COURSES TAUGHT

BMS 290 - Human Physiology
BMS 291 - Lab in Human Physiology
BMS 301 - Introduction to Research
BMS 508 - Advanced Human Physiology
BMS 601 - Experimental Design

EDUCATION

Ph.D. (Genetics) University of Iowa, Iowa City, IA, 1987
B.A. (Biology and Chemistry) Hope College, Holland, MI, 1980

RESEARCH INTERESTS

My research focus is on the identification of processes that may be affected by the neurotransmitter histamine, in the fruit fly Drosophila melanogaster. One gene known to be necessary for communication between cells encodes the enzyme that synthesizes histamine, Histidine decarboxylase (Hdc). We are currently examining the role of the Hdc gene in establishing when and where the neurotransmitter substance, histamine, is synthesized.  We are also continuing to examine what the function of histamine may be regarding central brain function and its consequences of behavior.  As a result, projects in my lab range from molecular biology projects to behavioral neuroscience projects.

Current Research Projects include:

1) Analysis of developmental and tissue-specific regulatory regions of the Hdc gene. Transgenic flies that contain a gene fusion between the upstream portion of Hdc (pHdc) and the enhanced green fluorescent protein (eGFP) have been generated to examine the expression control of the Hdc gene. We have determined that the upstream promoter region for the Hdc gene does induce eGFP expression in most histaminergic cells. Work investigating which cells throughout development are being marked with eGFP could be done. We are now beginning to construct new transgenic flies, some of which will have an altered Hdc promoter region that will enable a more exciting manipulation of histamine-containing cells in the fly’s brain.

2) Determining the contribution of central brain histamine to behavior. We have identified an effect that a central nervous system histamine deficiency has on courtship behavior in flies. We will continue examining these effects, using engineered Hdc genes in transgenic flies. We are also investigating a number of other behaviors to determine the contribution of histamine towards those behaviors as well. One of the more recent projects involve examining the effect of histamine on spontaneous activity demonstrated in decapitated flies.

3) Histamine and gut function. We have also identified histamine in specific regions of a new tissue, the fly gut, suggesting there may be some function for histamine in gut function. We have recently shown that lack of histamine has an effect on the regulation of gut pH in the larva and adult fly. Currently, students in my lab are examining histamine gut localization with respect to identification of the cell type that may contain histamine in flies that specific cell types can be identified, using confocal fluorescence microscopy.  

4) Histamine function for secondary cells in the male.  We have recently found histamine in a type of cell in the male accessory gland, known as the secondary cell.  These cells have been associated with male-induced female behaviors, resulting from copulation.  We are attempting to localize histamine to these cells using cell-specific markers for secondary calls and are studying the effect of histamine on these behaviors.  Preliminary results do indicate a role for of histamine in several behaviors induced in females after copulation.