the best combination of two reference genes for expression data normalization in CNS developmental studies. © 2017 Wiley Periodicals, Inc. Develop Neurobiol 78: 39–50, 2018     

Natural variation in GmGBP1 promoter affects photoperiod control of flowering time and maturity in soybean

The present study screened for polymorphisms in coding and non‐coding regions of the GmGBP1 gene in 278 soybean accessions with variable maturity and growth habit characteristics under natural field conditions in three different latitudes in China. The results showed that the promoter region was highly diversified compared with the coding sequence of GmGBP1. Five polymorphisms and four haplotypes were closely related to soybean flowering time and maturity through association and linkage disequilibrium analyses. Varieties with the polymorphisms SNP_‐796G, SNP_‐770G, SNP_‐307T, InDel_‐242normal, SNP_353A, or haplotypes Hap‐3 and Hap‐4 showed earlier flowering time and maturity in different environments. The shorter growth period might be largely due to higher GmGBP1 expression levels in soybean that were caused by the TCT‐motif with SNP_‐796G in the promoter. In contrast, the lower expression level of GmGBP1 in soybean caused by RNAi interference of GmGBP1 resulted in a longer growth period under different day lengths. Furthermore, the gene interference of GmGBP1 also caused a reduction in photoperiod response sensitivity (PRS) before flowering in soybean. RNA‐seq analysis on GmGBP1 underexpression in soybean showed that 94 and 30 predicted genes were significantly upregulated and downregulated, respectively. Of these, the diurnal photoperiod‐specific expression pattern of three significant flowering time genes GmFT2a, GmFT5a, and GmFULc also showed constantly lower mRNA levels in GmGBP1‐i soybean than in wild type, especially under short day conditions. Together, the results showed that GmGBP1 functioned as a positive regulator upstream of GmFT2a and GmFT5a to activate the expression of GmFULc to promote flowering on short days.