LF-15 & T7, synthetic peptides derived from tumstatin, attenuate aspects of airway remodelling in a murine model of chronic OVA-induced allergic airway disease

Background: Tumstatin is a segment of the collagen-IV protein that is markedly reduced in the airways of asthmatics. Tumstatin can play an important role in the development of airway remodelling associated with asthma due to its antiangiogenic properties. This study assessed the anti-angiogenic properties of smaller peptides derived from tumstatin, which contain the interface tumstatin uses to interact with the aVb3 integrin. Methods: Primary human lung endothelial cells were exposed to the LF-15, T3 and T7 tumstatin-derived peptides and assessed for cell viability and tube formation in vitro. The impact of the anti-angiogenic properties on airways hyperresponsiveness (AHR) was then examined using a murine model of chronic OVA-induced allergic airways disease. Results: The LF-15 and T7 peptides significantly reduced endothelial cell viability and attenuated tube formation in vitro. Mice exposed to OVA+ LF-15 or OVA+T7 also had reduced total lung vascularity and AHR was attenuated compared to mice exposed to OVA alone. T3 peptides reduced cell viability but had no effect on any other parameters. Conclusion: The LF-15 and T7 peptides may be appropriate candidates for use as novel pharmacotherapies due to their small size and anti-angiogenic properties observed in vitro and in vivo. © 2014 Grafton et al

Structural Alterations in a Component of Cytochrome c Oxidase and Molecular Evolution of Pathogenic Neisseria in Humans

Three closely related bacterial species within the genus Neisseria are of importance to human disease and health. Neisseria meningitidis is a major cause of meningitis, while Neisseria gonorrhoeae is the agent of the sexually transmitted disease gonorrhea and Neisseria lactamica is a common, harmless commensal of children. Comparative genomics have yet to yield clear insights into which factors dictate the unique host-parasite relationships exhibited by each since, as a group, they display remarkable conservation at the levels of nucleotide sequence, gene content and synteny. Here, we discovered two rare alterations in the gene encoding the CcoP protein component of cytochrome cbb3 oxidase that are phylogenetically informative. One is a single nucleotide polymorphism resulting in CcoP truncation that acts as a molecular signature for the species N. meningitidis. We go on to show that the ancestral ccoP gene arose by a unique gene duplication and fusion event and is specifically and completely distributed within species of the genus Neisseria. Surprisingly, we found that strains engineered to express either of the two CcoP forms conditionally differed in their capacity to support nitrite-dependent, microaerobic growth mediated by NirK, a nitrite reductase. Thus, we propose that changes in CcoP domain architecture and ensuing alterations in function are key traits in successive, adaptive radiations within these metapopulations. These findings provide a dramatic example of how rare changes in core metabolic proteins can be connected to significant macroevolutionary shifts. They also show how evolutionary change at the molecular level can be linked to metabolic innovation and its reversal as well as demonstrating how genotype can be used to infer alterations of the fitness landscape within a single host

Diverse Roles and Interactions of the SWI/SNF Chromatin Remodeling Complex Revealed Using Global Approaches

A systems understanding of nuclear organization and events is critical for determining how cells divide, differentiate, and respond to stimuli and for identifying the causes of diseases. Chromatin remodeling complexes such as SWI/SNF have been implicated in a wide variety of cellular processes including gene expression, nuclear organization, centromere function, and chromosomal stability, and mutations in SWI/SNF components have been linked to several types of cancer. To better understand the biological processes in which chromatin remodeling proteins participate, we globally mapped binding regions for several components of the SWI/SNF complex throughout the human genome using ChIP-Seq. SWI/SNF components were found to lie near regulatory elements integral to transcription (e.g. 5′ ends, RNA Polymerases II and III, and enhancers) as well as regions critical for chromosome organization (e.g. CTCF, lamins, and DNA replication origins). Interestingly we also find that certain configurations of SWI/SNF subunits are associated with transcripts that have higher levels of expression, whereas other configurations of SWI/SNF factors are associated with transcripts that have lower levels of expression. To further elucidate the association of SWI/SNF subunits with each other as well as with other nuclear proteins, we also analyzed SWI/SNF immunoprecipitated complexes by mass spectrometry. Individual SWI/SNF factors are associated with their own family members, as well as with cellular constituents such as nuclear matrix proteins, key transcription factors, and centromere components, implying a ubiquitous role in gene regulation and nuclear function. We find an overrepresentation of both SWI/SNF-associated regions and proteins in cell cycle and chromosome organization. Taken together the results from our ChIP and immunoprecipitation experiments suggest that SWI/SNF facilitates gene regulation and genome function more broadly and through a greater diversity of interactions than previously appreciated

Lamstatin - a novel inhibitor of lymphangiogenesis derived from collagen IV

The lymphatic system is essential for the maintenance of tissue homeostasis and immunity. Its dysfunction in disease (such as lymphangioleiomyomatosis) can lead to chylous effusions, oedema or dissemination of malignant cells. Collagen IV has six α chains, of which some of the non-collagenous-1 domains have endogenous anti-angiogenic properties, however, little is known about specific endogenous anti-lymphangiogenic characteristics. In this study we sought to investigate the expression levels of collagen IV non-collagenous-1 domains in lung tissue of patients with and without lymphangioleiomyomatosis to explore the hypothesis that a member of the collagen IV family, specifically the non-collagenous domain-1 of α5, which we named lamstatin, has anti-lymphangiogenic properties. Levels of lamstatin detected by immunohistochemistry were decreased in lungs of lymphangioleiomyomatosis patients. We produced recombinant lamstatin in an E.coli expression system and synthesized a 17-amino acid peptide from a theoretically identified, active region (CP17) and tested their effects in vitro and in vivo. Recombinant lamstatin and CP17 inhibited proliferation, migration and cord formation of human microvascular lung lymphatic endothelial cells, in vitro. Furthermore, lamstatin and CP17 decreased complexity and dysplasia of the tumour-associated lymphatic network in a lung adenocarcinoma xenograft mouse model. In this study we identified a novel, direct inhibitor of lymphangiogenesis, derived from collagen IV. This may prove useful for exploring new avenues of treatment for lymphangioleiomyomatosis and metastasis via the lymphatic system in general. © 2012 The Authors Journal of Cellular and Molecular Medicine © 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd

The phosphoinositide 3 '-kinase p110 delta modulates contractile protein production and IL-6 release in human airway smooth muscle

Transforming growth factor (TGF) beta 1 increases pro-inflammatory cytokines and contractile protein expression by human airway smooth muscle (ASM) cells, which could augment airway inflammation and hyperresponsiveness. Phosphoinositide 3' kinase (PI3K

β<inf>2</inf>-agonist induced cAMP is decreased in asthmatic airway smooth muscle due to increased PDE4D

Background and Objective: Asthma is associated with airway narrowing in response to bronchoconstricting stimuli and increased airway smooth muscle (ASM) mass. In addition, some studies have suggested impaired β-agonist induced ASM relaxation in asthmatics, but the mechanism is not known. Objective: To characterize the potential defect in β-agonist induced cAMP in ASM derived from asthmatic in comparison to non-asthmatic subjects and to investigate its mechanism. Methods: We examined β2-adrenergic (β2AR) receptor expression and basal β-agonist and forskolin (direct activator of adenylyl cyclase) stimulated cAMP production in asthmatic cultured ASM (n = 15) and non-asthmatic ASM (n = 22). Based on these results, PDE activity, PDE4D expression and cell proliferation were determined. Results: In the presence of IBMX, a pan PDE inhibitor, asthmatic ASM had ∼50% lower cAMP production in response to isoproterenol, albuterol, formoterol, and forskolin compared to non-asthmatic ASM. However when PDE4 was specifically inhibited, cAMP production by the agonists and forskolin was normalized in asthmatic ASM. We then measured the amount and activity of PDE4, and found ∼2-fold greater expression and activity in asthmatic ASM compared to non-asthmatic ASM. Furthermore, inhibition of PDE4 reduced asthmatic ASM proliferation but not that of non-asthmatic ASM. Conclusion: Decreased β-agonist induced cAMP in ASM from asthmatics results from enhanced degradation due to increased PDE4D expression. Clinical manifestations of this dysregulation would be suboptimal β-agonist-mediated bronchodilation and possibly reduced control over increasing ASM mass. These phenotypes appear to be "hard-wired" into ASM from asthmatics, as they do not require an inflammatory environment in culture to be observed. © 2011 Trian et al

Rhinovirus-induced exacerbations of asthma: How is the β<inf>2</inf>- adrenoceptor implicated?

Rhinovirus (RV) infections are the major cause of asthma exacerbations in children and adults. Under normal circumstances, asthmatic airway obstruction improves spontaneously or characteristically briskly in response to inhaled β2-adrenergic receptor (β2AR) agonists. During virus-associated exacerbations, an impaired response to β2AR agonists is observed; the reason for this is not known. The objective of this study was to determine the effect of RV infection on airway smooth muscle β2AR function. The human cell line Beas-2B and primary human bronchial epithelial cells (HBECs) were infected with RV (multiplicity of infection = 1). After 1 or 5 days for primary and Beas-2B cells, respectively, cell culture supernatants were harvested, UV-irradiated to inactivate RV, and applied to human airway smooth muscle cells for 3 days to assess modifications of β2AR function. RV conditioned medium from Beas-2B and HBECs decreased β2AR agonist-induced cAMP by 50 and 65%, respectively (n = 5; P < 0.05). When cAMP was induced independently of the β2AR using forskolin, no impairment was found. Using flow cytometry, we demonstrated that this decrease was likely the result of β2AR desensitization because membrane but not total cell receptor β2AR was decreased. Pretreatment of HBECs and Beas-2B cells but not human airway smooth muscle cells with the corticosteroids dexamethasone or fluticasone abolished virus-mediated β2AR loss of function. This study shows that epithelial infection with RV induces a decrease of β2AR function on airway smooth muscle cells, potentially explaining the clinical observation of loss of β2AR agonist function during RV-induced asthma exacerbations

Supernumerary (B) chromosomes in populations of Picea abies (L.) H. Karst. from Western Rhodopes (Bulgaria)

Investigations on B chromosomes found for the first time for Picea abies (L.) H. Karst. have been conducted. Seeds of Picea abies from two populations of Western Rhodopes (Bulgaria) located at the southern border of species range, and protected according to Bern Convention and EC Habitat Directive were collected for this study. Mixoploidy was detected in some germinating seeds of Picea abies. It was found that metaphase cells of germinating seeds contain 0–4 B chromosomes of both metacentric and submetacentric types. The variability of B chromosomes number and their occurrence was observed. Along with B chromosomes, some chromosome aberrations such as fragments and ring chromosomes were revealed in metaphase cells of Picea abies from studied populations. The possible adaptive role of B chromosomes presence for Picea spp. is discussed.Проведено исследование В-хромосом, обнаруженных впервые у вида Picea abies (L.) H. Karst. Для настоящего исследования семена собраны из двух популяций Picea abies в Западных Родопах (Болгария), расположенных на южной границе видового ареала и охраняемых в соответствии с Бернской конвенцией и Директивой ЕС о местообитаниях. В отдельных проростках семян Picea abies найдена миксоплоидия. Обнаружено, что метафазные клетки проростков семян из изученных популяций Picea abies содержат 0–4 В-хромосомы как метацентрического, так и субметацентрического типов. Наблюдается изменчивость числа В-хромосом и их появления. Наряду с В-хромосомами в метафазных клетках Picea abies выявлены хромосомные мутации – фрагменты и кольцевые хромосомы. Обсуждается возможная адаптивная роль присутствия В-хромосом у видов Picea.Проведено дослідження В-хромосом, виявлених вперше у виду Picea abies (L.) H. Karst. Для даного дослідження насіння зібране з двох популяцій Picea abies в Західних Родопах (Болгария), що розташовані на південному кордоні видового ареалу та охороняються відповідно до Бернської конвенції та Директивою ЄС про місце розповсюдження. В окремих проростках насіння Picea abies знайдено міксоплоїдію. Виявлено, що метафазні клітини проростків насіння з вивчених популяцій Picea abies містять 0–4 В-хромосоми як метацентричного, так і субметацентричного типів. Спостерігається мінливість числа В-хромосом. Поряд з В-хромосомами у метафазних клітинах Picea abies виявлено хромосомні мутації – фрагменти та кільцеві хромосоми. Обговорюється можлива адаптивна роль присутності В-хромосом у видів Picea

Atoll Archaeology in the Pacific

As islands formed by biogenic agents (unconsolidated carbonate sediments deposited by waves on reef platforms), atolls and table reefs, or low coral islands without lagoons, can be regarded as especially constraining habitats for human settlement. The challenges faced by people, both past and present, include low soil fertility, absence of perennial surface freshwater, and extreme vulnerability to flooding by stormsurge and sea-level rise due to low elevation of the highly fragmented landmass, only a few meters above mean sea level. There are about 300 atolls and low coral islands in the Pacific and thousands of individual islets (motu). Several archipelagoes are dominated by these limestone islands, such as the Tuamotus, the Central and Eastern Carolines, the Marshall Islands, Kiribati, and Tuvalu. Because of their small size, limited and at time fluctuating resources, and relative isolation, atolls are often perceived as marginal environments. While some human communities did not endure (Di Piazza and Pearthree 2001), a remarkable number were sustainable for centuries, taking advantage of opportunities many atolls provided and indicating a long history of resilience to environmental variability (Fitzpatrick et al. 2016). Despite these achievements, atolls have received relatively little coverage by Pacific archaeologist