Land use and dingo baiting are correlated with the density of kangaroos in rangeland systems.

Rangelands worldwide have been subject to broadscale modification, such as widespread predator control, introduction of permanent livestock water and altered vegetation to improve grazing. In Australia, these landscape changes have resulted in kangaroos (i.e. large macropods) populations increasing over the past 200 years. Kangaroos are a key contributor to total grazing pressure and in conjunction with livestock and feral herbivores have been linked to land degradation. We used 22 years of aerial survey data to investigate whether the density of 3 macropod species in the southern rangelands of Western Australia was associated with: (i) land use, including type of livestock, total livestock, density of feral goats, type of land tenure, and kangaroo commercial harvest effort; (ii) predator management, including permitted dingo control effort, estimated dingo abundance, and presence of the State Barrier Fence (a dingo exclusion fence); and (iii) environmental variables: ruggedness, rainfall, fractional cover, and total standing dry matter. Red kangaroos (Osphranter rufus) were most abundant in flat, open vegetation, on pastoral land, where area permitted for dingo control was high, and numbers were positively associated with antecedent rainfall with a 12-month delay. Western grey kangaroos (Macropus fuliginosus) were most abundant on flat, agricultural land, but less abundant in areas with high permitted dingo control. Euros (Osphranter robustus) were most abundant in rugged pastoral land with open vegetation, where permitted dingo control was high. While environmental variables are key drivers of landscape productivity and kangaroo populations, anthropogenic factors such as land use and permitted dingo control are strongly associated with kangaroo abundance.

Decadal abundance patterns in an isolated urban reptile assemblage: Monitoring under a changing climate.

Determine seasonal, annual, and decadal patterns of abundance in reptile species and assemblages occupying central Bold Park (~338 ha), an isolated urban bushland remnant in Perth, Southwestern Australia. Fenced pitfall trapping in four sampling sites, representing different habitats and fire history, over the primary reptile activity period for 35 consecutive years with over 17,000 individuals captured during 3300 days of sampling; the trapping regime was modified for the last 28 years. Sampling occurred in one of 35 global biodiversity hotspots that has a Mediterranean climate experiencing a 15% decline from the century average rainfall over the last 50 years. Twenty-nine species were recorded, with 16 captured in 32 or more years and accounting for nearly 97% of all captures; the six most common for 81%. Three taxa became locally extinct. Activity predominates in warmer and dryer months (October to April), peaking in November-December. Species richness remained relatively constant between years with around 73% of known taxa captured annually. Assemblages did not change when analyzing the presence/absence data but moved through five statistically significant assemblages analyzing relative abundance data. Over the last 28 years, relative abundance was significantly and positively correlated with annual rainfall residuals, uniquely for the 4 years preceding annual sampling, resulting in significant changes in total assemblages and significantly similar patterns in four sample sites; the presence/absence data indicated only minor assemblage changes across sites. The number of species recorded annually remained relatively constant, but relative abundance illustrated significant temporal changes in assemblages over decades. The modeled relationship between relative abundance and annual rainfall residuals for 4 years preceding annual sampling is supported by known ecological responses and reptile demographics within this Mediterranean climate. Maintenance of urban biodiversity should consider impacts of a significantly drying climate exacerbating the extinction debt already inherent in isolated bushland populations experiencing limited immigration.

Post-Release Monitoring of Western Grey Kangaroos (Macropus fuliginosus) Relocated from an Urban Development Site.

The expansion of urban areas and associated clearing of habitat can have severe consequences for native wildlife. One option for managing wildlife in these situations is to relocate them. While there is a general perception that relocation is humane, transparency of outcomes is lacking. Here, we document the outcome of 122 western grey kangaroos (Macropus fuliginosus) relocated from an urban development site on the edge of Perth, Western Australia. Global Positioning System (GPS) or Very High Frequency (VHF) collars were fitted to 67 kangaroos, and their survival and movement were monitored over 12 months using telemetry, camera traps and spotlighting. Only six collared animals survived for the duration of the study with most dying within a week of the relocation, indicating stress associated with capture as the likely cause. By the completion of the study, 111 kangaroos were predicted to have died based on the proportion of individuals known to have died. Movement patterns of surviving GPS collared kangaroos changed over time from largely exploratory forays, to more repeated movements between focus areas within home ranges. The poor outcome here raises concerns around the viability of relocating a relatively large number of kangaroos as a management option. It also highlights the need for careful planning to limit the stress associated with capture and transport if relocations are to be used for managing kangaroos in urban areas.

Lung Cancer Screening in Patients with COPD-A Case Report.

We present two cases demonstrating the nuances that must be considered when determining if a patient could benefit from low dose computed tomography (LDCT) lung cancer screening. Our case report discusses the available literature, where it exists, on lung cancer screening with special attention to the impact of chronic obstructive pulmonary disease (COPD), and poor functional status. Patients with COPD and concurrent smoking history are at higher risk of lung cancer and may therefore benefit from lung cancer screening. However, this population is at increased risk for complications related to biopsies and lobar resections. Appropriate interventions other than surgical resection exist for COPD patients with poor pulmonary reserve. Risks and benefits of lung cancer screening are unique to each patient and require shared decision-making.

Is genomic diversity a useful proxy for census population size? Evidence from a species-rich community of desert lizards.

Species abundance data are critical for testing ecological theory, but obtaining accurate empirical estimates for many taxa is challenging. Proxies for species abundance can help researchers circumvent time and cost constraints that are prohibitive for long-term sampling. Under simple demographic models, genetic diversity is expected to correlate with census size, such that genome-wide heterozygosity may provide a surrogate measure of species abundance. We tested whether nucleotide diversity is correlated with long-term estimates of abundance, occupancy and degree of ecological specialization in a diverse lizard community from arid Australia. Using targeted sequence capture, we obtained estimates of genomic diversity from 30 species of lizards, recovering an average of 5,066 loci covering 3.6 Mb of DNA sequence per individual. We compared measures of individual heterozygosity to a metric of habitat specialization to investigate whether ecological preference exerts a measurable effect on genetic diversity. We find that heterozygosity is significantly correlated with species abundance and occupancy, but not habitat specialization. Demonstrating the power of genomic sampling, the correlation between heterozygosity and abundance/occupancy emerged from considering just one or two individuals per species. However, genetic diversity does no better at predicting abundance than a single day of traditional sampling in this community. We conclude that genetic diversity is a useful proxy for regional-scale species abundance and occupancy, but a large amount of unexplained variation in heterozygosity suggests additional constraints or a failure of ecological sampling to adequately capture variation in true population size.

Stable isotope ecology of a hyper-diverse community of scincid lizards from arid Australia.

We assessed the utility of stable isotope analysis as a tool for understanding community ecological structure in a species-rich clade of scincid lizards from one of the world's most diverse lizard communities. Using a phylogenetic comparative framework, we tested whether δ15N and δ13C isotopic composition from individual lizards was correlated with species-specific estimates of diet and habitat use. We find that species are highly divergent in isotopic composition with significant correlations to habitat use, but this relationship shows no phylogenetic signal. Isotopic composition corresponds to empirical observations of diet for some species but much variation remains unexplained. We demonstrate the importance of using a multianalytical approach to questions of long-term dietary preference, and suggest that the use of stable isotopes in combination with stomach content analysis and empirical data on habitat use can potentially reveal patterns in ecological traits at finer scales with important implications for community structuring.

Activation of heat shock response augments fibroblast growth factor-1 expression in wounded lung epithelium.

We previously showed that coincident exposure to heat shock (HS; 42°C for 2 h) and TNF-α synergistically induces apoptosis in mouse lung epithelium. We extended this work by analyzing HS effects on human lung epithelial responses to clinically relevant injury. Cotreatment with TNF-α and HS induced little caspase-3 and poly(ADP-ribose) polymerase cleavage in human small airway epithelial cells, A549 cells, and BEAS2B cells. Scratch wound closure rates almost doubled when A549 and BEAS2B cells and air-liquid interface cultures of human bronchial epithelial cells were heat shocked immediately after wounding. Microarray, qRT-PCR, and immunoblotting showed fibroblast growth factor 1 (FGF1) to be synergistically induced by HS and wounding. Enhanced FGF1 expression in HS/wounded A549 was blocked by inhibitors of p38 MAPK (SB203580) or HS factor (HSF)-1 (KNK-437) and in HSF1 knockout BEAS2B cells. PCR demonstrated FGF1 to be expressed from the two most distal promoters in wounded/HS cells. Wound closure in HS A549 and BEAS2B cells was reduced by FGF receptor-1/3 inhibition (SU-5402) or FGF1 depletion. Exogenous FGF1 accelerated A549 wound closure in the absence but not presence of HS. In the presence of exogenous FGF1, HS slowed wound closure, suggesting that it increases FGF1 expression but impairs FGF1-stimulated wound closure. Frozen sections from normal and idiopathic pulmonary fibrosis (IPF) lung were analyzed for FGF1 and HSP70 by immunofluorescence confocal microscopy and qRT-PCR. FGF1 and HSP70 mRNA levels were 7.5- and 5.9-fold higher in IPF than normal lung, and the proteins colocalized to fibroblastic foci in IPF lung. We conclude that HS signaling may have an important impact on gene expression contributing to lung injury, healing, and fibrosis.

Septicemia and Aortic Valve Endocarditis due to Erysipelothrix rhusiopathiae in a Homeless Man.

We report a case of bacterial endocarditis due to Erysipelothrix rhusiopathiae in a homeless man with no animal exposure. His course was complicated by an allergic reaction to ampicillin, urinary bladder infection, respiratory failure, and acute kidney injury. He recovered completely after aortic valve replacement and a 6-week course of intravenous ceftriaxone.

A 32-Year-Old Female with AIDS, Pneumocystis jiroveci Pneumonia, and Methemoglobinemia.

We report a case of methemoglobinemia with significant hemoglobin desaturation in a young female with AIDS who was being treated for Pneumocystis jiroveci pneumonia. A review of the etiology, pathophysiology, and treatment of methemoglobinemia is presented.

Nonpharmacologic approach to minimizing shivering during surface cooling: a proof of principle study.

PURPOSE: This study had 2 objectives: (1) to quantify the metabolic response to physical cooling in febrile patients with systemic inflammatory response syndrome (SIRS) and (2) to provide proof for the hypothesis that the efficiency of external cooling and the subsequent shivering response are influenced by site and temperature of surface cooling pads. METHODS: To quantify shivering thermogenesis during surface cooling for fever, we monitored oxygen consumption (VO(2)) in 6 febrile patients with SIRS during conventional cooling with cooling blankets and ice packs. To begin to determine how location and temperature of surface cooling influence shivering, we compared 5 cooling protocols for inducing mild hypothermia in 6 healthy volunteers. RESULTS: In the patients with SIRS, core temperature decreased 0.67 °C per hour, all patients shivered, VO(2) increased 57.6%, and blood pressure increased 15% during cooling. In healthy subjects, cooling with the 10 °C vest was most comfortable and removed heat most efficiently without shivering or VO(2) increase. Cooling with combined vest and thigh pads stimulated the most shivering and highest VO(2) and increased core temperature. Reducing vest temperature from 10 °C to 5 °C failed to increase heat removal secondary to cutaneous vasoconstriction. Capsaicin, an agonist for the transient receptor potential cation channel subfamily V member 1 (TRPV1) warm-sensing channels, partially reversed this effect in 5 subjects. CONCLUSIONS: Our results identify the hazards of surface cooling in febrile critically ill patients and support the concept that optimization of cooling pad temperature and position may improve cooling efficiency and reduce shivering.

Species interactions mediate phylogenetic community structure in a hyperdiverse lizard assemblage from arid Australia.

Evolutionary history can exert a profound influence on ecological communities, but few generalities have emerged concerning the relationships among phylogeny, community membership, and niche evolution. We compared phylogenetic community structure and niche evolution in three lizard clades (Ctenotus skinks, agamids, and diplodactyline geckos) from arid Australia. We surveyed lizard communities at 32 sites in the northwestern Great Victoria Desert and generated complete species-level molecular phylogenies for regional representatives of the three clades. We document a striking pattern of phylogenetic evenness within local communities for all groups: pairwise correlations in species abundance across sites are negatively related to phylogenetic similarity. By modeling site suitability on the basis of species' habitat preferences, we demonstrate that phylogenetic evenness generally persists even after controlling for habitat filtering among species. This phylogenetic evenness is coupled with evolutionary lability of habitat-associated traits, to the extent that closely related species are more divergent in habitat use than distantly related species. In contrast, lizard diets are phylogenetically conserved, and pairwise dietary overlap between species is negatively related to phylogenetic distance in two of the three clades. Our results suggest that contemporary and historical species interactions have led to similar patterns of community structure across multiple clades in one of the world's most diverse lizard communities.

The type I NADH dehydrogenase of Mycobacterium tuberculosis counters phagosomal NOX2 activity to inhibit TNF-alpha-mediated host cell apoptosis.

The capacity of infected cells to undergo apoptosis upon insult with a pathogen is an ancient innate immune defense mechanism. Consequently, the ability of persisting, intracellular pathogens such as the human pathogen Mycobacterium tuberculosis (Mtb) to inhibit infection-induced apoptosis of macrophages is important for virulence. The nuoG gene of Mtb, which encodes the NuoG subunit of the type I NADH dehydrogenase, NDH-1, is important in Mtb-mediated inhibition of host macrophage apoptosis, but the molecular mechanism of this host pathogen interaction remains elusive. Here we show that the apoptogenic phenotype of MtbDeltanuoG was significantly reduced in human macrophages treated with caspase-3 and -8 inhibitors, TNF-alpha-neutralizing antibodies, and also after infection of murine TNF(-/-) macrophages. Interestingly, incubation of macrophages with inhibitors of reactive oxygen species (ROS) reduced not only the apoptosis induced by the nuoG mutant, but also its capacity to increase macrophage TNF-alpha secretion. The MtbDeltanuoG phagosomes showed increased ROS levels compared to Mtb phagosomes in primary murine and human alveolar macrophages. The increase in MtbDeltanuoG induced ROS and apoptosis was abolished in NOX-2 deficient (gp91(-/-)) macrophages. These results suggest that Mtb, via a NuoG-dependent mechanism, can neutralize NOX2-derived ROS in order to inhibit TNF-alpha-mediated host cell apoptosis. Consistently, an Mtb mutant deficient in secreted catalase induced increases in phagosomal ROS and host cell apoptosis, both of which were dependent upon macrophage NOX-2 activity. In conclusion, these results serendipitously reveal a novel connection between NOX2 activity, phagosomal ROS, and TNF-alpha signaling during infection-induced apoptosis in macrophages. Furthermore, our study reveals a novel function of NOX2 activity in innate immunity beyond the initial respiratory burst, which is the sensing of persistent intracellular pathogens and subsequent induction of host cell apoptosis as a second line of defense.

Prostaglandin E2 potentiates heat shock-induced heat shock protein 72 expression in A549 cells.

The heat shock (HS) response is an important cytoprotective response comprising the expression of heat shock proteins (HSPs) and orchestrated by the heat/stress-induced transcription factor, heat shock factor-1 (HSF-1). Previous studies suggest that the activation threshold and magnitude of the HS response may be modified by treatment with arachidonic acid (AA). We analyzed the effect of exogenous AA and its metabolites, PGE(2), LTD(4), and 15-HETE on HSF-1-dependent gene expression in A549 human respiratory epithelial-like cells. When added at 1microM, PGE(2) much more than LTD(4), but not 15-HETE increased activity of a synthetic HSF-1-dependent reporter after HS exposure (42 degrees C for 2h), but had no effect in the absence of HS. Exposing A549 cells to HS stimulated the release of PGE(2) and treatment with the cyclooxygenase inhibitor, ibuprofen, reduced HS-induced HSF-1-dependent transcription. PGE(2) increased HS-induced HSP72 mRNA and protein expression but EMSA and Western blot analysis failed to show an effect on HSF-1 DNA binding activity or post-translational modification. In summary, we showed that HS stimulates the generation of PGE(2), which augments the generation of HSPs. The clinical consequences of this pathway have yet to be determined.

Core temperature correlates with expression of selected stress and immunomodulatory genes in febrile patients with sepsis and noninfectious SIRS.

Environmental hyperthermia and exercise produce extensive changes in gene expression in human blood cells, but it is unknown whether this also happens during febrile-range hyperthermia. We tested the hypothesis that heat shock protein (HSP) and immunomodulatory stress gene expression correlate with fever in intensive care unit patients. Whole blood messenger RNA was obtained over consecutive days from 100 hospitalized patients suffering from sepsis or noninfectious systemic inflammatory response syndrome (SIRS) as defined by conventional criteria. The most abnormal body temperature in the preceding 24 h was recorded for each sample. Expression analysis was performed using the Affymetrix U133 chip. ANCOVA followed by correlation analysis was performed on a subset of 278 prospectively identified sequences of interest. Temperature affected expression of 60 sequences, either independently or as a function of clinical diagnosis. Forty-eight of these (representing 38 genes) were affected by temperature only, including several HSPs, transcription factors heat shock factor (HSF)-1 and HSF-4, cellular adhesion molecules such as ICAM1/CD54 and JAM3, toll receptors TLR-6 and TLR-7, ribosomal proteins, and a number of molecules involved in inflammatory pathways. Twelve sequences demonstrated temperature-dependent responses that differed significantly between patients with sepsis and noninfectious SIRS: CXCL-13; heat shock proteins DNAJB12 and DNAJC4; the F11 receptor; folate hydrolase 1; HSF-2; HSP 70 proteins HSPA1A, HSPA1B, and HSPA1L; interleukin 8; lipopolysaccharide binding protein; and prostaglandin E synthase. Febrile-range temperatures achieved during sepsis and noninfectious SIRS correlate with detectable changes in stress gene expression in vivo, suggesting that fever can activate HSP gene expression and modify innate immune responses. For some genes, it appears that clinical condition can alter temperature-sensitive gene expression. Collectively, these data underscore the potential importance of body temperature in shaping the immune response to infection and injury.

Tobacco smoking inhibits expression of proinflammatory cytokines and activation of IL-1R-associated kinase, p38, and NF-kappaB in alveolar macrophages stimulated with TLR2 and TLR4 agonists.

Tobacco smoking has been associated with impaired pulmonary functions and increased incidence of infections; however, mechanisms that underlie these phenomena are poorly understood. In this study, we examined whether smokers' alveolar macrophages (AM) exhibit impaired sensing of bacterial components via TLR2 and TLR4 and determined the effect of smoking on expression levels of TLR2, TLR4 and coreceptors, and activation of signaling intermediates. Smokers' AMs exhibited reduced gene expression and secretion of proinflammatory cytokines (TNF-alpha, IL-1beta, IL-6) and chemokines (RANTES and IL-8) upon stimulation with TLR2 and TLR4 agonists, S-[2,3-bis(palmitoyloxy)-(2-RS)-propyl]-N-palmitoyl-(R)-Cys-(S)-Ser-Lys4-OH trihydrochloride (Pam(3)Cys), and LPS, whereas expression of anti-inflammatory cytokines (IL-10 and IL-1 receptor antagonist) was not affected. TLR3 activation with polyinosinic-polycytidylic acid led to comparable or even higher cytokine responses in smokers' AMs, indicating that smoking-induced suppression does not affect all TLRs. Comparable expression of cytokines and chemokines was detected in PBMC and purified monocytes obtained from smokers and nonsmokers, demonstrating that the suppressive effect of smoking is restricted to the lung. TLR2/4-inducible IL-1R-associated kinase-1 (IRAK-1) and p38 phosphorylation and NF-kappaB activation was suppressed in smokers' AMs, whereas TLR2, TLR4, CD14, MD-2 mRNA levels, and TLR4 protein expression were not altered. These data suggest that changes in expression and/or activities of signaling intermediates at the postreceptor level account for smoking-induced immunosuppression. Thus, exposure of AMs to tobacco smoke induces a hyporesponsive state similar to endotoxin tolerance as manifested by inhibited TLR2/4-induced expression of proinflammatory cytokines, chemokines, and impaired activation of IRAK-1, p38, and NF-kappaB, resulting in suppressed expression of proinflammatory mediators.

Overdispersion of body size in Australian desert lizard communities at local scales only: no evidence for the Narcissus effect.

Both local and regional processes may contribute to community diversity and structure at local scales. Although many studies have investigated patterns of local or regional community structure, few have addressed the extent to which local community structure influences patterns within regional species pools. Here we investigate the role of body size in community assembly at local and regional scales in Ctenotus lizards from arid Australia. Ctenotus has long been noted for its exceptional species diversity in the Australian arid-zone, and previous studies have attempted to elucidate the processes underlying species coexistence within communities of these lizards. However, no consensus has emerged on the role of interspecific competition in the assembly and maintenance of Ctenotus communities. We studied Ctenotus communities at several hundred sites in the arid interior of Australia to test the hypothesis that body sizes within local and regional Ctenotus assemblages should be overdispersed relative to null models of community assembly, and we explored the relationship between body size dispersion at local and regional scales. Results indicate a striking pattern of community-wide overdispersion of body size at local scales, as measured by the variance in size ratios among co-occurring species. However, we find no evidence for body size overdispersion within regional species pools, suggesting a lack of correspondence between processes influencing the distribution of species phenotypes at local and regional scales. We suggest that size ratio constancy in Ctenotus communities may have resulted from contemporary ecological interactions among species or ecological character displacement, and we discuss alternative explanations for the observed patterns.

Severe metabolic alkalosis due to pyloric obstruction: case presentation, evaluation, and management.

A 46-year-old man presented to the emergency room with severe metabolic alkalosis, hypokalemia, and respiratory failure requiring intubation and mechanical ventilation. The cause of his acid-base disorder was initially unclear. Although alkalosis is common in the intensive care unit, metabolic alkalosis of this severity is unusual, carries a very high mortality rate, and requires careful attention to the pathophysiology and differential diagnosis to effectively evaluate and treat the patient. A central concept in the diagnosis of metabolic alkalosis is distinguishing chloride responsive and chloride nonresponsive states. Further studies are then guided by the history and physical examination in most cases. By using a systematic approach to the differential diagnosis, we were able to determine that a high-grade gastric outlet obstruction was the cause of the patients' alkalosis and to offer effective therapy for his condition. A literature review and algorithm for the diagnosis and management of metabolic alkalosis are also presented.

Feasibility and safety of a novel technology for pacing without leads.

BACKGROUND: Pacemaker lead complications and failures remain clinical problems. New devices incorporating three leads are associated with even greater limitations. OBJECTIVES: The purpose of this study was to investigate the feasibility and safety of a technology enabling cardiac pacing without leads in an acute porcine model. METHODS: The system is composed of an ultrasound transmitter delivering energy from the chest wall to a receiver-electrode in contact with the myocardium that then converts the ultrasound energy to electrical energy sufficient to pace. In five feasibility studies, the receiver-electrodes were attached to the tip of a catheter to facilitate intracardiac positioning at pacing sites. In six safety studies (five treatment and one sham), ultrasound energy was transmitted to both chest walls, and histopathologic examinations were performed to evaluate bioeffects due to ultrasound energy transmission. RESULTS: In five feasibility studies, direct and ultrasound-mediated electrical pacing was demonstrated at 30 sites in the right atrium, right ventricle, and left ventricle, at direct electrical pacing outputs of 1.4 +/- 0.6 V and ultrasound-mediated electrical pacing outputs of 1.8 +/- 0.9 V. The mechanical index was 0.6 +/- 0.4 at the receiver site during ultrasound-mediated pacing at a depth of 11.2 +/- 2.4 cm from the chest wall. Using two receiver-electrode catheters, biventricular pacing was demonstrated in all studies. In five safety study treatment animals at a similar depth, the peak mechanical index was 2.3, and the thermal index was 0.4. Microscopic evaluation revealed no evidence of mechanical or thermal bioeffects. CONCLUSION: The feasibility and safety of this novel technology for pacing without leads has been demonstrated acutely in animals.

Polyamine-mediated reduction in human airway epithelial migration in response to wounding is PGE2 dependent through decreases in COX-2 and cPLA2 protein levels.

Both ornithine decarboxylase inhibition to deplete polyamines and cyclooxygenase inhibition diminish the migration response to injury of human airway epithelial cells in tissue culture monolayers by approximately 75%. Restoration of normal migration responses is achieved in the polyamine depleted system either by exogenous reconstitution of polyamines or the addition of prostaglandin E(2) (PGE(2)). However, only PGE(2) was able to restore migration in the cyclooxygenase-inhibited systems. Western blot for cyclooxygenase-2 and cytosolic phospholipase A(2) protein levels and ELISAs for PGE(2) secretion demonstrate dramatic increases over 24-48 h after monolayer wounding. These increases are completely abolished by polyamine depletion or cyclooxygenase inhibition. We conclude that polyamine inhibition decreases cellular migration in response to injury in airway epithelial cells at least in part through inhibiting normal PGE(2) production in response to injury. This may be brought about by decreases in cytosolic phospholipase A(2) and cyclooxygenase-2 protein levels.

The role of TFIID, the initiator element and a novel 5' TFIID binding site in the transcriptional control of the TATA-less human cytosolic phospholipase A2-alpha promoter.

Human cytosolic phospholipase A2-alpha (cPLA2-alpha) is a critical enzyme in the liberation of arachidonic acid (AA) from cellular membranes and the subsequent formation of prostaglandins (PGs), leukotrienes (LTs), hydroxyeicosatetraenoic acids (HETEs) and platelet activating factor in many different cell types. Much is known of the effect of posttranslational phosphorylation and calcium binding events on the enzymatic activity of cPLA2-alpha, but to date little is known about its specific transcriptional control. Through the use of reporter gene constructs and eletrophoretic mobility shift assays (EMSAs), this study determined the minimal promoter required for basal transcriptional activity of the human cPLA2-alpha promoter to include base pairs -40 through the transcription start site (TSS). In addition, it confirms the importance of an initiator (Inr) element at the TSS by deletion reporter gene analysis, and further identifies bases -3 (C) and -2 (T) as critical bases in the Inr function by mutation reporter gene analysis. Finally, this study describes a novel AAGGAG motif at -30 to -35 which is bound by TATA-box binding protein (TBP) and is critical for basal transcriptional activity.