The eggs of Utetheisa ornatrix contain pyrrolizidine alkaloids. These compounds are contributed by both parents, who sequester them as larvae from their food plants.Females receive alkaloid from the males at mating, apparently by seminal infusion, and transmit this alkaloid together with alkaloid of their own to the eggs. Field and laboratory tests showed that the alkaloids protect eggs from predators. The alkaloidal contribution of the male, although smaller than that of the female, itself provides significant egg protection. A previously identified pheromone, derived by the male from the alkaloid and emitted during precopulatory behavior, may announce the male alkaloidal worth to the female.
Semiochemical interactions between the spruce bark beetle Ips typographus, its predators Medetera setiventris, Thanasimus formicarius and Thanasimus femoralis, and the host Norway spruce, Picea abies, were studied in the field. The chemicals S-cis-verbenol, 2-methyl-3-buten-2-ol, ipsdienol, (+)-a-pinene, ())-a-pinene, (±)-a-pinene, limonene, camphor and their naturally occuring mixtures were used as trap baits in a multiple-choice design that allowed for comparison of their attractivity for the focal species. Medetera was attracted to both the prey aggregation pheromone and its multifunctional component, ipsdienol. On the contrary, both Thanasimus species responded predominantly to ipsdienol and less to the prey aggregation pheromone. In the case of I. typographus, the attractivity of aggregation pheromone seems to be increased by the addition of a mixture of monoterpenic tree volatiles, and by addition of ipsdienol. Bark beetles and predators showed species-specific responses to volatile mixtures representing different stages of tree decay and different stages of bark beetle colony establishment. These responses correlates with the optimal foraging habitat of each species. None of the predator species responded to 2-methyl-3-buten-2-ol, a substantial component of I. typographus pheromonal bouquet, thus it is hypothesized that only substances of monoterpenic origin attract predators.
We performed a 2-DE analysis of proteins of the newly established spontaneously immortalized clonal cell line EM-G3 derived from a primary lesion of infiltrating ductal breast carcinoma. EM-G3 cells may represent progenitors of the mammary epithelial cells spontaneously immortalized in early phase of cancerogenesis. We compared the protein profile of EM-G3 line with proteins from populations of normal mammary epithelial cells (NME), and determined the phenotype of both types of cells. NME cells are a mixture of both main cell types in breast epithelia, myoepithelial and luminal cells. The EM-G3 breast cancer cell line has a unique basal-like phenotype. We identified proteins that are differently expressed in these cells. Cytokeratin 16, cytokeratin 19, squamous cell carcinoma antigen 1, caphepsin B and caspase 14 were predominantly expressed by NME cells. Cytokeratin 13, isoelectric variant of annexin 5, isoelectric variant of chloride intracellular channel protein 1, glyoxalase 1 and glutamine synthetase were predominantly expressed by EM-G3 cells. The proteins up-regulated in EM-G3 cells may represent potential protein markers of mammary epithelial cells progenitors and may be important in early phase of carcinogenesis.
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