Why flies? Inexpensive public engagement exercises to explain the value of basic biomedical research on Drosophila melanogaster

Invertebrate model organisms are powerful systems for uncovering conserved principles of animal biology. Despite widespread use in scientific communities, invertebrate research is often severely undervalued by laypeople. Here, we present a set of simple, inexpensive public outreach exercises aimed at explaining to the public why basic research on one particular invertebrate, the insect Drosophila melanogaster, is valuable. First, we designed seven teaching modules that highlight cutting-edge research in Drosophila genetics, metabolism, physiology, and behavior. We then implemented these exercises in a public outreach event that included both children and adults. Quantitative evaluation of participant feedback suggests that these exercises 1) teach principles of animal biology, 2) help laypeople better understand why researchers study fruit flies, and 3) are effective over a wide range of age groups. Overall, this work provides a blueprint for how to use Drosophila as a vehicle for increasing public awareness and appreciation of basic research on genetically tractable insects in particular and invertebrates in general.     

Identification of a new human coronavirus

Three human coronaviruses are known to exist: human coronavirus 229E (HCoV-229E), HCoV-OC43 and severe acute respiratory syndrome (SARS)-associated coronavirus (SARS-CoV). Here we report the identification of a fourth human coronavirus, HCoV-NL63, using a new method of virus discovery. The virus was isolated from a 7-month-old child suffering from bronchiolitis and conjunctivitis. The complete genome sequence indicates that this virus is not a recombinant, but rather a new group 1 coronavirus. The in vitro host cell range of HCoV-NL63 is notable because it replicates on tertiary monkey kidney cells and the monkey kidney LLC-MK2 cell line. The viral genome contains distinctive features, including a unique N-terminal fragment within the spike protein. Screening of clinical specimens from individuals suffering from respiratory illness identified seven additional HCoV-NL63-infected individuals, indicating that the virus was widely spread within the human population.     

Cross‐calibration of different radar systems for monitoring nocturnal bird migration across Europe and the Near East

Large parts of the continents are continuously scanned by terrestrial weather radars to monitor precipitation and wind conditions. These systems also monitor the mass movements of bird, bat, and insect migration, but it is still unknown how many of these systems perform with regard to detection and quantification of migration intensities of the different groups. In this study that was undertaken within five regions across Europe and the Middle East we examined to what extent bird migration intensities derived from different weather radars are comparable between each other and relate to intensities measured by local small‐scaled radars, some of them specifically developed to monitor birds. Good correspondence was found for the relative day‐to‐day pattern in migration intensities among most radar systems that were compared. Absolute intensities varied between different systems and regions. The findings of this study can be used to infer about absolute bird migration intensities measured by different radar systems and consequently help resolving methodological issues regarding the estimation of migrant numbers in the Western‐Palearctic region. It further depicts a scientific basis for the future monitoring of migratory bird populations across a large spatio‐temporal scale, predicting their movements and studying its consequences on ecological systems and human lives.     

The absence of histone H2B monoubiquitination in the Arabidopsis hub1 (rdo4) mutant reveals a role for chromatin remodeling in seed dormancy

Seed dormancy is defined as the failure of a viable seed to germinate under favorable conditions. Besides playing an adaptive role in nature by optimizing germination to the most suitable time, a tight control of dormancy is important in crop plants. Extensive genetic and physiological studies have identified the involvement of several factors, but the molecular mechanisms underlying this process are still largely unknown. We cloned the HISTONE MONOUBIQUITINATION1 (HUB1) gene, of which the mutant (previously identified as reduced dormancy4) has reduced seed dormancy and several pleiotropic phenotypes. HUB1 encodes a C3HC4 RING finger protein. The Arabidopsis thaliana genome contains one HUB1 homolog, which we named HUB2. The hub2 mutant also has reduced seed dormancy and is not redundant with hub1. Homologs of HUB1 and HUB2 in other species are required for histone H2B monoubiquitination. In agreement with this, the ubiquitinated form of histone H2B could not be detected in the hub1 and hub2 mutants. In yeast and human cells, histone H2B monoubiquitination is associated with actively transcribed genes. The hub1 mutant showed altered expression levels for several dormancy-related genes. We propose a role for chromatin remodeling in seed dormancy by H2B monoubiquitination through HUB1 and HUB2.     

Reduced Incidence of Foot-Related Hospitalisation and Amputation amongst Persons with Diabetes in Queensland,Australia

Objective

To determine trends in the incidence of foot-related hospitalisation and amputation amongst persons with diabetes in Queensland (Australia) between 2005 and 2010 that coincided with changes in state-wide ambulatory diabetic foot-related complication management.

Methods

All data from cases admitted for the principal reason of diabetes foot-related hospitalisation or amputation in Queensland from 2005–2010 were obtained from the Queensland Hospital Admitted Patient Data Collection dataset. Incidence rates for foot-related hospitalisation (admissions, bed days used) and amputation (total, minor, major) cases amongst persons with diabetes were calculated per 1,000 person-years with diabetes (diabetes population) and per 100,000 person-years (general population). Age-sex standardised incidence and age-sex adjusted Poisson regression models were also calculated for the general population.

Results

There were 4,443 amputations, 24,917 hospital admissions and 260,085 bed days used for diabetes foot-related complications in Queensland. Incidence per 1,000 person-years with diabetes decreased from 2005 to 2010: 43.0% for hospital admissions (36.6 to 20.9), 40.1% bed days (391 to 234), 40.0% total amputations (6.47 to 3.88), 45.0% major amputations (2.18 to 1.20), 37.5% minor amputations (4.29 to 2.68) (p < 0.01 respectively). Age-sex standardised incidence per 100,000 person-years in the general population also decreased from 2005 to 2010: 23.3% hospital admissions (105.1 to 80.6), 19.5% bed days (1,122 to 903), 19.3% total amputations (18.57 to 14.99), 26.4% major amputations (6.26 to 4.61), 15.7% minor amputations (12.32 to 10.38) (p < 0.01 respectively). The age-sex adjusted incidence rates per calendar year decreased in the general population (rate ratio (95% CI)); hospital admissions 0.949 (0.942–0.956), bed days 0.964 (0.962–0.966), total amputations 0.962 (0.946–0.979), major amputations 0.945 (0.917–0.974), minor amputations 0.970 (0.950–0.991) (p < 0.05 respectively).

Conclusions

There were significant reductions in the incidence of foot-related hospitalisation and amputation amongst persons with diabetes in the population of Queensland over a recent six-year period.     

Transport and posttranslational processing of the vacuolar enzyme α-mannosidase in jack-bean cotyledons

-Mannosidase (EC 3.2.1.24) is a vacuolar enzyme which occurs abundantly in the cotyledons of the jack-bean (Canavalia ensiformis (L.) DC). The mature enzyme is a tetramer with two polypeptides each of relative molecular mass (M_r) 66000 and M_r 44000. The enzyme has an interesting molecular structure because in its native form, it does not bind to concanavalin A (ConA) in spite of the presence of a high-mannose glycan. -Mannosidase is synthesized in the developing cotyledons of jack-beans at the same time as the abundant proteins canavalin and ConA. The enzyme is synthesized as a precursor which has an M_r of 110000 and is associated with the endoplasmic reticulum (ER). Antibodies against the deglycosylated subunits cross-react with the M_r-110000 precursor. Processing of the precursor to the constituent polypeptides occurs posttranslationally, probably in the protein bodies. Immunocytochemical evidence shows that -mannosidase is present in the ER and the Golgi complex of developing cells, and accumulates in the protein bodies.Labeling with [³H]glucosamine shows that after processing only the M_r-66000 polypeptide has glucosamine-containing glycans. The synthesis of these glycans is inhibited by tunicamycin, indicating that they are asparagine-linked oligosaccharides. Analysis of the glycans shows that there is a large glycan that is retained by ConA and a small glycan that is not retained by ConA. The large glycan is only partially sensitive to -mannosidase because of the presence of a terminal glucose residue. Cross-reaction of the large subunit with an antiserum directed against small, complex glycans of plant glycoproteins indicates that this polypeptide probably has a xylose-containing glycan. Pulse-chase experiments carried out in the presence of tunicamycin show that the presence of glycans is not required for transport of -mannosidase out of the ER-Golgi system.Abbreviations ConA concanavalin A - ER endoplasmic reticulum - H L heavy, light subunit - IgG Immunoglobulin G - M_r relative molecular mass - SDS-PAGE sodium dodecylsulfate-polyacrylamide gel electrophoresis     

Correct glycosylation,Golgi-processing,and targeting to protein bodies of the vacuolar protein phytohemagglutinin in transgenic tobacco

We used a heterologous system (transgenic Nicotiana tabacum L.) to investigate the processing, assembly and targeting of phytohemagglutinin (PHA), the lectin of the common bean, Phaseolus vulgaris L. In the bean, this glycoprotein accumulates in the protein bodies of the storage parenchyma cells in the cotyledons, and each polypeptide has a high-mannose glycan attached to Asn12 and a complex glycan on Asn60. The gene for PHA-L, dlec2, with 1200 basepairs (bp) 5 upstream and 1600 bp 3 downstream from the coding sequence was introduced into tobacco using Agrobacterium-mediated transformation (T. Voelker et al., 1987, EMBO J. 6, 3571–3577). Examination of thin sections of tobacco seeds by immunocytochemistry with antibodies against PHA showed that PHA-L accumulated in the amorphous matrix of the protein bodies in the embryo and endosperm. This localization was confirmed using a non-aqueous method to isolate the protein bodies from mature tobacco seeds. The biochemical analysis of tobacco PHA indicated that the signal peptide had been correctly removed, and that the polypeptides formed 6.4 S oligomers; tobacco PHA had a high-mannose glycan at Asn12 and a complex glycan at Asn60. The presence of the complex glycan shows that transport to the protein bodies was mediated by the Golgi complex. At seed maturity, a substantial portion of the PHA-L remained associated with the endoplasmic reticulum and the Golgi complex, as indicated by fractionation experiments using aqueous media and the presence of two high-mannose glycans on some of the polypeptides. Taken together, these data show that insertion of the nascent PHA into the endoplasmic reticulum, signal peptide processing, glycosylation, assembly into oligomers, glycan modification in the Golgi, and targeting of the protein occur faithfully in this heterologous system, although transport may not be as efficient as in bean cotyledons.Abbreviations Asn asparagine - Endo H endoglycosidase H - HPLC high-performance liquid chromatography - IgG immunoglobulin G - M_r relative molecular mass - PAGE polyacrylamide gel electrophoresis - PHA phytohemagglutinin - SDS sodium dodecylsulfate - TFMS trifluoromethanesulfonic acid