Effects of ablation of the pars intercerebralis on ecdysteroid quantities and yolk protein expression in the blowfly Protophormia terraenovae

Quantities of ecdysteroid are compared in the haemolymph and ovaries of the blowfly Protophormia terraenovae Robineau‐Desvoidy (Diptera: Calliphoridae) under reproductive (LD 18 : 6 h at 25 °C) and diapause (LD 12 : 12 h at 20 °C) conditions. The effects of ablation of the pars intercerebralis or ovaries on ecdysteroid quantities and of ablation of the pars intercerebralis on yolk protein expression are examined. Under reproductive conditions, the levels of ecdysteroid in vitellogenic females are high, although the levels in previtellogenic females and females with mature ovaries are low. Under diapause conditions, there are low quantities of ecdysteroid in both the haemolymph and ovaries. Ecdysteroid titres in the haemolymph are not significantly affected by the removal of the ovaries, suggesting that tissues other than the ovaries are also involved in the production of ecdysteroids. Reproductive females in which the pars intercerebralis of the brain is experimentally ablated have ecdysteroid levels that are not significantly different from sham‐operated or intact females. However, yolk protein expression in the fat body is suppressed after removal of the pars intercerebralis. These results suggest that the suppression of ecdysteroid levels in the haemolymph and ovaries is associated with reproductive diapause, and that the pars intercerebralis could play a role in yolk protein synthesis without mediating ecdysteroid production.     

Development of AC microelectrophoresis for rapid protein affinity evaluation

We have developed a new method for evaluating the affinity interactions between two different proteins by applying an alternating current (AC) voltage to a micro-flow channel. An AC voltage was applied to the protein-modified microspheres in the micro-flow channel, which resulted in the oscillation of the microspheres owing to their surface charges. The oscillation amplitude showed a linear relationship with the charge density of the microspheres. As an example for protein affinity measurement, the amplitude changes of a profilin-modified microsphere were measured by the addition of actin. In the same electrical condition, the oscillation amplitude of the profilin-modified microsphere increased by ≈175% by binding with actin. Similar results in the principle were obtained for the affinity interaction between biotin and streptavidin. The results showed that the higher the charge density of the microspheres induced by binding with different proteins, the higher the oscillation amplitude of the microspheres, thus, suggesting a possible application of the micro-flow channel and AC voltage on the protein property study, as well as on the biosensor application using the oscillation amplitude changes.     

Effects of wing-pad removal and corpus allatum implantation on development of wings, flight muscles, and related structures in the striped ground cricket, Allonemobius fasciatus

ABSTRACT. Removal of a hindwing pad from late instar nymphs of the striped ground cricket, Allonemobius fasciatus DeGeer (Gryllidae) inhibits the formation of long-winged adults. All nymphs become short-winged when their hindwing pad is removed during the sixth (penultimate) instar or during the first 2 days of the seventh instar. When a hindwing pad is removed on day 4 of the seventh instar or later, there is no effect on wing development and at least 50% of the crickets emerge as long-winged adults as in controls.
The period sensitive for removal of a hindwing pad varies among different structures, e.g. elytra, hindwings, flight muscles, and the acrotergite of the first abdominal segment. As a result, some intermediate forms are produced when a hindwing pad is removed in the middle of the seventh instar.
Implantation of corpora allata (CA) into late instar nymphs also inhibits formation of long-winged adults. When CA are implanted on day 2 or 3 of the seventh instar, some of the resulting adults have abnormally short elytra. Implantation of CA at an earlier stage produces supernumerary (eighth instar) nymphs.     

Grouping Antigens of Four Lactobacillus Species and Their Characteristics

Antigenic analyses of Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus brevis and Lactobacillus buchneri were carried out by double immunodiffusion in agar. Antigens were extracted from whole cells and cell wall preparations with cold trichloroacetic acid. Most strains of the four species possessed antigen 9 in their cell walls. Another antigen, antigen 10, was found in the cell walls of all the strains of L. brevis and L. buchneri, and in some strains of L. lactis, but not in L. bulgaricus. Fractionation of the antigens was attempted using the cell wall extracts of L. lactis L-10 with only antigen 9 and of L. brevis X-1 with both antigens 9 and 10. The partially purified fractions of antigen 9 and of the complex of antigens 9 and 10 were obtained by zone electrophoresis. However, antigen 10 from the complex could not be separated by the same method or gel filtration on Sephadex G-100 since the two antigens 9 and 10 of the complex always behaved together. The fraction of antigen 9 consisted almost entirely of glycerol and glucose as sugar components, the molar ratio being 2:1. The complex of antigens 9 and 10 also consisted of the same sugars, and the molar ratio of glycerol: glucose was 4:1. Inhibition tests indicated that the immunodominant component of antigen 9 was α-methylglucoside (glucose), and most probably the determinant is a glucosylated glycerol teichoic acid. It was considered that the determinant of antigen 10 is a glycerol teichoic acid although glucosamine and galactosamine inhibited effectively the reaction between antigen 10 and its antibody.     

Generation of Rhesus Macaque-Tropic HIV-1 Clones That Are Resistant to Major Anti-HIV-1 Restriction Factors

Human immunodeficiency virus type 1 (HIV-1) replication in macaque cells is restricted mainly by antiviral cellular APOBEC3, TRIM5α/TRIM5CypA, and tetherin proteins. For basic and clinical HIV-1/AIDS studies, efforts to construct macaque-tropic HIV-1 (HIV-1mt) have been made by us and others. Although rhesus macaques are commonly and successfully used as infection models, no HIV-1 derivatives suitable for in vivo rhesus research are available to date. In this study, to obtain novel HIV-1mt clones that are resistant to major restriction factors, we altered Gag and Vpu of our best HIV-1mt clone described previously. First, by sequence- and structure-guided mutagenesis, three amino acid residues in Gag-capsid (CA) (M94L/R98S/G114Q) were found to be responsible for viral growth enhancement in a macaque cell line. Results of in vitro TRIM5α susceptibility testing of HIV-1mt carrying these substitutions correlated well with the increased viral replication potential in macaque peripheral blood mononuclear cells (PBMCs) with different TRIM5 alleles, suggesting that the three amino acids in HIV-1mt CA are involved in the interaction with TRIM5α. Second, we replaced the transmembrane domain of Vpu of this clone with the corresponding region of simian immunodeficiency virus SIVgsn166 Vpu. The resultant clone, MN4/LSDQgtu, was able to antagonize macaque but not human tetherin, and its Vpu effectively functioned during viral replication in a macaque cell line. Notably, MN4/LSDQgtu grew comparably to SIVmac239 and much better than any of our other HIV-1mt clones in rhesus macaque PBMCs. In sum, MN4/LSDQgtu is the first HIV-1 derivative that exhibits resistance to the major restriction factors in rhesus macaque cells.     

l-Acylimidazoles with Broad-spectrum Fungicidal Activity

The membrane lipids of six higher plants that differ in salt tolerance were analyzed and compared. The root lipids increased in a ratio of glycolipid/phospholipid with increasing salt- tolerance. A similar increase in the ratio was observed with increasing external salinity when halophytic orach and salt-sensitive cucumber were exposed to varying salinity, although the latter plant was limited to only a little increase. Measurements of ion-transport rates with artificial lipid membranes revealed that the root lipids from a salt-resistant plant formed a more permeable membrane than those from a salt-sensitive species. It was found that the membrane permeability was related to the glycolipid/phospholipid ratio in the membrane lipids, where the glycolipids were stimulative and the phospholipids were repressive for ion-flow. These different effects of the two lipid classes may be attributed to their molecular species and head groups.     

A series of nonsecosteroidal vitamin D receptor agonists for osteoporosis therapy

In an extension of our study on gamma hydroxy carboxylic acid analogs, we explored a series of nonsecosteroidal vitamin D receptor (VDR) agonists in which 1,3-diol of 1,25(OH)₂D₃ had been replaced by aryl acetic acid. These analogs showed very potent activity in vitro compared with 1,25(OH)₂D₃. An X-ray analysis of 8d showed that the inserted phenyl ring well mimicked the folded methylene linker of the gamma hydroxy carboxylic acid moiety but the carboxylic acid of 8d interacted with VDR in a different manner from gamma hydroxy carboxylic acids. Through our in vivo screening in an osteoporosis rat model using immature rats, we identified a potent active vitamin D₃ analog, compound 7e. In mature rats of the same model, compound 7e also showed good PK profiling and excellent ability to prevent bone mineral density loss without severe hypercalcemia. Our nonsecosteroidal VDR agonist 7e (CH5036249) could be a possible new drug candidate for treating osteoporosis in human.