Effect of drought on phytyl wax esters in Phaseolus leaves

The small amount of phytol which is bound as wax ester in mature bean leaves is increased 10–20 fold by drought. Watering the plants before permanent wilt reverses this trend. Maximum amounts of phytyl wax esters in plants still viable are higher in the drought resistant tepary bean (Phaseolus acutifolius) than in the less resistant garden bean (P. vulgaris).     

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.     

Tetracycline Residues and Tetracycline Resistance Genes in Groundwater Impacted by Swine Production Facilities

Antibiotics are used at therapeutic levels to treat disease; at slightly lower levels as prophylactics; and at low, subtherapeutic levels for growth promotion and improvement of feed efficiency. Over 88% of swine producers in the United States gave antimicrobials to grower/finisher pigs in feed as a growth promoter in 2000. It is estimated that ca. 75% of antibiotics are not absorbed by animals and are excreted in urine and feces. The extensive use of antibiotics in swine production has resulted in antibiotic resistance in many intestinal bacteria, which are also excreted in swine feces, resulting in dissemination of resistance genes into the environment.

To assess the impact of manure management on groundwater quality, groundwater samples have been collected near two swine confinement facilities that use lagoons for manure storage and treatment. Several key contaminant indicators—including inorganic ions, antibiotics, and antibiotic resistance genes—were analyzed in groundwater collected from the monitoring wells. Chloride, ammonium, potassium, and sodium were predominant inorganic constituents in the manure samples and served as indicators of groundwater contamination. Based on these analyses, shallow groundwater has been impacted by lagoon seepage at both sites. Liquid chromatography-mass spectroscopy (LC-MS) was used to measure the dissolved concentrations of tetracycline, chlortetracycline, and oxytetracycline in groundwater and manure. Although tetracyclines were regularly used at both facilities, they were infrequently detected in manure samples and then at relatively trace concentrations. Concentrations of all tetracyclines and their breakdown products in the groundwater sampled were generally less than 0.5 μg/L.

Bacterial tetracycline resistance genes served as distinct genotypic markers to indicate the dissemination and mobility of antibiotic resistance genes that originated from the lagoons. Applying PCR to genomic DNA extracted from the lagoon and groundwater samples, four commonly occurring tetracycline (tet) resistance genes—tet(M), tet(O), tet(Q), and tet(W)—were detected. The detection frequency of tet genes was much higher in wells located closer to and down-gradient from the lagoons than in wells more distant from the lagoons. These results suggested that in the groundwater underlying both facilities tetracycline resistance genes exist and are somewhat persistent, but that the distribution and potentially the flux for each tet gene varied throughout the study period.     

M phase phosphoprotein 1 is a human plus-end-directed kinesin-related protein required for cytokinesis

The human M phase phosphoprotein 1 (MPP1), previously identified through a screening of a subset of proteins specifically phosphorylated at the G2/M transition (Matsumoto-Taniura, N., Pirollet, F., Monroe, R., Gerace, L., and Westendorf, J. M. (1996) Mol. Biol. Cell 7, 1455-1469), is characterized as a plus-end-directed kinesin-related protein. Recombinant MPP1 exhibits in vitro microtubule-binding and microtubule-bundling properties as well as microtubule-stimulated ATPase activity. In gliding experiments using polarity-marked microtubules, MPP1 is a slow molecular motor that moves toward the microtubule plus-end at a 0.07 microm/s speed. In cycling cells, MPP1 localizes mainly to the nuclei in interphase. During mitosis, MPP1 is diffuse throughout the cytoplasm in metaphase and subsequently localizes to the midzone to further concentrate on the midbody. MPP1 suppression by RNA interference induces failure of cell division late in cytokinesis. We conclude that MPP1 is a new mitotic molecular motor required for completion of cytokinesis.     

Apolipoprotein A-V association with intracellular lipid droplets

Apolipoprotein A-V (apoA-V) plays a key role in the regulation of triglyceride (TG) metabolism. Given the very low concentration of apoA-V in plasma, we hypothesized that apoA-V may influence plasma TG levels by affecting the assembly and/or secretion of apoB-containing lipoproteins. When apoA-V was overexpressed in cultured Hep3B cells, neither the amount of apoB secreted nor the density distribution of apoB-containing lipoproteins was affected. Fluorescence microscopy and cell lysate immunoprecipitation studies revealed that apoA-V is not associated with apoB intracellularly, yet immunoprecipitation of apoA-V from the cell culture medium resulted in coprecipitation of apoB. These data suggest that the apoA-V association with apoB-containing lipoproteins is a postsecretory event. Confocal fluorescence microscopy revealed the presence of apoA-V in distinct cellular structures. Based on Nile Red staining, we identified these structures to be intracellular lipid droplets. These data suggest that apoA-V has a unique association with cellular lipids and, therefore, may be involved in the storage or mobilization of intracellular lipids.     

Arginine Vasotocin Injection Increases Probability of Calling in Cricket Frogs, but Causes Call Changes Characteristic of Less Aggressive Males

Male cricket frogs,Acris crepitanscommunicate to males and females using advertisement calls, which are arranged into call groups. Calls at the middle and end, but not beginning of the call group, are modified in response to male–male aggressive interactions. We found in this field study of male cricket frogs in natural breeding choruses that the peptide hormone arginine vasotocin (AVT) not only increased the probability that males called after injections, but also caused modifications in middle and end calls to produce calls characteristic of less aggressive males. Moreover, AVT-injected males showed significantly greater increases in call dominant frequency than saline-injected males, again, a characteristic of less aggressive males. Cricket frog calls are used to both repel males and attract females, thus call changes may relate to male–male and/or male–female interactions. Saline-injected males also demonstrated significant changes in several call traits, including changes that occurred in the beginning and middle calls of the call groups, but not the end calls. AVT appeared to block some call changes produced through handling. These data suggest that AVT can influence acoustic communication in frogs in several ways, including effects on call characteristics and dominant frequency, as well as potentially blocking some handling effects.     

Membrane-type MMPs enable extracellular matrix permissiveness and mesenchymal cell proliferation during embryogenesis

Peri-cellular remodeling of mesenchymal extracellular matrices is considered a prerequisite for cell proliferation, motility and development. Here we demonstrate that membrane-type 3 MMP, MT3-MMP, is expressed in mesenchymal tissues of the skeleton and in peri-skeletal soft connective tissue. Consistent with this localization, MT3-MMP-deficient mice display growth inhibition tied to a decreased viability of mesenchymal cells in skeletal tissues. We document that MT3-MMP works as a major collagenolytic enzyme, enabling cartilage and bone cells to cleave high-density fibrillar collagen and modulate their resident matrix to make it permissive for proliferation and migration. Collectively, these data uncover a novel extracellular matrix remodeling mechanism required for proper function of mesenchymal cells. The physiological significance of MT3-MMP is highlighted in mice double deficient for MT1-MMP and MT3-MMP. Double deficiency transcends the combined effects of the individual single deficiencies and leads to severe embryonic defects in palatogenesis and bone formation incompatible with life. These defects are directly tied to loss of indispensable collagenolytic activities required in collagen-rich mesenchymal tissues for extracellular matrix remodeling and cell proliferation during embryogenesis.     

Site‐specific contribution of Toll‐like receptor 4 to intestinal homeostasis and inflammatory disease

Toll‐like receptor 4 (TLR4) is a highly conserved protein of innate immunity, responsible for the regulation and maintenance of homeostasis, as well as immune recognition of external and internal ligands. TLR4 is expressed on a variety of cell types throughout the gastrointestinal tract, including on epithelial and immune cell populations. In a healthy state, epithelial cell expression of TLR4 greatly assists in homeostasis by shaping the host microbiome, promoting immunoglobulin A production, and regulating follicle‐associated epithelium permeability. In contrast, immune cell expression of TLR4 in healthy states is primarily centred on the maturation of dendritic cells in response to stimuli, as well as adequately priming the adaptive immune system to fight infection and promote immune memory. Hence, in a healthy state, there is a clear distinction in the site‐specific roles of TLR4 expression. Similarly, recent research has indicated the importance of site‐specific TLR4 expression in inflammation and disease, particularly the impact of epithelial‐specific TLR4 on disease progression. However, the majority of evidence still remains ambiguous for cell‐specific observations, with many studies failing to provide the distinction of epithelial versus immune cell expression of TLR4, preventing specific mechanistic insight and greatly impacting the translation of results. The following review provides a critical overview of the current understanding of site‐specific TLR4 activity and its contribution to intestinal/immune homeostasis and inflammatory diseases.     

An Immunochip-based interrogation of scleroderma susceptibility variants identifies a novel association at DNASE1L3

Introduction

The aim of the study was to interrogate the genetic architecture and autoimmune pleiotropy of scleroderma susceptibility in the Australian population.

Methods

We genotyped individuals from a well-characterized cohort of Australian scleroderma patients with the Immunochip, a custom array enriched for single nucleotide polymorphisms (SNPs) at immune loci. Controls were taken from the 1958 British Birth Cohort. After data cleaning and adjusting for population stratification the final dataset consisted of 486 cases, 4,458 controls and 146,525 SNPs. Association analyses were conducted using logistic regression in PLINK. A replication study was performed using 833 cases and 1,938 controls.

Results

A total of eight loci with suggestive association (P <10^-4.5) were identified, of which five showed significant association in the replication cohort (HLA-DRB1, DNASE1L3, STAT4, TNP03-IRF5 and VCAM1). The most notable findings were at the DNASE1L3 locus, previously associated with systemic lupus erythematosus, and VCAM1, a locus not previously associated with human disease. This study identified a likely functional variant influencing scleroderma susceptibility at the DNASE1L3 locus; a missense polymorphism rs35677470 in DNASE1L3, with an odds ratio of 2.35 (P = 2.3 × 10⁻¹⁰) in anti-centromere antibody (ACA) positive cases.

Conclusions

This pilot study has confirmed previously reported scleroderma associations, revealed further genetic overlap between scleroderma and systemic lupus erythematosus, and identified a putative novel scleroderma susceptibility locus.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-014-0438-8) contains supplementary material, which is available to authorized users.