Title: Discovering metabolic vulnerability using spatially resolved metabolomics for antitumor small molecule-drug conjugates development as a precise cancer therapy strategy Wang X, Zhang J, Zheng K, Du Q, Wang G, Huang J, Zhou Y, Li Y, Jin H, He J Ref: J Pharm Anal, 13:776, 2023 : PubMed
Against tumor-dependent metabolic vulnerability is an attractive strategy for tumor-targeted therapy. However, metabolic inhibitors are limited by the drug resistance of cancerous cells due to their metabolic plasticity and heterogeneity. Herein, choline metabolism was discovered by spatially resolved metabolomics analysis as metabolic vulnerability which is highly active in different cancer types, and a choline-modified strategy for small molecule-drug conjugates (SMDCs) design was developed to fool tumor cells into indiscriminately taking in choline-modified chemotherapy drugs for targeted cancer therapy, instead of directly inhibiting choline metabolism. As a proof-of-concept, choline-modified SMDCs were designed, screened, and investigated for their druggability in vitro and in vivo. This strategy improved tumor targeting, preserved tumor inhibition and reduced toxicity of paclitaxel, through targeted drug delivery to tumor by highly expressed choline transporters, and site-specific release by carboxylesterase. This study expands the strategy of targeting metabolic vulnerability and provides new ideas of developing SMDCs for precise cancer therapy.
Title: Interrelationship between 2019-nCov receptor DPP4 and diabetes mellitus targets based on protein interaction network Gao Q, Zhang W, Li T, Yang G, Zhu W, Chen N, Jin H Ref: Sci Rep, 12:188, 2022 : PubMed
Patients with diabetes are more likely to be infected with Coronavirus disease 2019 (COVID-19), and the risk of death is significantly higher than ordinary patients. Dipeptidyl peptidase-4 (DPP4) is one of the functional receptor of human coronavirus. Exploring the relationship between diabetes mellitus targets and DPP4 is particularly important for the management of patients with diabetes and COVID-19. We intend to study the protein interaction through the protein interaction network in order to find a new clue for the management of patients with diabetes with COVID-19. Diabetes mellitus targets were obtained from GeneCards database. Targets with a relevance score exceeding 20 were included, and DPP4 protein was added manually. The initial protein interaction network was obtained through String. The targets directly related to DPP4 were selected as the final analysis targets. Importing them into String again to obtain the protein interaction network. Module identification, gene ontology (GO) analysis and Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis were carried out respectively. The impact of DPP4 on the whole network was analyzed by scoring the module where it located. 43 DPP4-related proteins were finally selected from the diabetes mellitus targets and three functional modules were found by the cluster analysis. Module 1 was involved in insulin secretion and glucagon signaling pathway, module 2 and module 3 were involved in signaling receptor binding. The scoring results showed that LEP and apoB in module 1 were the highest, and the scores of INS, IL6 and ALB of cross module associated proteins of module 1 were the highest. DPP4 is widely associated with key proteins in diabetes mellitus. COVID-19 may affect DPP4 in patients with diabetes mellitus, leading to high mortality of diabetes mellitus combined with COVID-19. DPP4 inhibitors and IL-6 antagonists can be considered to reduce the effect of COVID-19 infection on patients with diabetes.
ETHNOPHARMACOLOGICAL RELEVANCE: Silkworm (Bombyx mori) and Korean angelica (KoAg; Angelica gigas Nakai) have been widely used as traditional oriental medicines in Korea, China, and Japan to treat various diseases such as anemia, cold, diabetes, palsy, stroke, etc. Steamed and freeze-dried mature silkworm powder, also known as HongJam (HJ), and extracts of KoAg root (KoAgE) are currently sold in Korea as functional foods to improve memory, cognition, and liver functions. However, the molecular and pharmacological basis for the improvement of brain functions of HJ and KoAgE has not yet been elucidated. AIM OF STUDY: This study aimed to elucidate the molecular basis underlying the memory-enhancing effects of HJ and KoAgE and determine whether administration of HJ and KoAgE complexes (HJ + KoAgC) has additive memory and healthspan-enhancing effects. MATERIALS AND METHODS: The MCI mouse models generated by intraperitoneal injection of Scopolamine (Sco-IP) were orally administered with HJ and KoAgE alone or as complexes. Their memory-enhancing effects were examined on spatial, fear-aggravated, and social memories and compared with control or Donepezil (Dp) treatment. The activities of mitochondria complex (MitoCom) I-IV and acetylcholinesterase (AChE) and the amounts of ATP in the mouse brains were examined. The Drosophila model was used to investigate lifespan- and healthspan-promoting effects of HJ + KoAgC. RESULTS: Administration of HJ + KoAgC produced more memory-enhancing effects than administration of HJ or KoAgE alone or Dp. The increase in MitoCom I-IV activities and ATP amounts and the decrease in AChE activities in the mouse brains were the molecular basis for the memory enhancement. The greatest improvement in memory and mitochondrial function was observed when the mice were administered the 1:0.8 ratio of HJ + KoAgC. Administration of HJ + KoAgC to Drosophila prolonged the lifespan and the healthspan and increased the amounts of ATP. CONCLUSION: HJ + KoAgC had superior effects on memory improvement and healthspan extension by increasing mitochondrial activities and ATP amounts in treated animal models.
Alzheimer's disease (AD) is a neurodegenerative disorder with multiple pathological features. Therefore, a multitarget-directed ligands (MTDLs) strategy has been developed to treat AD. We have previously designed and synthesized dimeric tacrine(10)-hupyridone (A10E), a novel tacrine derivative with acetylcholinesterase (AChE) inhibition and brain-derived neurotrophic factor (BDNF) activation activity, by linking tacrine and a fragment of huperzine A. However, it was largely unknown whether A10E could act on other AD targets and produce cognitive-enhancing ability in AD animal models. In this study, A10E could prevent cognitive impairments in APP/PS1 transgenic mice and beta-amyloid (Abeta) oligomers-treated mice, with higher potency than tacrine and huperzine A. Moreover, A10E could effectively inhibit Abeta production and deposition, alleviate neuroinflammation, enhance BDNF expression, and elevate cholinergic neurotransmission in vivo. At nanomolar concentrations, A10E could inhibit Abeta oligomers-induced neurotoxicity via the activation of tyrosine kinase receptor B (TrkB)/Akt pathway in SH-SY5Y cells. Furthermore, Abeta oligomerization and fibrillization could be directly disrupted by A10E. Importantly, A10E at high concentrations did not produce obvious hepatotoxicity. Our results indicated that A10E could produce anti-AD neuroprotective effects via the inhibition of Abeta aggregation, the activation of the BDNF/TrkB pathway, the alleviation of neuroinflammation, and the decrease of AChE activity. As MTDLs could produce additional benefits, such as overcoming the deficits of drug combination and enhancing the compliance of AD patients, our results also suggested that A10E might be developed as a promising MTDL lead for the treatment of AD.
The d-amino acid residues are hallmark building blocks of nonribosomal peptides. Here, we report the bifunctional thioesterase domain (TE domain) Skyxy-TE that catalyzes both epimerization and cyclization in skyllamycin biosynthesis. Skyxy-TE specifically catalyzes the epimerization of the C-terminal l-amino acid residue of the linear substrate, then catalyzes regioselective intramolecular cyclization. The crystal structure of Skyxy-TE was solved at 2.25 and site-directed mutagenesis was performed, revealing key residues involved in the epimerization and cyclization. This study expands the understanding of the versatile TE domains and facilitates chemoenzymatic synthesis or combinatorial biosynthesis in the future.
Alzheimer's disease (AD) is a prevalent neurodegenerative disorder that has multiple causes. Therefore, multiple-target-directed ligands (MTDLs), which act on multiple targets, have been developed as a novel strategy for AD therapy. In this study, novel drug candidates were designed and synthesized by the covalent linkings of tacrine, a previously used anti-AD acetylcholinesterase (AChE) inhibitor, and dipicolylamine, an beta-amyloid (Abeta) aggregation inhibitor. Most tacrine-dipicolylamine dimers potently inhibited AChE and Abeta(1-42) aggregation in vitro, and 13a exhibited nanomolar level inhibition. Molecular docking analysis suggested that 13a could interact with the catalytic active sites and the peripheral anion site of AChE, and bind to Abeta(1-42) pentamers. Moreover, 13a effectively attenuated Abeta(1-42) oligomers-induced cognitive dysfunction in mice by activating the cAMP-response element binding protein/brain-derived neurotrophic factor signaling pathway, decreasing tau phosphorylation, preventing synaptic toxicity, and inhibiting neuroinflammation. The safety profile of 13a in mice was demonstrated by acute toxicity experiments. All these results suggested that novel tacrine-dipicolylamine dimers, especially 13a, have multi-target neuroprotective and cognitive-enhancing potentials, and therefore might be developed as MTDLs to combat AD.
Title: Enantioselective Hydrolysis of Styrene Oxide and Benzyl Glycidyl Ether by a Variant of Epoxide Hydrolase from Agromyces mediolanus Jin H, Li Y, Zhang Q, Lin S, Yang Z, Ding G Ref: Mar Drugs, 17:, 2019 : PubMed
Enantiopure epoxides are versatile synthetic intermediates for producing optically active pharmaceuticals. In an effort to provide more options for the preparation of enantiopure epoxides, a variant of the epoxide hydrolase (vEH-Am) gene from a marine microorganism Agromyces mediolanus was synthesized and expressed in Escherichia coli. Recombiant vEH-Am displayed a molecular weight of 43 kDa and showed high stability with a half-life of 51.1 h at 30 degrees C. The purified vEH-Am exhibited high enantioselectivity towards styrene oxide (SO) and benzyl glycidyl ether (BGE). The vEH-Am preferentially converted (S)-SO, leaving (R)-SO with the enantiomeric excess (ee) >99%. However, (R)-BGE was preferentially hydrolyzed by vEH-Am, resulting in (S)-BGE with >99% ee. To investigate the origin of regioselectivity, the interactions between vEH-Am and enantiomers of SO and BGE were analyzed by molecular docking simulation. In addition, it was observed that the yields of (R)-SO and (S)-BGE decreased with the increase of substrate concentrations. The yield of (R)-SO was significantly increased by adding 2% (v/v) Tween-20 or intermittent supplementation of the substrate. To our knowledge, vEH-Am displayed the highest enantioselectivity for the kinetic resolution of racemic BGE among the known EHs, suggesting promising applications of vEH-Am in the preparation of optically active BGE.
Title: Identification and Analysis of Chemical Constituents and Rat Serum Metabolites in Lycopodium clavatum Using UPLC-Q-TOF/MS Combined with Multiple Data-Processing Approaches Li X, Kang M, Ma N, Pang T, Zhang Y, Jin H, Yang Z, Song L Ref: Evid Based Complement Alternat Med, 2019:5165029, 2019 : PubMed
Lycopodium clavatum is a dry whole grass of Lycopodium japonicum Thunb.; it has been extensively used to anti-inflammatory, antioxidant, and antimicrobial actions and inhibits acetylcholinesterase activity. However, it lacks further compounds research of Lycopodium clavatum in vivo and in vitro. In this work, a rapid method was established using the ultra high performance liquid chromatography with quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF/MS) combined with multiple data-processing approaches for compounds analysis of Lycopodium clavatum in vitro and in vivo. Finally, 30 peaks were characterized in 75% ethanol extract of Lycopodium clavatum and 17 peaks were characterized in rat plasma that including 12 prototype compounds and 5 metabolites. Methylation and demethylation are the main transformation reactions of Lycopodium clavatum in rat serum. This work could be helpful for understanding the complex compounds of Lycopodium clavatum and further analyzing the pharmacological studies of active compounds.
Alzheimer's disease (AD) is characterized by progressive neurodegeneration and impaired cognitive functions. Fascaplysin is a beta-carboline alkaloid isolated from marine sponge Fascaplysinopsis bergquist in 1988. Previous studies have shown that fascaplysin might act on acetylcholinesterase and beta-amyloid (Abeta) to produce anti-AD properties. In this study, a series of fascaplysin derivatives were synthesized. The cholinesterase inhibition activities, the neuronal protective effects, and the toxicities of these compounds were evaluated in vitro. Compounds 2a and 2b, the two most powerful compounds in vitro, were further selected to evaluate their cognitive-enhancing effects in animals. Both 2a and 2b could ameliorate cognitive dysfunction induced by scopolamine or Abeta oligomers without affecting locomotor functions in mice. We also found that 2a and 2b could prevent cholinergic dysfunctions, decrease pro-inflammatory cytokine expression, and inhibit Abeta-induced tau hyperphosphorylation in vivo. Most importantly, pharmacodynamics studies suggested that 2b could penetrate the blood-brain barrier and be retained in the central nervous system. All these results suggested that fascaplysin derivatives are potent multitarget agents against AD and might be clinical useful for AD treatment.
Title: Mori Ramulus (Chin.Ph.)-the Dried Twigs of Morus alba L./Part 1: Discovery of Two Novel Coumarin Glycosides from the Anti-Hyperuricemic Ethanol Extract Yao J, He H, Xue J, Wang J, Jin H, Wu J, Hu J, Wang R, Kuchta K Ref: Molecules, 24:, 2019 : PubMed
In Traditional Chinese Medicine (TCM), Mori ramulus (Chin.Ph.)-the dried twigs of Morus alba L.-is extensively used as an antirheumatic agent and also finds additional use in asthma therapy. As a pathological high xanthine oxidase (XO, EC 1.1.3.22) activity is strongly correlated to hyperuricemy and gout, standard anti-hyperuremic therapy typically involves XO inhibitors like allopurinol, which often cause adverse effects by inhibiting other enzymes involved in purine metabolism. Mori ramulus may therefore be a promissing source for the development of new antirheumatic therapeutics with less side effects. Coumarins, one of the dominant groups of bioactive constituents of M. alba, have been demonstrated to possess anti-inflammatory, antiplatelet aggregation, antitumor, and acetylcholinesterase (AChE) inhibitory activities. The combination of HPLC (DAD) and Q-TOF technique could give excellent separating and good structural characterization abilities which make it suitable to analyze complex multi-herbal extracts in TCM. The aim of this study was to develop a HPLC (DAD)/ESI-Q-TOF-MS/MS method for the identification and profiling of pharmacologically active coumarin glycosides in Mori ramulus refined extracts for used in TCM. This HPLC (DAD)/ESI-Q-TOF-MS/MS method provided a rapid and accurate method for identification of coumarin glycosides-including new natural products described here for the first time-in the crude extract of M. alba L. In the course of this project, two novel natural products moriramulosid A (umbelliferone-6-beta-d-apiofuranosyl-(1-->6)-beta-d-glucopyranoside) and moriramulosid B (6-[[6-O-(6-deoxy-alpha-l-mannopyranosyl)-beta-d-glucopyranosyl]oxy]-2H-1-benzopy ran-1-one) were newly discovered and the known natural product Scopolin was identified in M. alba L. for the first time.
Title: Exploration of the chlorpyrifos escape pathway from acylpeptide hydrolases using steered molecular dynamics simulations Wang D, Jin H, Wang J, Guan S, Zhang Z, Han W Ref: J Biomol Struct Dyn, 34:749, 2016 : PubMed
Acylpeptide hydrolases (APH) catalyze the removal of an N-acylated amino acid from blocked peptides. APH is significantly more sensitive than acetylcholinesterase, a target of Alzheimer's disease, to inhibition by organophosphorus (OP) compounds. Thus, OP compounds can be used as a tool to probe the physiological functions of APH. Here, we report the results of a computational study of molecular dynamics simulations of APH bound to the OP compounds and an exploration of the chlorpyrifos escape pathway using steered molecular dynamics (SMD) simulations. In addition, we apply SMD simulations to identify potential escape routes of chlorpyrifos from hydrolase hydrophobic cavities in the APH-inhibitor complex. Two previously proposed APH pathways were reliably identified by CAVER 3.0, with the estimated relative importance of P1 > P2 for its size. We identify the major pathway, P2, using SMD simulations, and Arg526, Glu88, Gly86, and Asn65 are identified as important residues for the ligand leaving via P2. These results may help in the design of APH-targeting drugs with improved efficacy, as well as in understanding APH selectivity of the inhibitor binding in the prolyl oligopeptidase family.
Title: Molecular dynamics simulations of acylpeptide hydrolase bound to chlorpyrifosmethyl oxon and dichlorvos Jin H, Zhou Z, Wang D, Guan S, Han W Ref: Int J Mol Sci, 16:6217, 2015 : PubMed
Acylpeptide hydrolases (APHs) catalyze the removal of N-acylated amino acids from blocked peptides. Like other prolyloligopeptidase (POP) family members, APHs are believed to be important targets for drug design. To date, the binding pose of organophosphorus (OP) compounds of APH, as well as the different OP compounds binding and inducing conformational changes in two domains, namely, alpha/beta hydrolase and beta-propeller, remain poorly understood. We report a computational study of APH bound to chlorpyrifosmethyl oxon and dichlorvos. In our docking study, Val471 and Gly368 are important residues for chlorpyrifosmethyl oxon and dichlorvos binding. Molecular dynamics simulations were also performed to explore the conformational changes between the chlorpyrifosmethyl oxon and dichlorvos bound to APH, which indicated that the structural feature of chlorpyrifosmethyl oxon binding in APH permitted partial opening of the beta-propeller fold and allowed the chlorpyrifosmethyl oxon to easily enter the catalytic site. These results may facilitate the design of APH-targeting drugs with improved efficacy.
"Drying without dying" is an essential trait in land plant evolution. Unraveling how a unique group of angiosperms, the Resurrection Plants, survive desiccation of their leaves and roots has been hampered by the lack of a foundational genome perspective. Here we report the approximately 1,691-Mb sequenced genome of Boea hygrometrica, an important resurrection plant model. The sequence revealed evidence for two historical genome-wide duplication events, a compliment of 49,374 protein-coding genes, 29.15% of which are unique (orphan) to Boea and 20% of which (9,888) significantly respond to desiccation at the transcript level. Expansion of early light-inducible protein (ELIP) and 5S rRNA genes highlights the importance of the protection of the photosynthetic apparatus during drying and the rapid resumption of protein synthesis in the resurrection capability of Boea. Transcriptome analysis reveals extensive alternative splicing of transcripts and a focus on cellular protection strategies. The lack of desiccation tolerance-specific genome organizational features suggests the resurrection phenotype evolved mainly by an alteration in the control of dehydration response genes.
INTRODUCTION: A significant number of mania patients fail to respond to current pharmacotherapy, thereby there is need for novel augmentation strategies. The results of some early studies showed the effectiveness of cholinomimetics in the treatment of mania. One open case series suggested the efficacy of donepezil in the treatment of bipolar disorder. Our aim was to explore whether an oral cholinesterase inhibitor, donepezil, administered during a 4-week treatment period, would benefit patients with acute mania. METHODS: We conducted a 4-week double-blind, placebo-controlled trial of donepezil as an adjunctive treatment to lithium in patients with acute mania. Eligible subjects were randomly assigned to receive donepezil or placebo in addition to lithium. Donepezil was started at 5 mg/day, and increased to 10 mg/day in the first week. Patients were rated with the Young Mania Rating Scale (YMRS) and Brief Psychiatric Rating Scale (BPRS) at baseline, day 1, week 1, week 2, and week 4. RESULTS: Out of the 30 patients who were enrolled, 15 were on donepezil and 15 were on placebo. All patients completed the 4-week trial. On the first day, there was a difference of 1.97 units on the psychomotor symptoms scale of the YMRS in the donepezil group as compared to the placebo group (t = 2.39, P = 0.02). There was a difference of 0.57 units (t = 2.09, P = 0.04) in the speech item and a difference of 0.29 units in the sexual interest item (t = 2.11, P = 0.04) in the donepezil group as compared to the placebo group. The total YMRS difference on the first day approached the conventional significance level (1.97 units, t = 1.84, P = 0.07). Over the course of 4 weeks, we failed to find that donepezil produced any significant difference in the YMRS (6.71 units difference, t = -1.44, P = 0.16) or the BPRS scale (1.29 units difference, t = -0.33, P = 0.75) as compared to placebo. Ten subjects (66.67%) in both groups met the criteria for clinical response (Fisher's exact P = 1.00). Five subjects (33.33%) in the donepezil group met the criteria for clinical remission while nine subjects (60.00%) in the placebo group met the remission criteria (Fisher's exact P = 0.27). CONCLUSION: Use of the oral anticholinergic donepezil had some benefit in the augmentation of lithium treatment on the first day, but did not provide any significant benefits in the long-term.
Mycoplasma columbinum is a member of nonglycolytic Mycoplasma species which can hydrolyze arginine. Increasingly research has revealed that M. columbinum is associated with respiratory disease of pigeons and that the respiratory disease symptoms could be eliminated via the use of mycoplasma treatment medicine. Here we report the genome sequence of M. columbinum strain SF7, which is the first genome report for M. columbinum.
To identify suitable lipophilic compounds having high potency and selectivity for vesicular acetylcholine transporter (VAChT), a heteroaromatic ring or a phenyl group was introduced into the carbonyl-containing scaffold for VAChT ligands. Twenty new compounds with ALogD values between 0.53 and 3.2 were synthesized, and their in vitro binding affinities were assayed. Six of them (19a, 19e, 19g, 19k, and 24a-b) displayed high affinity for VAChT (Ki = 0.93-18 nM for racemates) and moderate to high selectivity for VAChT over sigma1 and sigma2 receptors (Ki = 44-4400-fold). These compounds have a methyl or a fluoro substitution that provides the position for incorporating PET radioisotopes C-11 or F-18. Compound (-)-[(11)C]24b (Ki = 0.78 nM for VAChT, 1200-fold over sigma receptors) was successfully synthesized and evaluated in vivo in rats and nonhuman primates. The data revealed that (-)-[(11)C]24b has highest binding in striatum and has favorable pharmacokinetics in the brain.
Salmonellosis has been one of the major contributors to the global public health burden. Salmonella enterica serotype Agona has ranked among the top 10 and top 20 most frequent Salmonella serotypes isolated from human sources in China and the United States, respectively. We report draft genomes of three S. Agona strains from China.
Salmonellosis contributes significantly to the public health burden globally. Salmonella enterica serotype Newport is among Salmonella serotypes most associated with food-borne illness in the United States and China. It was thought to be polyphyletic and to contain different lineages. We report draft genomes of four S. Newport strains isolated from humans in China.
Mycoplasma iowae is associated mainly with reduced hatchability in turkeys and is well known for the unusual ability of phenotypic variation in the Mycoplasma surface components as well as a relative resistance to heat, bile salts, and many antimicrobials. A subset of unique genes and a gene cluster responsible for these characteristics could be identified from the genome. Here, we report the first genome sequence of this species.
Collybistin promotes submembrane clustering of gephyrin and is essential for the postsynaptic localization of gephyrin and gamma-aminobutyric acid type A (GABA(A)) receptors at GABAergic synapses in hippocampus and amygdala. Four collybistin isoforms are expressed in brain neurons; CB2 and CB3 differ in the C terminus and occur with and without the Src homology 3 (SH3) domain. We have found that in transfected hippocampal neurons, all collybistin isoforms (CB2(SH3+), CB2(SH3-), CB3(SH3+), and CB3(SH3-)) target to and concentrate at GABAergic postsynapses. Moreover, in non-transfected neurons, collybistin concentrates at GABAergic synapses. Hippocampal neurons co-transfected with CB2(SH3-) and gephyrin developed very large postsynaptic gephyrin and GABA(A) receptor clusters (superclusters). This effect was accompanied by a significant increase in the amplitude of miniature inhibitory postsynaptic currents. Co-transfection with CB2(SH3+) and gephyrin induced the formation of many (supernumerary) non-synaptic clusters. Transfection with gephyrin alone did not affect cluster number or size, but gephyrin potentiated the clustering effect of CB2(SH3-) or CB2(SH3+). Co-transfection with CB2(SH3-) or CB2(SH3+) and gephyrin did not affect the density of presynaptic GABAergic terminals contacting the transfected cells, indicating that collybistin is not synaptogenic. Nevertheless, the synaptic superclusters induced by CB2(SH3-) and gephyrin were accompanied by enlarged presynaptic GABAergic terminals. The enhanced clustering of gephyrin and GABA(A) receptors induced by collybistin isoforms was not accompanied by enhanced clustering of neuroligin 2. Moreover, during the development of GABAergic synapses, the clustering of gephyrin and GABA(A) receptors preceded the clustering of neuroligin 2. We propose a model in which the SH3- isoforms play a major role in the postsynaptic accumulation of GABA(A) receptors and in GABAergic synaptic strength.
Mycoplasma anatis, a member of the class Mollicutes, is the causative agent of a contagious infectious disease of domestic ducklings, wild birds, and eggs. Increasing reports show that coinfection of M. anatis with Escherichia coli results in substantial economic impacts on the duck farms in China. Here, we announce the first genome sequence of M. anatis.
We report the annotation and analysis of the draft genome sequence of Brassica rapa accession Chiifu-401-42, a Chinese cabbage. We modeled 41,174 protein coding genes in the B. rapa genome, which has undergone genome triplication. We used Arabidopsis thaliana as an outgroup for investigating the consequences of genome triplication, such as structural and functional evolution. The extent of gene loss (fractionation) among triplicated genome segments varies, with one of the three copies consistently retaining a disproportionately large fraction of the genes expected to have been present in its ancestor. Variation in the number of members of gene families present in the genome may contribute to the remarkable morphological plasticity of Brassica species. The B. rapa genome sequence provides an important resource for studying the evolution of polyploid genomes and underpins the genetic improvement of Brassica oil and vegetable crops.
The release of free fatty acids (FFAs) from adipocytes (i.e. lipolysis) is increased in obesity and is a contributory factor to the development of insulin resistance. A recently identified adipokine, apelin, is up-regulated in states of obesity. Although apelin is secreted by adipocytes, its functions in them remain largely unknown. To determine whether apelin affects lipolysis, FFA, glycerol, and leptin levels, as well as abdominal adiposity, were measured at baseline and after reintroduction of exogenous apelin in apelin-null mice. To examine apelin's effects in vitro, isoproterenol-induced FFA/glycerol release, and hormone-sensitive lipase (HSL) and acetyl CoA carboxylase phosphorylation were investigated in 3T3-L1 cells and isolated wild-type adipocytes. Serum FFA, glycerol, and leptin concentrations, as well as abdominal adiposity, were significantly increased in apelin-null vs. wild-type mice; these changes were ameliorated in response to exogenous apelin. Apelin also reduced isoproterenol-induced FFA release in adipocytes isolated from wild-type but not APJ-null mice. In 3T3-L1 cells and isolated adipocytes, apelin attenuated isoproterenol-induced FFA/glycerol release. Apelin's inhibition was reversed by pertussis toxin, the G(q) inhibitor glycoprotein antagonist 2A, and the AMP-activated protein kinase inhibitors compound C and dorsomorphin. Apelin increased HSL phosphorylation at Ser-565 and also abrogated isoproterenol-induced HSL phosphorylation at Ser-563. Notably, apelin increased acetyl CoA carboxylase phosphorylation, suggesting AMPK activation. In conclusion, apelin negatively regulates lipolysis. Its actions may be mediated by pathways involving G(q), G(i), and AMP-activated protein kinase.
Title: Design, synthesis, and bioactivities screening of a diaryl ketone-inspired pesticide molecular library as derived from natural products Zhang H, Jin H, Ji LZ, Tao K, Liu W, Zhao HY, Hou TP Ref: Chemical Biology Drug Des, 78:94, 2011 : PubMed
Three natural products, 1,5-diphenylpentan-1-one, 1,5-diphenylpent-2-en-1-one, and 3-hydroxy-1,5-diphenylpentan-1-one, with good insecticidal activities were extracted from Stellera chamaejasme L. Based on their shared diaryl ketone moiety as 'pharmacophores', a series of diaryl ketones were synthesized and tested for insecticidal activity, acetylcholinesterase inhibitory activity, and antifungal activity. All synthesized compounds showed poor insecticidal and acetylcholinesterase inhibitory activities. Compound III with a furyl ring showed strong activities against plant pathogenic fungi. The IC(50) of compound (E)-1-(2,4-dichlorophenyl)-3-(furan-2-yl)- -prop-2-en-1-one (III(2) ) was 1.20 mg/L against Rhizoctonia solani, suggesting its strong potential as a novel antifungal drug.
Riemerella anatipestifer is a Gram-negative, rod-shaped bacterium associated with epizootic infections in poultry. R. anatipestifer strain RA-YM, belonging to the serotype 1 prevalent in China, is a clinically isolated strain with high-level virulence. Here, we report the first genome sequence of this species.
Title: Suppression of N-myc downstream-regulated gene 2 is associated with induction of Myc in colorectal cancer and correlates closely with differentiation Shi H, Jin H, Chu D, Wang W, Zhang J, Chen C, Xu C, Fan D, Yao L Ref: Biol Pharm Bull, 32:968, 2009 : PubMed
NDRG2, a new member of the N-Myc downstream-regulated gene (NDRG) family, is a focus for study at present. Up to now, its expression and function in carcinoma remain to be elucidated. In this study, using a colorectal cancer tissue array and a series of 213 colorectal cancer samples, the relationship between Ndrg2 and c-MYC expression and tumor differentiation level was investigated. Immunohistochemistry showed that Ndrg2 expression was reduced and that c-Myc was increased in colorectal carcinomas. In addition, Ndrg2 protein levels increased from poorly differentiated to well-differentiated carcinomas (p=0.005). Real-time polymerase chain reaction and Western blots demonstrated quantitatively that NDRG2 mRNA and protein levels were lower in colorectal carcinomas compared to the adjacent tissue and normal tissue from the same individual (p=3x10(-8)). Also, the NDRG2 expression level in adjacent carcinoma tissue was lower than that of normal tissue. However, the expression pattern of c-MYC was the inverse (p=5x10(-8)). Finally, we induced the differentiation of the colorectal carcinoma cell lines HT29, SW480 and SW620 and found that NDRG2 expression increased and that c-MYC expression declined with increasing differentiation. These novel data show a disparity in both the mRNA and protein expression levels of Ndrg2 and c-Myc between colorectal cancers and normal tissues. Taken together, NDRG2 may play a role during the differentiation of colorectal cancer cells, and the function of NDRG2 in the development of colorectal cancer should be further investigated.
Clear cell renal cell carcinoma (CCRCC) is the most common pathological type of renal cell carcinoma and the main cause of renal carcinoma mortality. NDRG2, a new member of the N-Myc downstream-regulated gene (NDRG) family, is a focus for study at present. Up to now, its expression and function in carcinoma remain unclear. The aim of this study was to investigate its expression in CCRCC tissues and several renal carcinoma cell lines. The expression of NDRG2 was evaluated in renal cell carcinoma cell lines, tumor and adjacent non-tumor tissues from same clear cell renal cell carcinoma patients, by using immunohistochemistry, immunofluorescence, RT-PCR and Western blot. By immunohistochemistry and immunofluorescence we found that NDRG2 was predominantly located in the cytoplasm and membrane of renal carcinoma cancer cells, and the positive rate of NDRG2 in renal carcinoma specimens was 30.3% (40/132), which is significantly lower than 91.67% (121/132) in normal renal tissues (p<0.01). The average staining score in normal renal tissues was significantly higher than renal carcinoma (6.12+/-1.84 versus 2.65+/-1.23, p<0.01). Moreover, NDRG2 mRNA and protein were down-regulated in 6 fresh CCRCC tissues compared with their adjacent noncancerous tissues and normal tissues. Its expression was also lower in the human CCRCC-derived cell lines A-498 and 786-O than in the human proximal tubular cell lines HK-2 and HKC. These results indicated that NDRG2 might play an important role in the carcinogenesis and development of CCRCC and may function as a tumor suppressor in CCRCC.
Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, a cause of considerable world wide economic losses in the swine industry. We sequenced the complete genome of A. pleuropneumoniae, JL03, an isolate of serotype 3 prevalent in China. Its genome is a single chromosome of 2,242,062 base pairs containing 2,097 predicted protein-coding sequences, six ribosomal rRNA operons, and 63 tRNA genes. Preliminary analysis of the genomic sequence and the functions of the encoded proteins not only confirmed the present physiological and pathological knowledge but also offered new insights into the metabolic and virulence characteristics of this important pathogen. We identified a full spectrum of genes related to its characteristic chemoheterotrophic catabolism of fermentation and respiration with an incomplete TCA system for anabolism. In addition to confirming the lack of ApxI toxin, identification of a nonsense mutation in apxIVA and a 5'-proximal truncation of the flp operon deleting both its promoter and the flp1flp2tadV genes have provided convincing scenarios for the low virulence property of JL03. Comparative genomic analysis using the available sequences of other serotypes, probable strain (serotype)-specific genomic islands related to capsular polysaccharides and lipopolysaccharide O-antigen biosyntheses were identified in JL03, which provides a foundation for future research into the mechanisms of serotypic diversity of A. pleuropneumoniae.
Title: A fragmented aflatoxin-like gene cluster in the forest pathogen Dothistroma septosporum Zhang S, Schwelm A, Jin H, Collins LJ, Bradshaw RE Ref: Fungal Genet Biol, 44:1342, 2007 : PubMed
The polyketide toxin dothistromin is very similar in structure to the aflatoxin precursor, versicolorin B. Dothistromin is made by a pine needle pathogen, Dothistroma septosporum, both in culture and in planta. Orthologs of aflatoxin biosynthetic genes have been identified that are required for dothistromin biosynthesis in D. septosporum. In contrast to the situation in aflatoxin-producing fungi where 25 aflatoxin biosynthetic and regulatory genes are tightly clustered in one region of the genome, the dothistromin gene cluster is fragmented. Three mini-clusters of dothistromin genes have been identified, each located on a 1.3-Mb chromosome and each grouped with non-dothistromin genes. There are no obvious patterns of repeated sequences or transposon relics to suggest recent recombination events. Most dothistromin genes within the mini-clusters are co-regulated, suggesting that coordinate control of gene expression is achieved despite this unusual arrangement of secondary metabolite biosynthetic genes.
Dothistromin is a polyketide toxin, produced by a fungal forest pathogen, with structural similarity to the aflatoxin precursor versicolorin B. Biochemical and genetic studies suggested that there are common steps in the biosynthetic pathways for these metabolites and showed similarities between some of the genes. A polyketide synthase gene (pksA) was isolated from dothistromin-producing Dothistroma septosporum by hybridization with an aflatoxin ortholog from Aspergillus parasiticus. Inactivation of this gene in D. septosporum resulted in mutants that could not produce dothistromin but that could convert exogenous aflatoxin precursors, including norsolorinic acid, into dothistromin. The mutants also had reduced asexual sporulation compared to the wild type. So far four other genes are known to be clustered immediately alongside pksA. Three of these (cypA, moxA, avfA) are predicted to be orthologs of aflatoxin biosynthetic genes. The other gene (epoA), located between avfA and moxA, is predicted to encode an epoxide hydrolase, for which there is no homolog in either the aflatoxin or sterigmatocystin gene clusters. The pksA gene is located on a small chromosome of approximately 1.3 Mb in size, along with the dothistromin ketoreductase (dotA) gene.
Modification of fumagillin was conducted to develop MetAP-2 inhibitors with desirable pharmacological properties. Replacement of the C4 side chain by benzyloxime preserves the inhibitory activity against MetAP-2 enzyme. Fumagillin analogues containing the C4 benzyloxime moiety were found to be very sensitive to the nature of the C6 substituent on the inhibition activity of HUVEC proliferation. This lack of correlation between MetAP-2 and HUVEC activities might be due to the cellular metabolism of the compounds by epoxide hydrolase, which is present in the cell. Compound (E)-3d, containing ethylpiperazinyl carbamate at C6 position, exhibited antiangiogenic effects similar to TNP-470 on matrigel plug assay and rat corneal micropocket assay.
Title: [A comparative study on the sensitivity and specificity of cholinesterase and glutathione s-transferase in Gammarus pulex L.] Yin D, Jin H, Yu H, Chen L Ref: Ying Yong Sheng Tai Xue Bao, 12:615, 2001 : PubMed
Studies on the influences of lindane, pirimiphos, methyl, permethrin, zinc and dodecyl linear alkybenzene sulfonate LAS, on the activity and toxicity of cholinesterase ChE and glutathione s-transferase GST in Gammarus pulex L showed that only pirimiphos methyl caused a change in ChE activity in Gammarus with a significant reduction in enzyme activity after 24 h and 48 h exposure. Both lindane and permethrin caused a change in GST activity in Gammarus with a significant increase in enzyme activity after 48 h exposure. Lindane alos caused a significant increase in GST activity after 24 h exposure. Biomarkers ChE and GST were demonstrated a high degree of specificity and sensitivity in comparison to the lethality assay but GST activity was less specific than ChE activity.
