Abstract Background Little is known about the potential of Brachypodium distachyon as a model for low temperature stress responses in Pooideae. The ice recrystallization inhibition protein (IRIP) genes, fructosyltransferase (FST) genes, and many C-repeat binding factor (CBF) genes are Pooideae specific and important in low temperature responses. Here we used comparative analyses to study conservation and evolution of these gene families in B. distachyon to better understand its potential as a model species for agriculturally important temperate grasses. Results Brachypodium distachyon contains cold responsive IRIP genes which have evolved through Brachypodium specific gene family expansions. A large cold responsive CBF3 subfamily was identified in B. distachyon , while CBF4 homologs are absent from the genome. No B. distachyon FST gene homologs encode typical core Pooideae FST-motifs and low temperature induced fructan accumulation was dramatically different in B. distachyon compared to core Pooideae species. Conclusions We conclude that B. distachyon can serve as an interesting model for specific molecular mechanisms involved in low temperature responses in core Pooideae species. However, the evolutionary history of key genes involved in low temperature responses has been different in Brachypodium and core Pooideae species. These differences limit the use of B. distachyon as a model for holistic studies relevant for agricultural core Pooideae species.
Magterpenoid A (1), possessing a rare 4,6,11-trioxatricyclo[5.3.1.01,5]undecane framework with an irregular monoterpenoid moiety, magterpenoid B (2), with an unprecedented 6/6/6/6 polycyclic skeleton, and magterpenoid C (3), a novel terpenoid quinone with a C6–C3 unit, were isolated from the bark of Magnolia officinalis var. biloba. Plausible biogenetic pathways of 1-3 are presented. Compounds 1 and 3 exhibited significant PTP1B inhibitory activities with IC50 values of 1.44 and 0.81 μM, respectively.
Saikosaponins are bioactive oleanane saponins derived from the Chinese medicinal herb Radix bupleuri ("chaihu" in Chinese). An LC−MS/MS-based method has been developed for characterization and quantification of 15 saikosaponin derivatives (saikosaponin a, saikosaponin b1, saikosaponin g, saikogenin A, saikogenin H, saikosaponin c, saikosaponin h, saikosaponin i, prosaikogenin C2, prosaikogenin B2, saikogenin C, saikogenin B, saikosaponin d, saikosaponin b2, and saikogenin D) in one chromatographic run. Optimization of the ionization process was performed with electrospray and atmospheric pressure chemical ionization techniques in both positive and negative ion modes. Negative ion ESI was adopted for generation of the precursor deprotonated molecules to achieve the best ionization sensitivity for the analytes. In addition, the most abundant fragment ion was chosen for each analyte to give the best CID sensitivity. Because some of the saponin derivatives are isomeric, complete resolution for the whole analytes was achieved both chromatographically and mass spectroscopically. Furthermore, optimal internal standard was successfully discovered for determination of the analytes by making use of a combinatorial chemistry approach. Good linearity over the range ∼1.65 or 4.98 to 1200 ng/mL for the analytes was observed. The intraday accuracy and precision at nominal low, intermediate, and high concentration varied between 0.8 and 11.8% and between 80 and 116%, respectively, whereas those for interday assay were between 1.1 and 15.5% and between 86 and 119%, respectively. The lower limits of quantitation for the test compounds were ∼16.5 to 49.4 pg on-column. The new method offered higher sensitivity and greater specificity than previously reported LC methods. After the validation, the applicability of the method for determination of these chemicals present in a variety of crude chaihu roots and in different brands of the Chinese multiherb remedy Xiaochaihu-tang (or Shosaiko-to) extract granules has been demonstrated. The sensitivity and specificity of the technique will be the basis of a method for the accurate quantification of the saikosaponin derivatives in biomatrixes.
The water content of maize kernels during harvest is a critical factor influencing grain harvest practices globally. Abscisic acid (ABA) plays a pivotal role in grain development during the grain-filling process. Yet, there has been limited reporting on the regulatory mechanism of grain dehydration induced by exogenous ABA using proteomic techniques. In this study, two maize genotypes with distinct dehydration rates, DK517 (fast dehydration) and ZD1002 (slow dehydration), were treated with ABA after the heading stage. Results revealed a 20% lower yield in DK517 compared to ZD1002 following ABA application. Sixty days after pollination, the grain water content decreased to 23.55% in DK517 and 30.42% in ZD1002 due to ABA treatment. Through proteomic analysis, 861 and 118 differentially expressed proteins (DAPs) were identified in DK517 and ZD1002, respectively, as a result of ABA treatment. GO analysis indicated that the primary metabolic process, nitrogen compound metabolic process, and hormone metabolic process were significantly enriched among the DAPs in DK517 induced by ABA, while these pathways were absent in ZD1002. Twenty-four and fifteen overlapping DAPs showed contrasting responses in the two maize genotypes after ABA treatment. Notably, the expression levels of six known ABA signaling genes, including SnRK2 and DRE-like proteins, were downregulated in DK517 but remained unaltered in ZD1002 following ABA application. These findings underscore the distinct effects of exogenous ABA on the grain-filling characteristics of different maize genotypes, emphasizing the importance of the hormone metabolic process in regulating kernel water content induced by exogenous abscisic acid in maize.
Three new monoterpenoid coumarins, zantholin A (3), altissimacoumarin P-Q (5, 6), two new monoterpenoid phenylpropanoids, altissmaphenylpropanoids A-B (2, 4), along with two known compounds (7, 8), were obtained from aqueous EtOH extracts of the root bark of Ailanthus altissima.
Objective: Parry-Romberg syndrome (PRS) is an acquired disease characterized by progressive unilateral atrophy of the facial skin, subcutaneous tissue, muscle, and bone. There are various hypotheses to try to explain the occurrence of the disease, but the specific etiology and pathogenesis remain unclear. This study aimed to explore the potential molecular pathogenesis of the disease by using next-generation RNA-sequencing technology. Methods: The authors collected oral mucosal tissue from the affected side and the healthy side from 3 patients with PRS. Tissue samples were subjected to RNA extraction, whole transcriptome sequencing, and bioinformatics analysis. Differentially expressed genes were obtained from both groups of samples and then analyzed for functional enrichment. Results: A total of 186 differentially expressed genes were screened from the 2 groups of samples. Compared with the healthy side, several immune-related genes, including immunoglobulin kappa variable (IGKV)2D-28, IGKV1D-33, IGKV1-33, and NLRP10, were significantly upregulated in the affected tissue. In addition, the differential genes were significantly enriched in metabolic pathways including pancreatic secretion, protein and fat digestion, and absorption. Conclusions: The authors described the gene expression differences between the affected and healthy tissues of patients with PRS for the first time. Immune responses may play a role in the pathogenesis of PRS.
A phytochemical study on the methanol extracts from the seeds of Peganum harmala L. led to a new quizonaline alkaloid (S)-vasicinone-1-O-β-d-glucopyranoside (1) and four known ones, (R)-vasicinone-1-O-β-d-glucopyranoside (2), (S)-vasicinone (3), vasicine (4), and deoxyvasicinone (5). Their structures were elucidated by spectroscopic analysis including IR, HR-ESI-MS, 1D and 2D NMR, and specific rotation as well as by comparison of the data with those in the literature. All of the alkaloids were screened for antiproliferative activity against human gastric cancer cells MCG-803 with MTT method. Compounds 1 and 3 exhibited moderate inhibitory activity.