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| Photo by Lisa Fallgren Stevens. Limited North American. 1993 Dogs are Bonnie, Jack, Fudge, Tyke, Taffy, Merganser ((left to right) |
Our current research concerns zoonotic agents and host defenses:
- Francisella tularensis is responsible for the zoonotic disease tularemia (rabbit fever). Because F. tularensis is extremely infective and is responsible for high morbidity and mortality, this bacterium is classified by the CDC as a Category A Select Agent.
- Vector Biology: Francisella multiplies inside the cells of vertebrates, arthropods, and protozoa. We ask which bacterial genes in Francisella tularensis novicida are required for replication in cells of arthropod vectors, which trigger an immune response, and which are host-specific.
- Prevalence in nature: We screen for genotypes of F. tularensis in the environment and in wild hosts.
- The Major Histocompatility Complex has alleles that genetically predipose toward disease in dogs. MHC diversity in Alaska sled dogs shows significant overlap with purebreed dogs and with wolves. The frequencies of MHC alleles caribou differ among populations of caribou.
- Bird flu subtypes vary widely among hosts and geographically across the Circumpolar North.
- Prion genes of Alaska caribou and moose pose no obvious barrier to the spread of Chronic Wasting Disease.
G. M. Happ (1968). Quinone and hydrocarbon production in the defensive gland of Eleodes longicollis and Tribolium castaneum (Coleoptera, Tenebrionidae). J. Insect Physiol. 14: 1821-1839.
Defensive allomones are potent cellular toxicants. Histochemical data indicate that less-toxic diphenol glucosides are hydrolyzed and oxidized into defensive p-benzoquinones in tiny extracellular compartments lined with cuticule.G. M. Happ (1969). Multiple sex pheromones of the mealworm beetle, Tenebrio molitor L. Nature 222: 180-181.
Sex-specific pheromones of male and female beetles attract the opposite sex. A male antiaphrodisiac inhibits the responses of other males to female scent.G. M. Happ, C. M. Happ, & S. J. Barras (1971). Fine structure of the prothoracic mycangium, a chamber for the culture of symbiotic fungi in the southern pine beetle, Dendroctonus frontalis. Tissue and Cell 3: 295-308.
Two species of fungal pathogens that kill trees simultaneously nourish beetle larvae. The fungi infect new trees because the adult beetles are vectors, harboring only the two pathogens in a cuticular pocket that is analogous to micro Petri plate.N. M. Gadzama & G. M. Happ (1974). The structure and evacuation of the spermatophore of Tenebrio molitor L. (Coleoptera: Tenebrionidae). Tissue and Cell 6: 95-108.
The spermatophore is a multilayered sperm package. Once inserted into the female reproductive tract, it undergoes programmed expansions and bursts to liberate semen.D. C. Kelly, M. D. Ayres, T. Lescott, J. S. Robertson, & G. M. Happ (1979). A small iridescent virus (type 29) isolated from Tenebrio molitor: a comparison of its proteins and antigens with six other iridescent viruses. J. Gen. Virol. 42: 95-105.
P. J. Dailey, N. M. Gadzama, & G. M. Happ (1980). Cytodifferentiation in the accessory gland of Tenebrio molitor. VI. A congruent map of cells and their secretions in the layered elastic product of the male bean-shaped gland. J. Morphol. 166: 289-322.
Semisolid secretions from eight cell types in the bean-shaped gland are molded into the layers of the spermatophore within the male tract.H. Shinbo, T. Yaginuma, and G. M. Happ (1987). Purification and characterization of a proline-rich secretory protein of an insect spermatophore. J. Biol. Chem. 262: 4794-4799.
The 23kd spermatophorin is isolated, characterized, and traced from its cell-type of origin to a specific layer of the spermatophore.T. Yaginuma, H. Kai, and G. M. Happ (1988). 20-Hydroxyecdysone accelerates the flow of cells into the G1 phase and the S phase in a male accessory gland of a mealworm pupa (Tenebrio molitor) . Develop. Biol. 126: 173-181.
Cells accumulate in G2 during the early pupal stage. The major surge in molting hormone releases the pupal G2 block and leads to adult differentiation.G. C. Paesen and G. M. Happ (1995). The B proteins secreted by the tubular accessory sex glands of the male mealworm beetle, Tenebrio molitor, have sequence similarity to moth pheromone-binding proteins. Insect Biochem. Mol. Biol. 25:401-408.
The soluble secretions from tubular accessory glands contribute to the seminal fluids in the spermatophore. Alpha-helical B glycoproteins in semen appear to be carriers for lipid ligands.L. J. Kennedy, H. J. Huson, J.B. Leonard, J. M. Angles, L. E. Fox, J. W. Wojciechowski, C. Yuncker, G. M. Happ (2006). Association of hypothyroid disease in Doberman Pinscher dogs with a rare major histocompatibility complex DLA class II haplotype. Tissue Antigens. 67:53-56
J. A. Runstadler, G. M. Happ, R. D. Slemons, Z.-M. Sheng, N. Gundlach, M. Petrula, D. Senne, J. Nolting, D. L. Evers, A. Modrell, H. Huson, S. Hills, T. Rothe, T. Marr, and J. K. Taubenberger (2007). Using RRT-PCR analysis and virus isolation to determine the prevalence of avian influenza virus infections in ducks at Minto Flats State Game Refuge, Alaska during August 2005. Archives of Virology 152:1901-1910.
Subtype diversity in a natural viral "hotspot".A. Read, S. J. Vogl, K. Hueffer, L. A. Gallagher, G. M. Happ (2008). Francisella genes required for replication in mosquito cells. J. Med. Entomol. 45:1108-1116
Genes of the Francisella pathogenicity island are required for growth in Sua1B cells, a hemocyte-like cell line derived from Anopheles gambiae.
Last modified: 22July2009