Grant: Discovery Grants Program - Individual

OVERVIEW. Biological sex determines many aspects of animal development and physiology, including stress survival, body size, and lifespan. In spite of the importance of sex to these traits, sex is often overlooked as an experimental variable. As a result, little is known about how male-female differences in cellular processes, development, physiology and behaviour cause sex differences in survival, body size or lifespan. Sex hormones explain these differences in some animals; yet sex differences also exist in animals without sex hormones, like insects. Our knowledge of how male-female differences cause sex-biased survival or aging in insects is poor. My long-term research goal is to improve our understanding of how sex differences in fundamental biological processes cause sex bias in these complex traits in insects using the fruit fly, Drosophila, as a model. The focus of this proposal is to study the mechanisms underlying sex differences in starvation survival. My lab discovered a single gene, transformer (tra), that creates male-female differences in starvation survival in Drosophila. Tra is known to control female sexual development, behaviour and reproduction; however, our finding defines a totally new role for Tra in survival. We will combine our unique knowledge of Tra's survival effects with existing genetic tools to identify the relevant differences between males and females that influence survival. To do this, we will pursue the following Goals: GOAL 1. Identify the tissues and stage of development in which sex acts to enhance female survival. Our discovery of Tra as a switch between male and female survival provides a powerful tool to unambiguously determine how each tissue and stage of development contributes to sex differences in survival. These studies will allow us to dissect how sexual development and maintenance of sexual identity contribute to male-female differences in survival, and identify tissues that participate in the stress response.GOAL 2. Characterize the genetic and molecular mechanisms underlying sex-biased survival. Tra is an SR protein, and has been shown to regulate alternative splicing. We will determine the molecular mechanism of Tra's effects on survival by identifying its downstream target genes. These studies will provide novel mechanistic insight into an important question in biology how do males and females survive differently?SIGNIFICANCE. This research not only addresses a fundamental question in biology, but it has important agricultural and industrial implications due to male-female differences in survival after pesticide exposure. The knowledge we generate will assist in the development of novel pesticides that equally target males and females. Several industries in Canada (eg. agriculture), will benefit from this knowledge to combat infestations of harmful species such as Drosophila suzukii (soft fruit crops).