Multiple Phenotypes in Adult Mice following Inactivation of the Coxsackievirus and Adenovirus Receptor (Car) Gene

To determine the normal function of the Coxsackievirus and Adenovirus Receptor (CAR), a protein found in tight junctions and other intercellular complexes, we constructed a mouse line in which the CAR gene could be disrupted at any chosen time point in a broad spectrum of cell types and tissues. All knockouts examined displayed a dilated intestinal tract and atrophy of the exocrine pancreas with appearance of tubular complexes characteristic of acinar-to-ductal metaplasia. The mice also exhibited a complete atrio-ventricular block and abnormal thymopoiesis. These results demonstrate that CAR exerts important functions in the physiology of several organs in vivo

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Molecular and functional studies of interleukin-1a in the rat testis

The aim of the present study was to gain a better insight into the role of interleukin-1 alpha (IL-1 alpha) in testicular physiology. In testis, IL-1alpha acts as a paracrine mediator involved in the regulation of testicular functions. Bioactive IL-1 alpha isolated and characterized from adult rat testis, showed the presence of several distinct protein species, with a size range of 17-40 kDa and charge heterogeneity. The present study was undertaken to clarify the molecular heterogeneity and to characterize different isoforms of IL-1alpha in rat testis and to study the processing, secretion, regulation and function of these isoforms. The physicochemical characterization revealed that testicular IL-1 alpha is similar to IL-1 alpha from activated macrophages. IL-1 bioactivity of crude testis protein was completely neutralized by IL-1 alpha antiserum, IL-1 receptor antagonist and soluble type 1 IL-1 receptor. Three isoforms of IL-1 alpha proteins with molecular sizes of 45, 31 and 17 kDa and at charges of pH 5.7 and 6.0 are found in the testis. All three forms are secreted into the interstitial compartment and tubular lumen. Molecular characterization revealed that heterogeneity also existed at the transcriptional level and a novel splice variant was found and named as 24proIL-1 alpha. It lacked exon 5, which harbors the cleavage site of the processing enzyme calpain. Expression of these isoforms in COS. cells and in vitro calpain cleavage assay of recombinant protein expressed in E. coli confirmed that 32proI1l-1 alpha was processed to produce 17 kDa whereas 24proIL- 1 alpha was resistant to cleavage. Both forms were bioactive in thymocyte proliferation IL-1 bioassay. However, these isoforms showed differential activity on human chorionic gonadotropin (hCG)-induced Leydig cell steroidogenesis. 32proIL-1 alpha was inhibitory and 24proIL-1 alpha showed no effect. On analysis of mechanism of action, 24proIL- 1alpha showed weak but significant stimulation of hCG-induced steroidogenesis in Leydig cells from 40- day-old rats, while 32proIL-1 alpha was inhibitory. All IL-1 isoforms showed stimulation of basal testosterone production in Leydig cell from 40-day-old rats but not 80-dayold rats. These effects were receptor-mediated, and protein kinase A and Ca 2+ seemed to be involved as major components of the IL- 1 alpha signaling cascade. IL-1 alpha isoforms stimulated proliferation of T lymphocytes and growth of immature Sertoli cells. All isoforms were active in both growth assays and showed differential biopotencies in the following order: 17 kDa IL-1 alpha > 32proIL-1 alpha > 24proIL-1 alpha. On analysis of the subcellular localization of IL-1 alpha isoforms, COS-1 and CHO showed differential subcellular localization of these isoforms, where 24proIL-1 alpha in CHO cells showed granular appearance. The MSC-1 Sertoli cell line expressed IL- 1 alpha constitutively. The regulation of IL-1 alpha was studied at the level of the enzyme calpain, the key regulator of production of the mature 17 kDa form of IL-1 alpha from 32proIL-1alpha. Both calpains (1 and 11) cleaved recombinant 32proIL-1alpha in vitro. In response to LPS, calpain I protein levels were downregulated in seminiferous tubules whereas calpain II was less affected. By contrast, liver after LPS treatment showed up-regulated expression of calpain I and II. In summary, the study showed that testicular IL-1 alpha exists in three isoforms that are secreted into the tubular lumen and interstitial space. These isoforms showed bioactivity with differential biopotencies. Thus IL-1 alpha acts as a paracrine factor in adult rat testis

Role of testicular interleukin-1alpha tIL-1alpha in testicular physiology and disease

This review focuses on the role of the cytokine interleukin-1alpha (IL-1alpha) in the testis; elaborating upon its importance during the complex process of spermatogenesis while relating this cytokine to some of the pathophysiological states affecting the testis. IL-1alpha, a proinflammatory cytokine, is expressed constitutively by the intact adult rat testis where it acts on germ, Sertoli and Leydig cells to regulate germ cell proliferation and steroidogenesis. The sequence identity of testicular IL-1alpha matches with the one secreted by activated macrophages in systemic immunity. The classical macrophage IL-1alpha is produced as 32 kDa precursor protein which is processed to mature 17 kDa IL-1alpha and a 16 kDa propiece. The rat testicular IL-1alpha, mainly secreted by Sertoli cells, was found to have molecular heterogeneity that can be observed both at the transcriptional and the translational levels. In the rat testis, two transcripts were found to be expressed with 941 bp and 767 bp (that lacks 174 bp) which were translated into 32 kDa and 24 kDa precursor proteins, respectively. The 32 kDa precursor protein is processed to the 17 kDa mature IL-1alpha. Identical transcripts are also shown to be present in cat, dog and pig. Most of the functional role is assigned to the mature 17 kDa IL-1alpha isoform. However, functional analysis of recombinant rat IL-1alpha isoforms showed that there was a clear biopotency difference between these forms in order of 17 kDa IL-1alpha\u3e32proIL-1alpha\u3e24proIL-1alpha. Furthermore, the mature 17 kDa tIL-1alpha has also been implicated in pathologies such as orchitis, relapse of acute lymphoblastic leukemia (ALL) in the testis and infertility disorders in men. Thus, tIL-1alpha may play an important functional role both in coordination of normal testicular physiology as well as in contributing to the disease states in the testis

CcpN: a moonlighting protein regulating catabolite repression of gluconeogenic genes in Bacillus subtilis also affects cell length and interacts with DivIVA

CcpN is a transcriptional repressor in Bacillus subtilis that binds to the promoter region of gapB and pckA, downregulating their expression in the presence of glucose. CcpN also represses sr1, which encodes a small non-coding regulatory RNA that suppresses the arginine biosynthesis gene cluster. CcpN has homologues in other Gram-positive bacteria including Enterococcus faecalis. We report the interaction of CcpN with DivIVA of B. subtilis as determined using Bacterial two-hybrid and GST pull-down assays. Insertional inactivation of CcpN leads to cell elongation and formation of straight chains of cells. These findings suggest that CcpN is a moonlighting protein involved in both gluconeogenesis and cell elongation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Cinnamon Leaf and Clove Essential Oils Are Potent Inhibitors of Candida albicans Virulence Traits

Plant-based essential oils are promising anti-virulence agents against the multidrug-resistant opportunistic pathogen Candida albicans. Gas chromatography–mass spectrometry of Cinnamomum zeylanicum (cinnamon) leaf and Eugenia caryophyllus (clove) flower bud essential oils revealed eugenol (73 and 75%, respectively) as their major component, with β-caryophyllene, eugenyl acetate, and α-humulene as common minor components. Cinnamon leaf and clove essential oils had minimum inhibitory concentrations of 600 and 500 µg/mL, respectively against the C. albicans RSY150 reference strain and 1000 and 750 µg/mL, respectively for the clinical reference strain ATCC 10231. The combined oils are additive (FICI = 0.72 ± 0.16) and synergistic (0.5 ± 0.0) against RSY150 and the clinical reference strain, respectively. Mycelial growth was inhibited by sublethal concentrations of either essential oil, which abolished colony growth. At half of the lowest combined lethal concentration for the two oils, the yeast-to-hyphal transition and mycelial growth was potently inhibited. Mutant strains als1Δ/Δ, als3Δ/Δ, hwp1Δ/HWP1+, and efg1Δ/Δ were sensitive to either or both oils, especially efg1Δ/Δ. In conclusion, oils of cinnamon leaf and clove and their combination significantly impact C. albicans virulence by inhibiting hyphal and mycelial growth

Host Cell Geometry and Cytoskeletal Organization Governs Candida-Host Cell Interactions at the Nanoscale

Candida is one of the most common opportunistic fungal pathogens in humans. Its adhesion to the host cell is required in parasitic states, and is important for pathogenesis. Many studies have shown that there is an increased risk of developing candidiasis when normal tissue barriers are weakened or when immune defences are compromised for example during cancer treatment that induces immunosuppression. The mechanical properties of malignant cells, such as adhesiveness and viscoelasticity, which contribute to cellular invasion and migration are different from those of non-cancerous cells. To understand host invasion and its relationship with host cell health, we probed the interaction of Candida spp. with cancerous and non-cancerous human cell lines using atomic force microscopy in single cell force spectroscopy mode. There was significant adhesion between Candida and human cells, with more adhesion to cancerous versus non-cancerous cell lines. This increase in adhesion is related to the mechanobiological properties of cancer cells which have a disorganized cytoskeleton and lower rigidity. Altered geometry and cytoskeletal disruption of the human cells impacted adhesion parameters, underscoring the role of cytoskeletal organisation in Candida-human cel