To better understand the olfactory mechanisms in the two lepidopteran pest model species, the Helicoverpa armigera and H. assulta, we conducted transcriptome analysis of the adult antennae using Illumina sequencing technology and compared the chemosensory genes between these two related species. Combined with the chemosensory genes we had identified previously in H. armigera by 454 sequencing, we identified 133 putative chemosensory unigenes in H. armigera including 60 odorant receptors (ORs), 19 ionotropic receptors (IRs), 34 odorant binding proteins (OBPs), 18 chemosensory proteins (CSPs), and 2 sensory neuron membrane proteins (SNMPs). Consistent with these results, 131 putative chemosensory genes including 64 ORs, 19 IRs, 29 OBPs, 17 CSPs, and 2 SNMPs were identified through male and female antennal transcriptome analysis in H. assulta. Reverse Transcription-PCR (RT-PCR) was conducted in H. assulta to examine the accuracy of the assembly and annotation of the transcriptome and the expression profile of these unigenes in different tissues. Most of the ORs, IRs and OBPs were enriched in adult antennae, while almost all the CSPs were expressed in antennae as well as legs. We compared the differences of the chemosensory genes between these two species in detail. Our work will surely provide valuable information for further functional studies of pheromones and host volatile recognition genes in these two related species.
Extensive surveillance of influenza A viruses in different avian species is critical for understanding its transmission. Here, a breeding colony of Little Egrets and Black-crowned Night Herons was monitored both serologically and virologically in a city park of Jiangxi in 2009. A portion of herons had antibodies against H7 (52%), H5 (55%) and H9 (6%) subtype avian influenza virus (AIV) in egg yolk samples, and 45% had antibodies against different AIV serotypes (H5, H7 or H9) simultaneously. Greater numbers of samples with anti-AIV H5N1 recombination-4 (Re-4, clade 7) antibodies were measured compared with those containing anti-H5N1 Re-1 (clade 0) and Re-5 (clade 2.3.4) antibodies. Eight strains of H5 and 9 strains of H9 were isolated from poultry of nearby markets. These results indicate wild birds are at risk from infection and co-infection with H7, H5, and H9 subtypes. Investigation of wild bird infection might provide an early warning sign of potential novel AIVs circulating in the nearby poultry industry and even in human society.
The cotton aphid, Aphis gossypii Glover, is a polyphagous pest that inflicts great damage to cotton yields worldwide. Antennal olfaction, which is extremely important for insect survival, mediates key behaviors such as host preference, mate choice, and oviposition site selection. In insects, odor detection is mediated by odorant receptors (ORs) and ionotropic receptors (IRs), which ensure the specificity of the olfactory sensory neuron responses. In this study, our aim is to identify chemosensory receptors in the cotton aphid genome, as a means to uncover olfactory encoding of the polyphagous feeding habits as well as to aid the discovery of new targets for behavioral interference. We identified a total of 45 candidate ORs and 14 IRs in the cotton aphid genome. Among the candidate AgoORs, 9 are apparent pseudogenes, while 19 can be clustered with ORs from the pea aphid, forming 16 AgoOR/ApOR orthologous subgroups. Among the candidate IRs, we identified homologs of the two highly conserved co-receptors IR8a and IR25a; no AgoIR retain the complete glutamic acid binding domain, suggesting that putative AgoIRs bind different ligands. Our results provide the necessary information for functional characterization of the chemosensory receptors of A. gossypii, with potential for new or refined applications of semiochemicals-based control of this pest insect.
Surfactant protein A (SP-A) plays a number of roles in lung host defense and innate immunity. There are two human genes, SFTPA1 and SFTPA2, and evidence indicates that the function of SP-A1 and SP-A2 proteins differ in several respects. To investigate the impact of SP-A1 and SP-A2 on the alveolar macrophage (AM) phenotype, we generated humanized transgenic (hTG) mice on the SP-A knockout (KO) background, each expressing human SP-A1 or SP-A2. Using two-dimensional difference gel electrophoresis (2D-DIGE) we studied the AM cellular proteome. We compared mouse lines expressing high levels of SPA1, high levels of SP-A2, low levels of SP-A1, and low levels of SP-A2, with wild type (WT) and SP-A KO mice. AM from mice expressing high levels of SP-A2 were the most similar to WT mice, particularly for proteins related to actin and the cytoskeleton, as well as proteins regulated by Nrf2. The expression patterns from mouse lines expressing higher levels of the transgenes were almost the inverse of one another – the most highly expressed proteins in SP-A2 exhibited the lowest levels in the SP-A1 mice and vice versa. The mouse lines where each expressed low levels of SP-A1 or SP-A2 transgene had very similar protein expression patterns suggesting that responses to low levels of SP-A are independent of SP-A genotype, whereas the responses to higher amounts of SP-A are genotype-dependent. Together these observations indicate that in vivo exposure to SP-A1 or SP-A2 differentially affects the proteomic expression of AMs, with SP-A2 being more similar to WT.
surfactant; lung; 2D-DIGE; collectin; host defense
In this study, we first generated and characterized a polyclonal antibody against unique domain of matrlin-2 and then used this specific antibody to assess the expression pattern of matrilin-2 by immunohistochemistry. We found that marilin-2 is widely distributed in the connective tissues of many mouse tissues including heart, colon, penis, esophagus, lung, kidney, tracheal cartilage, developmental bone, and adult bone. The expression level of matrilin-2 was remarkably increased in the tissues of osteoarthritis developmental articular cartilage, compared to normal healthy tissues. Furthermore, we determined matrilin-2 expression in specific epithelial cells in stomach and ductal epithelial cells of salivary gland. In other tissues, the positive signals were mainly located around cardiac muscle cells and Purkinje fibers in the heart; corpus spongiosum in the penis; submucosa in the colon and esophagus; extracellular matrix of cartilage in the tracheal cartilage; and, glomerulus, the basement membrane of distal convoluted tubule and renal matrix in kidney. These observations indicated that the distribution pattern of matrilin-2 is heterogeneous in each tissue. Matrilin-2 may play an important role in the communication of matrix to matrix and matrix to cells and will be used as a potential biomarker in the early stage of osteoarthritis of articular cartilage.
The Asian corn borer (Ostrinia furnacalis (Guenée)) is one of the most serious corn pests in Asia. Control of this pest with entomopathogenic fungus Beauveria bassiana has been proposed. However, the molecular mechanisms involved in the interactions between O. furnacalis and B. bassiana are unclear, especially under the conditions that the genomic information of O. furnacalis is currently unavailable. So we sequenced and characterized the transcriptome of O. furnacalis larvae infected by B. bassiana with special emphasis on immunity-related genes.
Illumina Hiseq2000 was used to sequence 4.64 and 4.72 Gb of the transcriptome from water-injected and B. bassiana-injected O. furnacalis larvae, respectively. De novo assembly generated 62,382 unigenes with mean length of 729 nt. All unigenes were searched against Nt, Nr, Swiss-Prot, COG, and KEGG databases for annotations using BLASTN or BLASTX algorithm with an E-value cut-off of 10−5. A total of 35,700 (57.2%) unigenes were annotated to at least one database. Pairwise comparisons resulted in 13,890 differentially expressed genes, with 5,843 up-regulated and 8,047 down-regulated. Based on sequence similarity to homologs known to participate in immune responses, we totally identified 190 potential immunity-related unigenes. They encode 45 pattern recognition proteins, 33 modulation proteins involved in the prophenoloxidase activation cascade, 46 signal transduction molecules, and 66 immune responsive effectors, respectively. The obtained transcriptome contains putative orthologs for nearly all components of the Toll, Imd, and JAK/STAT pathways. We randomly selected 24 immunity-related unigenes and investigated their expression profiles using quantitative RT-PCR assay. The results revealed variant expression patterns in response to the infection of B. bassiana.
This study provides the comprehensive sequence resource and expression profiles of the immunity-related genes of O. furnacalis. The obtained data gives an insight into better understanding the molecular mechanisms of innate immune processes in O. furnacalis larvae against B. bassiana.
The abscopal effect has previously been described in various tumors and is associated with radiation therapy and hyperthermia, with possible underlying mechanisms explaining each observed case. In the present study, we aimed to investigate the antitumor effects of magnet-mediated hyperthermia on Walker-256 carcinosarcomas in rats at two different temperature ranges (42–46°C and 50–55°C). We also aimed to identify whether a higher therapeutic temperature of magnetic-mediated hyperthermia improves the abscopal antitumor effects, where localised irradiation of the tumor causes not only the irradiated tumor to shrink, but also tumors located far from the area of irradiation. Following induction of carcinosarcoma in both sides of the body, magnet-mediated hyperthermia was applied to one side only, leaving the other side as a control. The changes in tumor growth were observed. Our results demonstrated that magnet-mediated hyperthermia at a higher temperature inhibited the growth of carcinosarcoma at the site of treatment. Furthermore, the growth of the carcinosarcoma on the untreated side was also inhibited. The expression levels of proliferating cell nuclear antigen were decreased in the hyperthermia group, which was more significant in the higher temperature test group. Flow cytometric analysis showed an increased number of CD4- and CD8-positive T cells, and enzyme-linked immunosorbent assay showed increased levels of interferon-γ and interleukin-2 in the higher temperature group. These results suggested that magnet-mediated hyperthermia at a higher temperature (50–55°C) can improve the abscopal antitumor effects and stimulate a greater endogenous immune response in carcinosarcoma-bearing rats.
magnet-mediated hyperthermia; abscopal effect; temperature; Walker-256 carcinosarcoma; tumor immunity
Antennal olfaction, which is extremely important for insect survival, mediates key behaviors such as host preference, mate choice, and oviposition site selection. In insects, odor detection is mediated by multiple proteins in the antenna, especially the odorant receptors (ORs) and ionotropic receptors (IRs), which ensure the specificity of the olfactory sensory neuron responses. In this study, we identified the olfactory gene repertoire of the rice stem borer, Chilo suppressalis, an economically important agricultural pest, which inflicts great damage to the rice yield in south and east part of Asia, especially in Southern China. By Illumina sequencing of male and female antennal transcriptomes, we identified 47 odorant receptors, 20 ionotropic receptors, 26 odorant binding proteins, 21 chemosensory proteins and 2 sensory neuron membrane proteins. Our findings make it possible for future research of the olfactory system of C. suppressalis at the molecular level.
C. suppressali; antennal olfaction; olfactory gene
The timely differentiation of Mycobacterium tuberculosis complex (MTC) and non-tubercular mycobacterium (NTM) species is urgently needed in patient care since the routine laboratory method is time consuming and cumbersome. An easy and cheap method which can successfully distinguish MTC from NTM was established and evaluated. 38 mycobacterial type and reference strains and 65 clinical isolates representing 10 species of mycobacterium were included in this study. Metabolites of p-nitrobenzoic acid (PNB) reduction were identified using liquid chromatography and tandem mass spectrometry (LC/MS/MS). A spectrophotometric method was developed to detect these metabolites, which was evaluated on a number of MTC and NTM species. All of the tested NTM species and strains reduced PNB to p-aminobenzoic acid (PABA), while none of the MTC strains showed a similar activity. Spectrophotometric detection of PABA had 100% sensitivity and specificity for MTC and NTM differentiation among the type strains and the clinical isolates tested. PABA was identified as one of the metabolites of PNB reduction. All the tested NTM species metabolized PNB to PABA whereas the MTC members lacked this activity. A simple, specific and cost-effective method based on PABA production was established in order to discriminate MTC from NTM from cultured organisms.
Established ARDS is often refractory to treatment. Clinical trials have demonstrated modest treatment effects, and mortality remains high. Ventilator strategies must be developed to prevent ARDS.
Early ventilatory intervention will block progression to ARDS if the ventilator mode: 1) maintains alveolar stability and 2) reduces pulmonary edema formation.
Yorkshire Pigs (38–45kg) were anaesthetized and subjected to "2-hit" Ischemia-Reperfusion and Peritoneal Sepsis. Following injury, animals were randomized into two groups: Early Preventative Ventilation (Airway Pressure Release Ventilation- APRV) vs. Non-Preventative Ventilation (NPV) and followed for 48hr. All animals received anesthesia, antibiotics, and fluid/vasopressor therapy per Surviving Sepsis Campaign. Ventilation parameters: 1) NPV Group - Tidal volume (Vt): 10cc/kg + PEEP- 5 cm/H2O volume-cycled mode, 2) APRV Group - Vt: 10–15 cc/kg; Phigh, Plow, Thigh, Tlow were titrated for optimal alveolar stability. Physiologic data and plasma were collected throughout the 48hr study period, followed by BAL and necropsy.
APRV prevented development of ARDS (p<0.001 vs NPV) by PaO2/FiO2 ratio. Quantitative histological scoring showed APRV prevented lung tissue injury (p<0.001 vs. NPV). BALF showed APRV lowered total protein and IL-6, while preserving surfactant proteins A & B (p<0.05 vs. NPV). APRV significantly lowered lung water (p<0.001 vs. NPV). Plasma IL-6 concentrations were similar between groups.
Early preventative mechanical ventilation with APRV blocked ARDS development, preserved surfactant proteins, and reduced pulmonary inflammation and edema, despite systemic inflammation similar to NPV. These data suggest early preventative ventilation strategies stabilizing alveoli and reducing pulmonary edema can attenuate ARDS after ischemia-reperfusion-sepsis.
Sepsis; Shock; ARDS; ALI; Ventilator Induced Lung Injury; Airway Pressure Release Ventilation
The first half of the surfactant protein B (SP-B) gene intron 4 is a CA-repeat-rich region that contains 11 motifs. To study the role of this region on SP-B mRNA splicing, minigenes were generated by systematic removal of motifs from either the 5′ or 3′ end. These were transfected in CHO cells to study their splicing efficiency. The latter was determined as the ratio of completely to incompletely spliced SP-B RNA. Our results indicate that SP-B intron 4 motifs differentially affect splicing. Motifs 8 and 9 significantly enhanced and reduced splicing of intron 4, respectively. RNA mobility shift assays performed with a Motif 8 sequence that contains a CAUC cis-element and cell extracts resulted in a RNA:protein shift that was lost upon mutation of the element. Furthermore, in silico analysis of mRNA secondary structure stability for minigenes with and without motif 8 indicated a correlation between mRNA stability and splicing ratio. We conclude that differential loss of specific intron 4 motifs results in one or more of the following: a) altered splicing, b) differences in RNA stability and c) changes in secondary structure. These, in turn, may affect SP-B content in lung health or disease.
Moths depend on olfactory cues such as sex pheromones to find and recognize mating partners. Pheromone receptors (PRs) and Pheromone binding proteins (PBPs) are thought to be associated with olfactory signal transduction of pheromonal compounds in peripheral olfactory reception. Here six candidate pheromone receptor genes in the diamondback moth, Plutella xyllostella were identified and cloned. All of the six candidate PR genes display male-biased expression, which is a typical characteristic of pheromone receptors. In the Xenopus-based functional study and in situ hybridization, PxylOR4 is defined as another pheromone receptor in addition to the previously characterized PxylOR1. In the study of interaction between PRs and PBPs, PxylPBPs could increase the sensitivity of the complex expressing oocyte cells to the ligand pheromone component while decreasing the sensitivity to pheromone analogs. We deduce that activating pheromone receptors in olfactory receptor neurons requires some role of PBPs to pheromone/PBP complex. If the chemical signal is not the pheromone component, but instead, a pheromone analog with a similar structure, the complex would have a decreased ability to activate downstream pheromone receptors.
Male moths can accurately perceive the sex pheromone emitted from conspecific females by their highly accurate and specific olfactory sensory system. Pheromone receptors are of special importance in moth pheromone reception because of their central role in chemosensory signal transduction processes that occur in olfactory receptor neurons in the male antennae. There are a number of pheromone receptor genes have been cloned, however, only a few have been functionally characterized. Here we cloned six full-length pheromone receptor genes from Helicoverpa armigera male antennae. Real-time PCR showing all genes exhibited male-biased expression in adult antennae. Functional analyses of the six pheromone receptor genes were then conducted in the heterologous expression system of Xenopus oocytes. HarmOR13 was found to be a specific receptor for the major sex pheromone component Z11-16:Ald. HarmOR6 was equally tuned to both of Z9-16: Ald and Z9-14: Ald. HarmOR16 was sensitively tuned to Z11-16: OH. HarmOR11, HarmOR14 and HarmOR15 failed to respond to the tested candidate pheromone compounds. Our experiments elucidated the functions of some pheromone receptor genes of H. armigera. These advances may provide remarkable evidence for intraspecific mating choice and speciation extension in moths at molecular level.
Female mice exhibited higher survival rate than males after pneumonia, with a reversal of this pattern following ozone exposure. Surfactant protein A (SP-A) plays an important role in innate immunity and SP-A (−/−) mice were more susceptible to pneumonia than wild type mice. Here, we investigated underlying mechanisms of the differential susceptibility of mice to pneumonia. Wild type and SP-A (−/−) C57BL/6J male and female mice were exposed to ozone or filtered air (FA) and then infected intratracheally with Klebsiella pneumoniae. Blood, spleen, and lung were analyzed for bacterial counts, lung and spleen weights, and sex hormone and cortisol levels were measured in plasma within two days post-infection. We found: 1) in the absence of ozone-induced oxidative stress, males had higher level of bacterial dissemination compared to females; ozone exposure decreased pulmonary clearance in both sexes and ozone-exposed females were more affected than males; 2) ozone exposure increased lung weight, but decreased spleen weight in both sexes, and in both cases ozone-exposed females were affected the most; 3) plasma cortisol levels in infected mice changed: ozone-exposed > FA-exposed, females > males, and infected > non-infected; 4) no major sex hormone differences were observed in the studied conditions; 5) differences between wild type and SP-A (−/−) mice were observed in some of the studied conditions. We concluded that reduced pulmonary clearance, compromised spleen response to infection, and increased cortisol levels in ozone-exposed females, and the higher level of lung bacterial dissemination in FA-exposed males, contribute to the previously observed survival outcomes.
Pneumonia infection; Lung inflammation; Spleen; Hormones; CFU; Cortisol
The genetic contribution to the development of bronchopulmonary dysplasia (BPD) in prematurely born infants is substantial, but information related to the specific genes involved is lacking. We conducted a case-control single nucleotide polymorphism (SNP) association study of candidate genes (n=601) or 6,324 SNPs in 1,091 prematurely born infants with gestational age <35 weeks, with or without neonatal lung disease including BPD. BPD was defined as need for oxygen at 28 days. Genotype analysis revealed, after multiple comparisons correction, two significant SNPs, rs3771150 (IL-18RAP) and rs3771171 (IL-18R1), in African Americans (AA) with BPD (vs. AA without BPD; q<0.05). No associations with Caucasian (CA) BPD, AA or CA RDS, or prematurity in either AA or CA, were identified with these SNPs. Respective frequencies were 0.098 and 0.093 without BPD and 0.38 for each SNP in infants with BPD. In the replication set (82 cases; 102 controls), the p-values were 0.012 for rs3771150 and 0.07 for rs3771171. Combining p-values using Fisher's method, overall p-values were 8.31E-07 for rs3771150, and 6.33E-06 for rs3771171. We conclude, IL-18RAP and IL-18R1 SNPs identify AA infants at risk for BPD. These genes may contribute to AA BPD pathogenesis via inflammatory-mediated processes and require further study.
Surfactant protein A (SP-A), encoded by two functional genes, SP-A1 and SP-A2, is essential for the inflammatory process and host defence in the lungs. Recent studies have demonstrated the extrapulmonary expression of SP-A. Similar to the lungs, the kidneys are organs exposed to external pathogens. The present study evaluated the expression and location of SP-A in the kidneys. The effect of lipopolysaccharide (LPS) on the expression of SP-A subtypes was also studied in renal tubular epithelial (HK-2) cells.
Immunohistochemical staining was performed using polyclonal antibody against SP-A. RT-PCR was also performed using mRNA from normal human renal tissues and HK-2 cells. The expressions of the SP-A1 and SP-A2 genes were determined by PCR-based RFLP analysis, gene-specific amplification, and direct sequencing of RT-PCR products. Western blot was conducted to analyse the SP-A protein. HK-2 cells were treated with LPS at various concentrations (0, 0.1, 1, 2, 5, and 10 μg/mL) for 8 h and at 5 μg/mL at various time points (0, 2, 4, 8, 16, and 24 h). The LPS-induced expressions of SP-A1 and SP-A2 mRNA and protein were analysed by RT-PCR and Western blot.
SP-A was localised in the renal tubular epithelial cells in the proximal and distal convoluted tubules. SP-A1 and SP-A2 mRNA and protein were expressed in HK-2 cells and human renal tissues, which were significantly increased in time- and dose-dependent manners after LPS treatment (P < 0.05).
Human renal tubular epithelial cells can express both SP-A1 and SP-A2 genes, which may play important roles in the inflammatory modulation of the kidney.
Surfactant protein A1; Surfactant protein A2; Human renal tubular epithelial cells; Lipopolysaccharide; Inflammatory modulation
Antennal olfaction is extremely important for insect survival, mediating key behaviors such as host preference, mate choice, and oviposition site selection. Multiple antennal proteins are involved in olfactory signal transduction pathways. Of these, odorant receptors (ORs) and ionotropic receptors (IRs) confer specificity on olfactory sensory neuron responses. In this study, we identified the olfactory gene repertoire of the economically important agricultural pest moth, Helicoverpa armigera, by assembling the adult male and female antennal transcriptomes. Within the male and female antennal transcriptomes we identified a total of 47 OR candidate genes containing 6 pheromone receptor candidates. Additionally, 12 IR genes as well as 26 odorant-binding proteins and 12 chemosensory proteins were annotated. Our results allow a systematic functional analysis across much of conventional ORs repertoire and newly reported IRs mediating the key olfaction-mediated behaviors of H. armigera.
Aedes aegypti and Anopheles gambiae are among the best-characterized mosquito species within the Culicinae and Anophelinae mosquito clades which diverged ∼150 million years ago. Despite this evolutionary distance, the olfactory systems of these mosquitoes exhibit similar morphological and physiological adaptations. Paradoxically, mosquito odorant receptors, which lie at the heart of chemosensory signal transduction pathways, belong to a large and highly divergent gene family. We have used 2 heterologous expression systems to investigate the functional characteristics of a highly conserved subset of Ors between Ae. aegypti and An. gambiae to investigate whether protein homology correlates with odorant-induced activation. We find that these receptors share similar odorant response profiles and that indole, a common and ecologically relevant olfactory cue, elicits strong responses from these homologous receptors. The identification of other highly conserved members of this Or clade from mosquito species of varying phylogenetic relatedness supports a model in which high sensitivity to indole represents an ancient ecological adaptation that has been preserved as a result of its life cycle importance. These results provide an understanding of how similarities and disparities among homologous OR proteins relate to olfactory function, which can lead to greater insights into the design of successful strategies for the control of mosquito-borne diseases.
Aedes aegypti; Anopheles gambiae; indole; mosquito; odorant-receptor; olfaction; oviposition
It has been shown that female mice with pneumonia have a survival advantage over males, but this is reversed if ozone exposure precedes infection. The purpose of this study was to investigate factors that underlie these observations, by studying histopathologic changes in lung and extrapulmonary (spleen and liver) tissues after ozone or filtered air (FA) exposure followed by pulmonary bacterial infection. Male and female wild type C57BL/6J mice were exposed to ozone or FA, then anesthetized and infected intratracheally with Klebsiella pneumoniae bacteria. Tissues (lung, spleen, and liver) were subjected to histopathologic analysis at 48 h post-infection. We found that after infection, 1) the severity of inflammation was higher, the affected area of the lung was larger, and spleen red pulp myelopoiesis was lower in ozone-exposed mice compared to FA-exposed animals in both sexes; 2) more pronounced extrapulmonary lesions (in liver and spleen) were observed in FA-exposed males compared to FA-exposed females; and 3) excessive lung inflammatory response was detected in ozone-exposed females compared to ozone-exposed males. We concluded that different risk factors contribute to the differential outcome of pneumonia between sexes in the presence or absence of ozone-induced oxidative stress. In specific, the excessive lung inflammation and higher risk for extrapulmonary lesions in ozone-exposed infected females and in FA-exposed infected males appear to play, respectively, a dominant role in the previously observed respective survival outcomes.
Sex; infection; lung inflammation; spleen function; pathology
Many species of mosquitoes, including the major malaria vector Anopheles gambiae, utilize carbon dioxide (CO2) and 1-octen-3-ol as olfactory cues in host-seeking behaviors that underlie their vectorial capacity. However, the molecular and cellular basis of such olfactory responses remains largely unknown.
Here, we use molecular and physiological approaches coupled with systematic functional analyses to define the complete olfactory sensory map of the An. gambiae maxillary palp, an olfactory appendage that mediates the detection of these compounds. In doing so, we identify three olfactory receptor neurons (ORNs) that are organized in stereotyped triads within the maxillary-palp capitate-peg-sensillum population. One ORN is CO2-responsive and characterized by the coexpression of three receptors that confer CO2 responses, whereas the other ORNs express characteristic odorant receptors (AgORs) that are responsible for their in vivo olfactory responses.
Our results describe a complete and highly concordant map of both the molecular and cellular olfactory components on the maxillary palp of the adult female An. gambiae mosquito. These results also facilitate the understanding of how An. gambiae mosquitoes sense olfactory cues that might be exploited to compromise their ability to transmit malaria.
Heat sensitivity is a sensory modality that plays a critical role in close-range host-seeking behaviors of adult female Anopheles gambiae, the principal Afrotropical vector for human malaria. An essential step in this activity is the ability to discriminate and respond to increases in environmental temperature gradients through the process of peripheral thermoreception. Here, we report on the characterization of the anopheline homolog of the transient receptor potential (TRP) A1/ANKTM1 channel that is consistent with its role as a heat-sensor in host-seeking adult female mosquitoes. We identify a set of distal antennal sensory structures that specifically respond to temperature gradients and express AgTRPA1. Functional characterization of AgTRPA1 in Xenopus oocytes supports its role in the molecular transduction of temperature gradients in An. gambiae, providing a basis for targeting mosquito heat responses as a means toward reducing malaria transmission.
coeloconic sensilla; temperature receptor; TRP channel
Innate immunity mechanisms play a critical role in the primary response to invading pathogenic microorganisms and other insulting agents. The innate lung immune system includes lung surfactant, a lipoprotein complex that carries out a function essential for life, that is, reduction of the surface tension at the air–liquid interphase of the alveolar space. By means of this function, pulmonary surfactant prevents lung collapse, therefore ensuring normal lung function and lung health. Pulmonary surfactant contains a number of host-defense molecules that are involved in the elimination of pathogens, viruses, particles, allergens, and other insults, as well as in the control of inflammation. This review is concerned with one of the surfactant proteins, the human (h) surfactant protein A (hSP-A), which, in addition to its role in surfactant-related functions, plays an important role in the modulation of lung host defense. The hSP-A locus has been identified with extensive complexity that may have an impact on its function, structure, and regulation. In humans, two genes—SP-A1 (SFTPA1) and SP-A2 (SFTPA2)—encode SP-A, with SP-A2 gene products being more biologically active than SP-A1 in most of the in vitro assays investigated. Although the two hSP-A genes share a high level of sequence similarity, differences in the structure and function between SP-A1 and SP-A2 have been observed in recent studies. In this review, we discuss the human SP-A complexity and how this may affect SP-A function.
innate immunity; phagocytosis; genetic variants; post-translational modifications; structure–function correlations