My lab focuses on the molecular biology of disease vectoring insects. In particular, many of the projects are associated with the reproductive biology of these insects. This knowledge allows us to understand the biology underlying these medically important insects and develop novel control strategies to prevent transmission of the diseases they vector. Below you will find descriptions of some of the projects underway in the lab.
Regulation of Lactation and Milk Protein Genes in the Tsetse Fly
Tsetse flies are viviparous, meaning that they give birth to live young. During their pregnancy, they nourish their offspring with a milk like secretion. This secretion is produced by a specialized gland termed the milk gland (pictured). This tissue produces tsetse fly specific milk proteins and mixes them with lipids to produce the nutrients required for larval development. The expression of the genes coding for the milk proteins are sex/tissue specific and are tightly regulated by the pregnancy cycle in the female. Our aim is to determine the molecular mechanisms and signals regulating these genes.
The Modulation of Female Tsetse Fly Reproductive Physiology by Male Seminal Secretions
Male seminal fluid proteins regulate important physiological and behavioral changes observed in mated female insects, including reduced receptivity to remating, increased blood meal volume, initiation of ovulation and morphological modifications to the female reproductive tract. Manipulation of the formation of the seminal secretions in males or the post-mating responses in the female has the potential to disrupt tsetse reproduction. The aims of this project will define the physiological, molecular and metabolic responses occurring in the female in response to mating/ seminal secretion transfer as well as identify seminal biochemical compounds and their associated metabolic pathways.
The Role of the Obligate Symbiont Wigglesworthia in Tsetse Reproduction
Insects with restricted diets rely on obligate microbes to fulfil nutritional
requirements essential for biological function. Tsetse flies feed exclusively on vertebrate blood and harbour the obligate endosymbiont Wigglesworthia glossinidia. Without Wigglesworthia, tsetse are unable to reproduce. These symbionts are sheltered within specialized cells (bacteriocytes) that form the midgut-associated bacteriome organ. In this project we use transcriptomic and metabolomic analyses to develop a holistic understanding of the symbiotic dialogue that supports the fitness of the partnership at the molecular and biochemical levels.
The Comparative Genomics of Tsetse Fly Species
The production of the genomes for six tsetse fly species has provided the opportunity to analyze the genomic differences underlying their differences in ecology, host specificity and vectorial capacity. These species (Glossina morsitans, Glossina pallidipes, Glossina austeni, Glossina palpalis, Glossina fuscipes and Glossina brevipalpis) have different host, ecological and vectorial capacity features. We are directing our analyses to identify and characterize genomic features associated with sub-genera and species specific traits.