Urotensin II in Invertebrates: From Structure to Function in Aplysia californica

Neuropeptides are ancient signaling molecules that are involved in many aspects of organism homeostasis and function. Urotensin II (UII), a peptide with a range of hormonal functions, previously has been reported exclusively in vertebrates. Here, we provide the first direct evidence that UII-like peptides are also present in an invertebrate, specifically, the marine mollusk Aplysia californica. The presence of UII in the central nervous system (CNS) of Aplysia implies a more ancient gene lineage than vertebrates. Using representational difference analysis, we identified an mRNA of a protein precursor that encodes a predicted neuropeptide, we named Aplysia urotensin II (apUII), with a sequence and structural similarity to vertebrate UII. With in-situ hybridization and immunohistochemistry, we mapped the expression of apUII mRNA and its prohormone in the CNS and localized apUII-like immunoreactivity to buccal sensory neurons and cerebral A-cluster neurons. Mass spectrometry performed on individual isolated neurons, and tandem mass spectrometry on fractionated peptide extracts, allowed us to define the posttranslational processing of the apUII neuropeptide precursor and confirm the highly conserved cyclic nature of the mature neuropeptide apUII. Electrophysiological analysis of the central effects of a synthetic apUII suggests it plays a role in satiety and/or aversive signaling in feeding behaviors. Finding the homologue of vertebrate UII in the numerically small CNS of an invertebrate animal model is important for gaining insights into the molecular mechanisms and pathways mediating the bioactivity of UII in the higher metazoan.     

Various indicators of humoral immunity in patients with hematopoietic hypoplasia after bone marrow transplantation]

The authors examined 65 patients with hypoplasia of the hemopoiesis following bone marrow transplantation. To patients of the 1st group the bone marrow was chosen by erythrocytic antigens only, and to patients of the 2nd group both by erythrocytic and by leukocytic antigens. The data obtained pointed to the reduction of isoimmunization to the antigens of leukocytes and platelets in the patients with hypoplasia of the hemopoiesis following transplantation of the histocompatible bone marrow, in comparison with the patients in whom the bone marrow was chosen only by erythrocytic antigens alone.     

A new rabies vaccine in public health practice in the USSR

A new antirabies vaccine prepared on the basis of virus grown in the ovine brain, purified from 85-90% of brain-tissue ballast substances and inactivated with beta-propilactone has been developed at the Moscow Research Institute of Viral preparations (USSR Acad. Med. Sci.). The preparation produces no neuro-allergenic effect in tests on guinea pigs. When injected to humans, the vaccine shows much lower reactogenicity than Fermi vaccine. High antigenic and immunogenic activity of the new vaccine has made it possible to work out a less intensive immunization schedule in comparison with that used for immunization with Fermi vaccine and nonconcentrated tissue-culture vaccine, viz. doses of 3 ml for 12 days or doses of 3 ml for 20 days with two booster immunizations. The preparation has been introduced into medical practice.     

Mapping of the genetic determinant controlling Salmonella K-antigen synthesis. II. Nonmotile mutants of Salmonella typhimurium

According to the preliminary data, S. typhimurium K-antigen is located in the area of minutes 40-44 on the Salmonella chromosome map. The formation of nonmotile mutants from motile Salmonella strains was induced by the action of nitrosoguanidine. Two main groups of mutants differing in their reaction of agglutination with H- and K-antisera were obtained: Mot-H-K- (motA or motB mutants) and Mot-H-K- (H1- or fla- mutants). The transduction transfer of the sign of motility by phage P22HT to H-K- mutants and to H1- and flaE- mutants led to the restoration of agglutination ability with respect to H- and K-antisera in all Mot+ transductants under study simultaneously. The restoration of H+K+ phenotype was also observed in spontaneous motile revertants obtained from H-K- mutants. Thus, the gene controlling the synthesis of K-antigen in Salmonellae was shown to be incorporated into the Fla operon, the regulatory system of the operon controlling the expression of this gene.     

Study of Male Mating Behavior in SomeDrosophila melanogaster Strains in Experiments with Fertilized Females

Male courtship ritual is among the main behavioral characteristics of Drosophila. This is a complex, genetically determined process consisting of four general stages: orientation, vibration, licking, and attempts at copulation (or successful copulation). Several genes are known that control some stages of this behavior. Most of them have pleiotropic effects and are involved in other biological processes. Earlier, we have shown that a mutation in locus flamenco (20A1-3), which controls transposition and infectivity of retrotransposongypsy (MDG4), is involved in the genetic control of behavior. In strains mutant for this locus, the male mating activity is decreased and the structure of courtship ritual is changed. To understand the mechanisms of these changes, it is important to study all behavioral stages in genetically identical strains. For this purpose, the normal allele of geneflamenco from the X chromosome of the wild-type strain Canton S was introduced into strain SS carrying flam ^MS. This offers new opportunities in studying the role of gene flamenco in the control of mating behavior in Drosophila.