Defense of Scots pine against sawfly eggs (Diprion pini) is primed by exposure to sawfly sex pheromones.

Plants respond to insect infestation with defenses targeting insect eggs on their leaves and the feeding insects. Upon perceiving cues indicating imminent herbivory, such as damage-induced leaf odors emitted by neighboring plants, they are able to prime their defenses against feeding insects. Yet it remains unknown whether plants can amplify their defenses against insect eggs by responding to cues indicating imminent egg deposition. Here, we tested the hypothesis that a plant strengthens its defenses against insect eggs by responding to insect sex pheromones. Our study shows that preexposure of Pinus sylvestris to pine sawfly sex pheromones reduces the survival rate of subsequently laid sawfly eggs. Exposure to pheromones does not significantly affect the pine needle water content, but results in increased needle hydrogen peroxide concentrations and increased expression of defense-related pine genes such as SOD (superoxide dismutase), LOX (lipoxygenase), PAL (phenylalanine ammonia lyase), and PR-1 (pathogenesis related protein 1) after egg deposition. These results support our hypothesis that plant responses to sex pheromones emitted by an herbivorous insect can boost plant defensive responses to insect egg deposition, thus highlighting the ability of a plant to mobilize its defenses very early against an initial phase of insect attack, the egg deposition.

[Effect of natural and postradiation volatile secretions of mice on the immune reactivity and blood cellularity of irradiated animals].

It has been shown that natural and postradiation volatile urinary secretions of mice can remotely restore the immune reactivity and blood indices reduced as a result of exposure of laboratory mice to ionizing radiation. Antibody formation in spleen of gamma-irradiated (1 Gy) CBA strain mice was increased after exposure of both syngeneic and allogeneic animals with urine volatile secretions. Volatile natural secretions of intact mice have a more pronounced antibody stimulating activity than volatile secretions from animals exposed to gamma-radiation. Immunoreactivity ofy-irradiated C57B16 strain mice with low olfactory reactivity increases only after their exposure with volatile secretions of intact syngeneic animals. The total number of leukocytes and lymphocytes in the peripheral blood of gamma-irradiated (1 Gy) inbred mice increases after exposure with secretions obtained from them before irradiation. The role of hemo-signalling in the selective stimulation of immunity and blood content in conditions of radiation damage is discussed.

[Effect of volatile excretions induced with thymus-dependent antigen in female mice on the behavioural responses of males].

It was found that thymus-dependent antigen sheep red blood cells in the optimal immunogenic dose (1 x 10(8) cells/mouse) induced in female mice of CBA and B6 strain secretion of attractive urinary volatile components (VCs), and in the supraoptimal dose (1 x 10(9) cells/mouse)--aversive VCs for intact males CBA strain. In a direct comparison of the properties ofVCs-immunized mice of CBA and B6, a modification of the effect of constitutive chemosignalling: disturbance of ability of females VCs to attract allogeneic males, was observed. The role of thymus-dependent antigen dose and sex of animals in the mechanism of generation of antigen-induced chemosignals is discussed.

[The sexual behavior, chemosignals and reproductive success in the male mice during activation of nonspecific immune response].

Hypothesis of reproductive compensation (Gowaty et al., 2007) suggests that constraining of free mating preference leads to reduction of the viability of progenies, which could be, partially, compensated by higher fecundity of the constrained parents. We consider infection as one of natural causes constraining female mating choice, because infection or immune response to infection can modulate male sexual demonstrations. Here we studied influence of LPS (bacterial endotoxin, activating non-specific immune response) on chemical attractiveness, sexual behavior and reproductive success in the outbreed male mice mated with the non-treated females. Single or repeated LPS administrations lead to increase of scent attractiveness of the male urine and soiled bedding for the non-estrus females. Injection of LPS (dose 50 mkg/kg) did not suppress the male sexual behavior. Time from pairing to successful mating correlates positively with the body mass of 16 day embryo. Embryos development, assessed by their body mass, was reduced in the females mated with the LPS-treated males. Higher level of plasma progesterone found in the females mated with the LPS-treated males, and shift of successful mating to the later time did not compensate reduction of embryo mass. At the same time the females mated with the LPS-treated males showed lower embryo lost in comparison with the females mated with the control males.

Development and application of an ELISA for a sex pheromone released by the male sea lamprey (Petromyzon marinus L.).

An enzyme-linked immunosorbent assay (ELISA) has been developed for a conjugated bile acid, 7alpha,12alpha,24-trihydroxy-5alpha-cholan-3-one 24-sulfate (commonly referred to as 3-keto petromyzonol sulfate [3kPZS]), a pheromone released by reproductively mature male sea lampreys to attract sexually mature females. A polyclonal antiserum against the pheromone was raised by injecting 3-keto petromyzonol 24-hemisuccinate (3kPZ-HS) conjugated to bovine serum albumin into rabbits. The enzyme label was prepared by conjugating 3kPZ-HS to acetylcholinesterase. The standard curve had a working range of 20 pg-10 ng/well. Intra- and inter-assay variations were less than 5 and 12%, respectively. The antiserum had 100% cross-reaction with 3-keto petromyzonol and 3-keto allocholic acid but less than 0.2% cross-reaction with petromyzonol, allocholic acid, cholic acid, and taurolithocholic acid sulfate. The assay was applied to water which had been conditioned for 4h by either larvae, parasitic juveniles, ovulating females, pre-spermiating males, or spermiating males. Immunoactive material (average 200 ng/ml, which is equivalent to 500 microg animal/h) was only found in water from the reproductively mature males and diluted parallel with the standard curve. Assay of water samples collected from male lampreys in bisected aquaria also established that 99.6% of the immunoactive material emanated from the front end of the fish. This assay has applications in both physiological and ecological aspects of sea lamprey reproduction.

Neuroanatomy and immunocytochemistry of the median neuroendocrine cells of the subesophageal ganglion of the tobacco hawkmoth, Manduca sexta: immunoreactivities to PBAN and other neuropeptides.

The median neuroendocrine cells of the subesophageal ganglion, important components of the neuroendocrine system of the tobacco hawkmoth, Manduca sexta, have not been well investigated. Therefore, we studied the anatomy of these cells by axonal backfills and characterized their peptide immunoreactivities. Both larvae and adults were examined, and developmental changes in these neuroendocrine cells were followed. Processes of the median neuroendocrine cells project to terminations in the corpora cardiaca via the third and the ventral nerves of this neurohemal organ, but the ventral nerve of the corpus cardiacum is the principal neurohemal surface for this system. Cobalt backfills of the third cardiacal nerves revealed lateral cells in the maxillary neuromere and a ventro-median pair in the labial neuromere. Backfills of the ventral cardiacal nerves revealed two ventro-median pairs of cells in the mandibular neuromere and two ventro-median triplets in the maxillary neuromere. The efferent projections of these cells are contralateral. The anatomy of the system is basically the same in larvae and adults. The three sets of median neuroendocrine cells are PBAN- and FMRFamide-immunoreactive, but only the mandibular and maxillary cells are proctolin-immunoreactive. During metamorphosis, the mandibular and maxillary cells also acquire CCK-like immunoreactivity and the labial cells become SCP- and sulfakinin-immunoreactive. Characteristics of FMRFamide-like immunostaining suggest that the median neuroendocrine cells may contain one or more of the FLRFamides that have been identified in M. sexta. The mandibular and maxillary neuroendocrine cells appear to produce the same set of hormones, and a somewhat different set of hormones is produced by the labial neuroendocrine cells. Two pairs of interneurons immunologically related to the neurosecretory cells are associated with the median maxillary neuroendocrine cells. These cells are PBAN-, FMRFamide-, SCP-, and sulfakinin-immunoreactive and project to arborizations in the brain and all ventral ganglia. These interneurons appear to have extensive modulatory functions in the CNS.

Biochemical, immunological and ultrastructural characterization of aggregation substances encoded by Enterococcus faecalis sex-pheromone plasmids.

The sex-pheromone system of Enterococcus faecalis can be viewed as a unique and highly efficient plasmid-collection mechanism. The contact needed for transfer of the conjugative sex-pheromone plasmids is mediated by an adhesin, called aggregation substance, which is encoded by these plasmids. We show here that for 17 of the 18 sex-pheromone plasmids (pAM373 being the exception) described to date, their adhesins are immunologically related to each other. In each case, we observed the presence of an N-terminal fragment of about 78 kDa in addition to the 137-kDa form of mature aggregation substance. The cross-reactions were different for the various plasmids. In the case of pPD1 the 78-kDa fragment reacted only weakly. The aggregation substance encoded by sex-pheromone plasmid pAD1 (Asa1) was characterized in detail. The conditions used for SDS/PAGE had a drastic influence on the migration behavior of mature aggregation substance and differently migrating, interconvertible forms were identified. Preliminary data indicate that Asa1 might be a glycoprotein. Antibodies were isolated which are directed against the N- and C-terminal parts of aggregation substance. They showed about the same reactivity on Western blots; however, only antibodies directed against the N-terminal part of the aggregation substance could inhibit the bacterial cell/cell contact. The reactions of the two antibody preparations with induced cells of E. faecalis was analyzed by transmission electron microscopy. The results indicated that especially the N-terminal part of aggregation substance is exposed on the cell surface of E. faecalis; the C-terminal part seems to be much less exposed.

Specific and common epitopes in mating pheromones of Euplotes raikovi revealed by monoclonal antibodies.

Polypeptide mating pheromones Er-1 and Er-2, purified from the supernatant of Euplotes raikovi cultures of mating type I and mating type II, respectively, were used to immunize mice and obtain monoclonal antibodies. Five hybridoma clones producing antibodies specific to the mating pheromones were selected. They were analyzed for immunospecificity by immunoperoxidase assay, immunoblotting, and for their efficacy in inhibition of mating pheromone activity. Monoclonal antibodies from two hybridoma clones recognized only the mating pheromone used as antigen: those from the other three clones reacted, to comparable extents, with both mating pheromones. On the basis of these results it was assumed that two immunogenic sites exist in Er-1 and Er-2, one specific and the other common to both mating pheromones.

Monoclonal antibodies to cell surface antigens involved in sex pheromone induced mating in Streptococcus faecalis.

Hybridoma cell lines producing monoclonal antibodies to Streptococcus faecalis cell surface antigens were constructed. Some of the antibodies isolated were directed against surface components involved in pheromone-induced mating. This paper describes the use of the monoclonal antibodies to identify antigenically related surface components detected by immunoprecipitation and Western blotting, their use in pheromone response assays, and their use as functional inhibitors in mating experiments.