The growth-inhibitory effects of pawpaw (Asimina triloba [L.] Dunal) roots,twigs, leaves,and fruit against human gastric (AGS) and cervical (HeLa) cancer cells and their anti-inflammatory activities

Molecular Biology Reports - The pawpaw tree has several beneficial effects. However, no studies have been conducted to address the mechanisms underlying the cytotoxic effects of pawpaw extracts...     

黄河三角洲滨海湿地微生物多样性及其驱动因子

微生物在湿地的生物地球化学循环和生态功能调节中发挥着重要作用,对全球气候变化具有重大影响,对维持全球生态系统的健康至关重要。以黄河三角洲滨海湿地为研究对象,通过采集代表性植被群落的土壤表层和部分植物根系,探究土壤微生物群落组成、根际微生物、环境因子及其内在的关联性和影响机制。研究结果表明不同植被覆盖地区微生物多样性存在差异,芦苇区和柽柳区微生物丰度高于泥滩区、碱蓬区和棉田,海漫滩微生物丰度高于河漫滩地和泥滩。土壤微生物菌群结构和多样性显著高于根际：土壤细菌的香农指数约为4-5.5,根际微生物的香农指数约为0-4。土壤细菌主要为厚壁菌门、变形菌门、拟杆菌门和放线菌门,占样品总数的90%以上;而根际细菌主要是蓝藻门、变形菌门和放线菌门,二者在属水平上的菌群结构差异更加明显。环境因子的含量与生境类型有关,SO₄^2-和NO₃^-的相关性最高,植被覆盖区土壤中Mn⁴⁺、Fe³⁺和水解氮的含量低于滩涂裸地。冗余分析（RDA）表明,pH值在小空间尺度上对湿地土壤中细菌群落的影响较小,环境因子在门和属水平的解释率分别为89.7%和86.8%,其中K（23.4%）、NO₂^-（11.8%）、Mn⁴⁺（9.8%）和Na（8.0%）是解释门水平微生物区系结构变化和组成的主要因子。研究为理解湿地微生物多样性与湿地生态系统功能之间的影响机制提供了一个生态学视角,有助于了解黄河三角洲滨海湿地土壤和植物根际的细菌分布特征,对黄河三角洲退化滨海湿地的生物修复具有重要的指导意义。     

Ghrelin Affects Gastric Cancer Progression by Activating AMPK Signaling Pathway

Biochemical Genetics - As the endogenous ligand for the GH secretagogue receptor (GHSR), Ghrelin is aberrant expressed in multiple malignant carcinoma, and involved in regulating a number of...     

Drought stress and plant ecotype drive microbiome recruitment in switchgrass rhizosheath

The rhizosheath, a layer of soil grains that adheres firmly to roots, is beneficial for plant growth and adaptation to drought environments. Switchgrass is a perennial C4 grass which can form contact rhizosheath under drought conditions. In this study, we characterized the microbiomes of four different rhizocompartments of two switchgrass ecotypes (Alamo and Kanlow) grown under drought or well-watered conditions via 16S ribosomal RNA amplicon sequencing. These four rhizocompartments, the bulk soil, rhizosheath soil, rhizoplane, and root endosphere, harbored both distinct and overlapping microbial communities. The root compartments (rhizoplane and root endosphere) displayed low-complexity communities dominated by Proteobacteria and Firmicutes. Compared to bulk soil, Cyanobacteria and Bacteroidetes were selectively enriched, while Proteobacteria and Firmicutes were selectively depleted, in rhizosheath soil. Taxa from Proteobacteria or Firmicutes were specifically selected in Alamo or Kanlow rhizosheath soil. Following drought stress, Citrobacter and Acinetobacter were further enriched in rhizosheath soil, suggesting that rhizosheath microbiome assembly is driven by drought stress. Additionally, the ecotype-specific recruitment of rhizosheath microbiome reveals their differences in drought stress responses. Collectively, these results shed light on rhizosheath microbiome recruitment in switchgrass and lay the foundation for the improvement of drought tolerance in switchgrass by regulating the rhizosheath microbiome.     

Curvature-Dependent Cavity-Nanoparticle Scaffold-Based Clusters with LSPR Enhancement as SERS Substrates

Plasmonics - Tunable local surface plasmon resonance (LSPR) enhancement properties of cavity-nanoparticle scaffold-based clusters were investigated via finite-difference time-domain (FDTD)...     

Kip-related protein 3 is required for control of endoreduplication in the shoot apical meristem and leaves of Arabidopsis

The cell cycle plays an important role in the development and adaptation of multicellular organisms; specifically, it allows them to optimally adjust their architecture in response to environmental changes. Kip-related proteins (KRPs) are important negative regulators of cyclin-dependent kinases (CDKs), which positively control the cell cycle during plant development. The Arabidopsis genome possesses seven KRP genes with low sequence similarity and distinct expression patterns; however, why Arabidopsis needs seven KRP genes and how these genes function in cell cycle regulation are unknown. Here, we focused on the characterization of KRP3, which was found to have unique functions in the shoot apical meristem (SAM) and leaves. KRP3 protein was localized to the SAM, including the ground meristem and vascular tissues in the ground part of the SAM and cotyledons. In addition, KRP3 protein was stabilized when treated with MG132, an inhibitor of the 26S proteasome, indicating that the protein may be regulated by 26S proteasome-mediated protein degradation. KRP3-overexpressing (KRP3 OE) transgenic plants showed reduced organ size, serrated leaves, and reduced fertility. Interestingly, the KRP3 OE transgenic plants showed a significant reduction in the size of the SAM with alterations in cell arrangement. In addition, compared to the wild type, the KRP3 OE transgenic plants had a higher DNA ploidy level in the SAM and leaves. Taken together, our data suggest that KRP3 plays important regulatory roles in the cell cycle and endoreduplication in the SAM and leaves.     

Sphingosine and FTY720 modulate pacemaking activity in interstitial cells of Cajal from mouse small intestine

Interstitial cells of Cajal (ICCs) are the pacemakers of the gastrointestinal tract, and transient receptor potential melastatin type 7 (TRPM7) and Ca²⁺ activated Cl⁻ channels (ANO1) are candidate the generators of pacemaker potentials in ICCs. The effects of D-erythro-sphingosine (SPH) and structural analogues of SPH, that is, N,N-dimethyl-Derythro-sphingosine (N,N-DMS), FTY720, and FTY720-P on the pacemaking activities of ICCs were examined using the whole cell patch clamp technique. SPH, N,N-DMS, and FTY720 decreased the amplitudes of pacemaker potentials in ICC clusters, but resting membrane potentials displayed little change. Also, perfusing SPH, N,N-DMS, or FTY720 in the bath reduced both inward and outward TRPM7-like currents in single ICCs, and inhibited ANO1 currents. The another structural analogue of SPH, FTY720-P was ineffective at the pacemaker potentials in ICC clusters and the TRPM7-like currents in single ICCs. Furthermore, FTY720- P had no effect on ANO1. These results suggest that SPH, N,N-DMS, and FTY720 modulate the pacemaker activities of ICCs, and that TRPM7 and ANO1 channels affect intestinal motility.     

The protein kinase 2 inhibitor CX-4945 regulates osteoclast and osteoblast differentiation In vitro

Drug repositioning can identify new therapeutic applications for existing drugs, thus mitigating high R&D costs. The Protein kinase 2 (CK2) inhibitor CX-4945 regulates human cancer cell survival and angiogenesis. Here we found that CX-4945 significantly inhibited the RANKL-induced osteoclast differentiation, but enhanced the BMP2-induced osteoblast differentiation in a cell culture model. CX-4945 inhibited the RANKL-induced activation of TRAP and NFATc1 expression accompanied with suppression of Akt phosphorylation, but, in contrast, it enhanced the BMP2-mediated ALP induction and MAPK ERK1/2 phosphorylation. CX-4945 is thus a novel drug candidate for bone-related disorders such as osteoporosis.     

Proangiogenic TIE2+/CD31+ macrophages are the predominant population of tumor-associated macrophages infiltrating metastatic lymph nodes

Tumor-associated macrophages (TAMs) accumulate in various cancers and promote tumor angiogenesis and metastasis, and thus may be ideal targets for the clinical diagnosis of tumor metastasis with high specificity. However, there are few specific markers to distinguish between TAMs and normal or inflammatory macrophages. Here, we show that TAMs localize in green fluorescent protein-labeled tumors of metastatic lymph nodes (MLNs) from B16F1 melanoma cells but not in necrotic tumor regions, suggesting that TAMs may promote the growth of tumor cells and the progression of tumor metastasis. Furthermore, we isolated pure populations of TAMs from MLNs and characterized their gene expression signatures compared to peritoneal macrophages (PMs), and found that TAMs significantly overexpress immunosuppressive cytokines such as IL-4, IL-10, and TGF-β as well as proangiogenic factors such as VEGF, TIE2, and CD31. Notably, immunological analysis revealed that TIE2⁺/CD31⁺ macrophages constitute the predominant population of TAMs that infiltrate MLNs, distinct from tissue or inflammatory macrophages. Importantly, these TIE2⁺/CD31⁺ macrophages also heavily infiltrated MLNs from human breast cancer biopsies but not reactive hyperplastic LNs. Thus, TIE2⁺/CD31⁺ macrophages may be a unique histopathological biomarker for detecting metastasis in clinical diagnosis, and a novel and promising target for TAM-specific cancer therapy.