Metabolic reprogramming in astrocytes results in neuronal dysfunction in intellectual disability.

Astrocyte aerobic glycolysis provides vital trophic support for central nervous system neurons. However, whether and how astrocytic metabolic dysregulation contributes to neuronal dysfunction in intellectual disability (ID) remain unclear. Here, we demonstrate a causal role for an ID-associated SNX27 mutation (R198W) in cognitive deficits involving reshaping astrocytic metabolism. We generated SNX27R196W (equivalent to human R198W) knock-in mice and found that they displayed deficits in synaptic function and learning behaviors. SNX27R196W resulted in attenuated astrocytic glucose uptake via GLUT1, leading to reduced lactate production and a switch from homeostatic to reactive astrocytes. Importantly, lactate supplementation or a ketogenic diet restored neuronal oxidative phosphorylation and reversed cognitive deficits in SNX27R196W mice. In summary, we illustrate a key role for astrocytic SNX27 in maintaining glucose supply and glycolysis and reveal that altered astrocytic metabolism disrupts the astrocyte-neuron interaction, which contributes to ID. Our work also suggests a feasible strategy for treating ID by restoring astrocytic metabolic function.

SCASP: A Simple and Robust SDS-Aided Sample Preparation Method for Proteomic Research.

SDS is widely used in sample preparation for proteomic research. However, SDS is incompatible with LC and electrospray ionization. SDS depletion is therefore required ahead of LC-MS analysis. Most of current SDS removal strategies are time consuming, laborious, and have low reproducibility. Here, we describe a method, SDS-cyclodextrin (CD)-assisted sample preparation, by which CD can bind to SDS and form CD-SDS complexes in solutions, allowing for direct tryptic digestion. We demonstrate that SDS-CD-assisted sample preparation is a simple, fast, and robust SDS-based sample preparation method for proteomics application.

Comprehensive identification and expression analysis of CRY gene family in Gossypium.

BACKGROUND: The cryptochromes (CRY) are specific blue light receptors of plants and animals, which play crucial roles in physiological processes of plant growth, development, and stress tolerance. RESULTS: In the present work, a systematic analysis of the CRY gene family was performed on twelve cotton species, resulting in 18, 17, 17, 17, and 17 CRYs identified in five alloteraploid cottons (Gossypium hirsutum, G. barbadense, G. tomentosum, G. mustelinum and G. darwinii), respectively, and five to nine CRY genes in the seven diploid species. Phylogenetic analysis of protein-coding sequences revealed that CRY genes from cottons and Arabidopsis thaliana could be classified into seven clades. Synteny analysis suggested that the homoeolog of G. hirsutum Gh_A02G0384 has undergone an evolutionary loss event in the other four allotetraploid cotton species. Cis-element analysis predicated the possible functions of CRY genes in G. hirsutum. RNA-seq data revealed that Gh_D09G2225, Gh_A09G2012 and Gh_A11G1040 had high expressions in fiber cells of different developmental states. In addition, the expression levels of one (Gh_A03G0120), 15 and nine GhCRY genes were down-regulated following the PEG, NaCl and high-temperature treatments, respectively. For the low-temperature treatment, five GhCRY genes were induced, and five were repressed. These results indicated that most GhCRY genes negatively regulate the abiotic stress treatments. CONCLUSION: We report the structures, domains, divergence, synteny, and cis-elements analyses systematically of G. hirsutum CRY genes. Possible biological functions of GhCRY genes in differential tissues as well as in response to abiotic stress during the cotton plant life cycle were predicted.

Leber's hereditary optic neuropathy plus dystonia caused by the mitochondrial ND1 gene m.4160 T > C mutation.

BACKGROUND: Leber's hereditary optic neuropathy (LHON) is a common mitochondrial disease. More than 30 variants in the mitochondrial DNA (mtDNA) have been previously described in LHON. However, the pathogenicity of some variants remains unclear. Herein, we report a 19-year-old boy presenting unique LHON plus dystonia syndrome with the rare m.4136A > G and m.4160 T > C variants and elucidate the molecular pathomechanisms of the m.4160 T > C mutation. METHODS: We performed clinical, molecular genetic analysis, and biochemical investigation in the patient's different tissues and cybrid cell lines. RESULTS: The optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) of the patient showed typical pathological changes-a significant decrease in the 17 thickness of the retinal nerve fiber layer (RNFL) and the ganglion cell complex (GCC). Brain magnetic resonance imaging (MRI) found noteworthy abnormal signals in the basal ganglia region. The genetic analysis revealed that the m.4160 T > C variant was heteroplasmic in the blood (80.2%), urine sediment (90.8%), and oral mucosal (81.7%) samples of the patient. In contrast, the m.4136A > G variant was homoplasmic in all available tissues. Biochemical and bioenergetic investigations showed decreased mitochondrial protein levels and mitochondrial respiration deficiency in cybrid cells harboring these variants. CONCLUSIONS: This research provided more comprehensive data to help gain insight into the pathogenicity of the m.4160 T > C variant and broaden our view on the LHON plus phenotype.

Profiling biotoxicities of hexafluoropropylene oxide trimer acid with human embryonic stem cell-based assays.

Hexafluoropropylene oxide trimer acid (HFPO-TA), an emerging replacement of perfluorooctanoic acid (PFOA), has recently been reported to be a potential environmental contaminant. Due to the similar structure to PFOA, HFPO-TA may cause comparable adverse effects on human health. Therefore, evaluating the toxic profiles of HFPO-TA has become an urgent task. In this study, we investigated the cytotoxicity and hepatoxicity of HFPO-TA using human embryonic stem cell (hESC)-based assays. Results showed that HFPO-TA reduced hESCs' viability in a dose dependent manner, and the calculated IC50 for 24, 48 and 72 hr were 222.8, 167.4, and 80.6 µmol/L, respectively. Significant intracellular ROS accumulation and mitochondrion membrane potential reduction were detected with HFPO-TA exposure, and increased apoptotic/necrotic cells were also observed in high dose of HFPO-TA treated group. Moreover, HFPO-TA at noncytotoxic concentrations also significantly impaired the functions of induced hepatocytes by diminishing cell glycogen storage ability and deregulating specific functional genes. Transcriptome sequencing analysis identified a set of hepatic associated biological processes responding to HFPO-TA exposure. PPAR was the most significantly enriched pathway. Genes including FGA, FGB, FGG, AHSG, HRG, ITIH2, ALB were characterized as hub genes by cytoHubba plug-in. These data indicated that HFPO-TA is a potential hepatotoxicant, and may not be a safe replacement for PFOA.

Characterization of cotton ARF factors and the role of GhARF2b in fiber development.

BACKGROUND: Cotton fiber is a model system for studying plant cell development. At present, the functions of many transcription factors in cotton fiber development have been elucidated, however, the roles of auxin response factor (ARF) genes in cotton fiber development need be further explored. RESULTS: Here, we identify auxin response factor (ARF) genes in three cotton species: the tetraploid upland cotton G. hirsutum, which has 73 ARF genes, and its putative extent parental diploids G. arboreum and G. raimondii, which have 36 and 35 ARFs, respectively. Ka and Ks analyses revealed that in G. hirsutum ARF genes have undergone asymmetric evolution in the two subgenomes. The cotton ARFs can be classified into four phylogenetic clades and are actively expressed in young tissues. We demonstrate that GhARF2b, a homolog of the Arabidopsis AtARF2, was preferentially expressed in developing ovules and fibers. Overexpression of GhARF2b by a fiber specific promoter inhibited fiber cell elongation but promoted initiation and, conversely, its downregulation by RNAi resulted in fewer but longer fiber. We show that GhARF2b directly interacts with GhHOX3 and represses the transcriptional activity of GhHOX3 on target genes. CONCLUSION: Our results uncover an important role of the ARF factor in modulating cotton fiber development at the early stage.

Different classes of small RNAs are essential for head regeneration in the planarian Dugesia japonica.

BACKGROUND: Planarians reliably regenerate all body parts after injury, including a fully functional head and central nervous system. But until now, the expression dynamics and functional role of miRNAs and other small RNAs during the process of head regeneration are not well understood. Furthermore, little is known about the evolutionary conservation of the relevant small RNAs pathways, rendering it difficult to assess whether insights from planarians will apply to other taxa. RESULTS: In this study, we applied high throughput sequencing to identify miRNAs, tRNA fragments and piRNAs that are dynamically expressed during head regeneration in Dugesia japonica. We further show that knockdown of selected small RNAs, including three novel Dugesia-specific miRNAs, during head regeneration induces severe defects including abnormally small-sized eyes, cyclopia and complete absence of eyes. CONCLUSIONS: Our findings suggest that a complex pool of small RNAs takes part in the process of head regeneration in Dugesia japonica and provide novel insights into global small RNA expression profiles and expression changes in response to head amputation. Our study reveals the evolutionary conserved role of miR-124 and brings further promising candidate small RNAs into play that might unveil new avenues for inducing restorative programs in non-regenerative organisms via small RNA mimics based therapies.

Genome-wide characterization of the GRF family and their roles in response to salt stress in Gossypium.

BACKGROUND: Cotton (Gossypium spp.) is the most important world-wide fiber crop but salt stress limits cotton production in coastal and other areas. Growth regulation factors (GRFs) play regulatory roles in response to salt stress, but their roles have not been studied in cotton under salt stress. RESULTS: We identified 19 GRF genes in G. raimondii, 18 in G. arboreum, 34 in G. hirsutum and 45 in G. barbadense, respectively. These GRF genes were phylogenetically analyzed leading to the recognition of seven GRF clades. GRF genes from diploid cottons (G. raimondii and G. arboreum) were largely retained in allopolyploid cotton, with subsequent gene expansion in G. barbadense relative to G. hirsutum. Most G. hirsutum GRF (GhGRF) genes are preferentially expressed in young and growing tissues. To explore their possible role in salt stress, we used qRT-PCR to study expression responses to NaCl treatment, showing that five GhGRF genes were down-regulated in leaves. RNA-seq experiments showed that seven GhGRF genes exhibited decreased expression in leaves under NaCl treatment, three of which (GhGRF3, GhGRF4, and GhGRF16) were identified by both RNA-seq and qRT-PCR. We also identified six and three GRF genes that exhibit decreased expression under salt stress in G. arboreum and G. barbadense, respectively. Consistent with its lack of leaf withering or yellowing under the salt treatment conditions, G. arboreum had better salt tolerance than G. hirsutum and G. barbadense. Our results suggest that GRF genes are involved in salt stress responses in Gossypium. CONCLUSION: In summary, we identified candidate GRF genes that were involved in salt stress responses in cotton.

Influence of Scapula Training Exercises on Shoulder Joint Function After Surgery for Rotator Cuff Injury.

BACKGROUND The aim of this study was to assess the clinical effectiveness of scapula training exercises on shoulder function after surgery for rotator cuff injury. MATERIAL AND METHODS Forty-six patients with rotator cuff injury after surgery were randomized into the experiment group or control group. Both groups were treated with conventional therapeutic exercise and physical therapy, and scapular training exercise was added to the experiment group. Patient status was evaluated by Constant-Murley scale (CMS), visual analogue scale (VAS), and the active range of motion (ROM) of the shoulder before and after 6 weeks and 12 weeks of treatment. RESULTS After 6 weeks and 12 weeks of treatment, all evaluations of the 2 groups were significantly improved as compared with those before treatment (P0.05). After 12 weeks of treatment, all items in the experimental group were significantly improved compared to the control group (P<0.05). CONCLUSIONS The combination of conventional rehabilitation interventions and scapular training exercise were an effective treatment of the shoulder dysfunction. Moreover, increased Scapula training exercise had better effect on the improvement of shoulder function.

Genetic substructure and admixture of Mongolians and Kazakhs inferred from genome-wide array genotyping.

BACKGROUND: Mongolian populations are widely distributed geographically, showing abundant ethnic diversity with geographic and tribal differences. AIM: To infer the genetic substructure, admixture and ancient genetic sources of Mongolians together with Kazakhs. SUBJECTS AND METHODS: We genotyped more than 690,000 genome-wide SNPs from 33 Mongolian and Chinese Kazakh individuals and compared these with both ancient and present-day Eurasian populations using Principal Component Analysis (PCA), ADMIXTURE, Refine-IBD, f statistics, qpWave and qpAdm. RESULTS: We found genetic substructures within Mongolians corresponding to Ölöd, Chahar, and Inner Mongolian clusters, which was consistent with tribe classifications. Mongolian and Kazakh groups derived about 6-40% of West Eurasian related ancestry, most likely from Bronze Age Steppe populations. The East Asian related ancestry in Mongolian and Kazakh groups was well represented by the Neolithic DevilsCave related nomadic lineage, comprising 42-64% of studied groups. We also detected 10-51% of Han Chinese related ancestry in Mongolian and Kazakh groups, especially in Inner Mongolians. The average admixture times for Inner Mongolian, Mongolian_Chahar, Mongolian_Ölöd and Chinese Kazakh were about 1381, 626, 635 and 632 years ago, respectively, with Han and French as the sources. CONCLUSION: The DevilsCave related ancestry was once widespread westwards covering a wide geographical range from Far East Russia to the Mongolia Plateau. The formation of present-day Mongolic and Turkic-speaking populations has also received genetic influence from agricultural expansion.

Erbin plays a critical role in human umbilical vein endothelial cell migration and tubular structure formation via the Smad1/5 pathway.

Angiogenesis is an important process in atherosclerosis. ErbB2 was proved to have an important role in vascular development, but it is still unclear whether Erbin expresses in vessels as well as its location and function in the vessels. In the current study, we investigated the location and function of Erbin in human umbilical veins. The human umbilical veins were prepared, and immunofluorescent analysis was performed to determine the expression of Erbin. Human umbilical vein endothelial cells (HUVECs) were cultured and the lentivirus (LV) containing Erbin RNAi was also prepared. After transfection with the lentivirus, CCK-8 assay and Annexin V-PI assay were used for cell proliferation and apoptosis, respectively. Cell migration was studied using the scratch wound healing assay and the transwell assay. The capillary-like tube formation assay was performed to illustrate the effect of Erbin on HUVEC tube formation. Expression of signaling pathway molecules was assessed with Western blot. The immunofluorescent analysis suggested that Erbin expressed in human umbilical veins and the majority of the Erbin is strongly colocalized in endothelial cells. Although knockdown of Erbin did not affect HUVEC proliferation and apoptosis, it significantly suppressed HUVEC migration and tubular structure formation. Erbin knockdown showed no effect on the ERK1/2 and Smad2/3 signaling pathways but significantly promoted Smad1/5 phosphorylation and nuclear translocation. Ablation of the Smad1/5 pathway decreased the effects of Erbin on endothelial cells. Erbin is mainly localized in endothelial cells in human umbilical veins and plays a critical role in endothelial cell migration and tubular formation via the Smad1/5 pathway.

Establishment of a bead-based duplex assay for the simultaneous quantitative detection of Neuropilin-1 and Neuropilin-2 using xMAP technology and its clinical application.

BACKGROUND: Neuropilins (Nrps) are a new type of broad-spectrum tumor marker. Currently, a method for accurate simultaneous quantification of Nrps is not available. We aimed to develop a bead-based and duplexed flow cytometric assay that could be used for accurate and simultaneous quantification of Nrp1 and Nrp2 for scientific research or clinical diagnosis. METHODS: We coupled anti-human Nrp1-11# mAb and anti-human Nrp2-C3 mAb to magnetic beads 18# and 25#, respectively. Capturing antibodies and detecting antibodies were then combined to detect Nrps by a bead-based Luminex assay, which was subsequently applied to quantify Nrps in clinical serum samples. RESULTS: The results showed that the detection value of Nrps ranged from 10 to 100 000 pg/mL for Nrp1 and from 25 to 100 000 pg/mL for Nrp2. The detection sensitivity reached 10 pg/mL for Nrp1 and 24.8 pg/mL for Nrp2. Intra-assay variances ranged from 1.0% to 2.6% for Nrp1 and from 2.9% to 4.0% for Nrp2, and interassay variances ranged from 1.5% to 6.4% for Nrp1 and from 4.2% to 8.1% for Nrp2. The Nrp1 and Nrp2 recoveries were 96.6%-103.6% and 95.6%-102.3%, respectively. Irrelevant antigens had no interference in the paired-detection system, and the mean fluorescence intensity (MFI) values were stable for months. CONCLUSION: A bead-based, duplexed flow cytometric assay (xMAP® technology) was developed to detect Nrp1 and Nrp2. The assay provided rapid, high-throughput results and was much more sensitive, specific, reproducible, and stable than existing assays. In addition, this assay could be applied in early-stage cancer screening, tumor malignancy analysis, and prognosis assessment.

Mitochondria-Targeting Small Molecules Effectively Prevent Cardiotoxicity Induced by Doxorubicin.

Doxorubicin (Dox) is a chemotherapeutic agent widely used for the treatment of numerous cancers. However, the clinical use of Dox is limited by its unwanted cardiotoxicity. Mitochondrial dysfunction has been associated with Dox-induced cardiotoxicity. To mitigate Dox-related cardiotoxicity, considerable successful examples of a variety of small molecules that target mitochondria to modulate Dox-induced cardiotoxicity have appeared in recent years. Here, we review the related literatures and discuss the evidence showing that mitochondria-targeting small molecules are promising cardioprotective agents against Dox-induced cardiac events.

Ratiometric Visualization of NO/H2S Cross-Talk in Living Cells and Tissues Using a Nitroxyl-Responsive Two-Photon Fluorescence Probe.

It is of scientific significance to explore the intricate relationship between two crucial gasotransmitters nitric oxide (NO) and hydrogen sulfide (H2S) because they exert similar and interdependent biological actions within the living organisms. Nevertheless, visualization of the NO/H2S crosstalk using effective molecular imaging tools remains challenging. To address this issue, and given that nitroxyl (HNO) has been implicated as the interdependent production of NO and H2S via a network of cascading chemical reactions, we herein design a ratiometric two-photon fluorescent probe for HNO, termed TP-Rho-HNO, which consists of benzo[h]chromene-rhodol scaffold as two-photon energy transfer cassette with phosphine moiety as specific HNO recognition unit. The newly proposed probe has been successfully applied in ratiometric two-photon bioimaging of endogenous HNO derived from NO and H2S interaction in the human umbilical vein cells (HUVECs) and as well as in rat brain tissues. Intriguingly, the imaging results consistently demonstrate that the mutually dependent upgeneration of H2S and NO are present in living biosystems, indicating that this molecular probe would provide a powerful approach to elucidate the chemical foundation for the anfractuous cross-talk between the NO and H2S signaling pathways in biology.

MicroRNA-196b Inhibits Cell Growth and Metastasis of Lung Cancer Cells by Targeting Runx2.

BACKGROUND/AIMS: Lung cancer is one of the most common causes of cancer related deaths worldwide. The role of several microRNAs (miRNAs) including miR-196b in different cancers has already been established. The study was aimed to explore the role of miR-196b in lung cancer and its possible underlying mechanism. METHODS: Human lung cancer cell line A549 was transfected with miR-196b mimic, miR-196b inhibitor and corresponding controls. Then cell viability, migration, invasion, and apoptosis of A549 lung cancer cells either with overexpression or with suppression of miR-196b were estimated sequentially. Next, dual luciferase activity assay was performed to clarify whether Runx2 was a direct target of miR-196b. Finally, the expressions of main factors associated with epithelial mesenchymal transition (EMT), PI3K/AKT/GSK3ß, Smad, and JNK pathways were detected by western blot. RESULTS: MiR-196b expression was significantly decreased in A549, H1650 and H1299 cell lines compared with in WI-38 and HEL-1 cell lines. Overexpression of miR-196b suppressed cell viability, migration, invasion, and induced apoptosis as well as inhibited TGF-ß induced EMT process in A549 cells. In addition, Runx2 was a putative target of miR-196b, and Runx2 silence remarkably increased cell apoptosis and abolished the promotive effects of miR-196b suppression on cell viability, migration and invasion. Finally, miR-196b also mediated its action by inactivation of PI3K/AKT/GSK3ß, Smad, and JNK pathways by down-regulation of Runx2. CONCLUSION: MiR-196b functions as a tumor suppressor that inhibited cell growth and metastasis of lung cancer cells by targeting Runx2. These findings provided further evidences for treatment of lung cancer.

Bioactive Bafilomycins and a New N-Arylpyrazinone Derivative from Marine-derived Streptomyces sp. HZP-2216E.

A MeOH extract prepared from culture of an actinomycete Streptomyces sp. HZP-2216E isolated from marine green algae Ulva pertusa was found to significantly inhibit proliferation of human glioma cells. Two different media were applied to culture this marine actinomycete, which produced two new compounds of 23-O-butyrylbafilomycin D and streptoarylpyrazinone A, together with known bafilomycin D, 9-hydroxybafilomycin D, and bafilomycin A1. Structures of new compounds were determined by extensive NMR spectroscopic analyses and HRESIMS data. Bioactive assay indicated that all isolated bafilomycins significantly inhibited the proliferation of different glioma cell lines and the growth of methicillin-resistant Staphylococcus aureus with 23-O-butyrylbafilomycin D as the most active compound. Streptoarylpyrazinone A is a new N-arylpyrazinone derivative existing as a zwitterion, and this type of compounds was rarely found from natural resources.

miR-218 suppressed the growth of lung carcinoma by reducing MEF2D expression.

Lung carcinoma is a deadly malignant disease with poor prognosis and increasing incidence in recent years. However, the molecular mechanism underlying the initiation and progression of lung cancer is still not completely elucidated. Recently, myocyte enhancer factor 2D (MEF2D) has been reported to promote the growth of liver cancer, but its implication in lung cancer is still unknown. This study is aimed to determine the role of MEF2D in lung carcinoma. Quantitative PCR (qPCR) and immunoblot assays showed that MEF2D was overexpressed in lung cancer tissues and cell lines, compared with the matched normal tissues and cell lines. Small interfering RNA (siRNA) suppression of MEF2D was able to reduce the proliferation, survival, and invasion of lung carcinoma cells. The transfection of MEF2D-expressing constructs into normal lung fibroblast cells promoted their proliferation and motility. The role of MEF2D in the growth of lung cancer was also confirmed in mice. Further study revealed that miR-218, which was underexpressed in lung carcinoma, was predicted to bind the 3'-untranslated region (UTR) of MEF2D mRNA. miR-218 was shown to suppress the activity of luciferase with MEF2D 3'-UTR. The changes in miR-218 levels affected the expression of MEF2D in lung cancer cells and normal fibroblast cells. There is also an inverse association between miR-218 abundance and MEF2D levels in the lung carcinoma specimen. Furthermore, the transfection of a plasmid that expressed MEF2D resistance to miR-218 regulation abolished the inhibitory effect of miR-218 on lung cancer cells. Collectively, MEF2D overexpression participated in the growth of lung cancers and its aberrant expression may result from the reduction of tumor suppressor miR-218.

Hydrogenated Bismuth Molybdate Nanoframe for Efficient Sunlight-Driven Nitrogen Fixation from Air.

Sunlight-driven dinitrogen fixation can lead to a novel concept for the production of ammonia under mild conditions. However, the efficient artificial photosynthesis of ammonia from ordinary air (instead of high pure N2 ) has never been implemented. Here, we report for the first time the intrinsic catalytic activity of Bi2 MoO6 catalyst for direct ammonia synthesis under light irradiation. The edge-exposed coordinatively unsaturated Mo atoms in an Mo-O coordination polyhedron can act as activation centers to achieve the chemisorption, activation, and photoreduction of dinitrogen efficiently. Using that insight as a starting point, through rational structure and defect engineering, the optimized Bi2 MoO6 sunlight-driven nitrogen fixation system, which simultaneously possesses robust nitrogen activation ability, excellent light-harvesting performance, and efficient charge transmission was successfully constructed. As a surprising achievement, this photocatalytic system demonstrated for the first time ultra-efficient (1.3 mmol g-1 h-1 ) and stable sunlight-driven nitrogen fixation from air in the absence of any organic scavengers.

Functional characterization of a basic helix-loop-helix (bHLH) transcription factor GhDEL65 from cotton (Gossypium hirsutum).

Cotton fiber is proposed to share some similarity with the Arabidopsis thaliana leaf trichome, which is regulated by the MYB-bHLH-WD40 transcription complex. Although several MYB transcription factors and WD40 family proteins in cotton have been characterized, little is known about the role of bHLH family proteins in cotton. Here, we report that GhDEL65, a bHLH protein from cotton (Gossypium hirsutum), is a functional homologue of Arabidopsis GLABRA3 (GL3) and ENHANCER OF GLABRA3 (EGL3) in regulating trichome development. Transcripts of GhDEL65 were detected in 0 ∼ 1 days post-anthesis (DPA) ovules and abundant in 3-DPA fibers, implying that GhDEL65 may act in early fiber development. Ectopic expression of GhDEL65 in Arabidopsis gl3 egl3 double mutant partly rescued the trichome development, and constitutive expression of GhDEL65 in wild-type plants led to increased trichome density on rosette leaves and stems, mainly by activating the transcription of two key positive regulators of trichome development, GLABRA1 (GL1) and GLABRA2 (GL2), and suppressed the expression of a R3 single-repeat MYB factor TRIPTYCHON (TRY). GhDEL65 could interact with cotton R2R3 MYB transcription factors GhMYB2 and GhMYB3, as well as the WD40 protein GhTTG3, suggesting that the MYB-bHLH-WD40 protein complex also exists in cotton fiber cell, though its function in cotton fiber development awaits further investigation.

New Metabolites and Bioactive Actinomycins from Marine-Derived Streptomyces sp. ZZ338.

An extract prepared from the culture of a marine-derived actinomycete Streptomyces sp. ZZ338 was found to have significant antimicrobial and antiproliferative activities. A chemical investigation of this active extract resulted in the isolation of three known bioactive actinomycins (1-3) and two new metabolites (4 and 5). The structures of the isolated compounds were identified as actinomycins D (1), V (2), X0ß (3), 2-acetylamino-3-hydroxyl-4-methyl-benzoic acid methyl ester (4), and N-1S-(4-methylaminophenylmethyl)-2-oxo-propyl acetamide (5) based on their nuclear magnetic resonance (NMR) and high resolution electrospray ionization mass spectroscopy (HRESIMS) data as well as their optical rotation. This class of new compound 5 had never before been found from a natural resource. Three known actinomycins showed activities in inhibiting the proliferation of glioma cells and the growth of methicillin-resistant Staphylococcus aureus, Escherichia coli, and Candida albicans and are responsible for the activity of the crude extract. Actinomycin D (1) was also found to downregulate several glioma metabolic enzymes of glycolysis, glutaminolysis, and lipogenesis, suggesting that targeting multiple tumor metabolic regulators might be a new anti-glioma mechanism of actinomycin D. This is the first report of such a possible mechanism for the class of actinomycins.