Mechanisms of Rapid and Winter Cold-hardening in Insects (IBN #0416720)
Richard E. Lee, Jr. and David L. Denlinger, Principal Investigators
Ongoing collaborative research between investigators at Miami University and Ohio State University will focus on molecular and physiological adaptations used by insects for surviving low temperature. Specifically this work will compare two distinct responses, termed rapid cold hardening and winter cold hardening. The first is an extremely swift physiological response that occurs within minutes to hours after mild chilling. This response protects against chilling injury as occurs during daily cycles of cooling and warming in summer. This rapid cold-hardening response is ecologically important because it allows insects to continuously fine-tune their physiological function and organismal performance to match even modest changes in environmental temperature that occur commonly throughout much of the year. In contrast, winter cold-hardening allows insects to survive extreme and extended periods of cold. Although rapid cold-hardening occurs in a wide range of insects and related animals, little is known about the physiological mechanisms underpinning this response. Recent, pilot studies identified two potentially important mechanisms, membrane fluidity and stress proteins (heat shock proteins), that contribute to this protective response. This research program will use a model insect, the flesh fly Sarcophaga crassipalpis, to clarify the roles of these mechanisms in rapid cold-hardening and winter cold hardening. The results of these studies will provide a more comprehensive understanding of the integrated physiological events that both enhance cold tolerance and allow insects to adjust their physiological performance to match changes in environmental temperature. This research may also provide new strategies and tools for disruption of insect populations and for the long-term storage of insects and other organisms at low temperature. In addition, this project will impact significantly the infrastructure for scientific research and education in multiple ways. Graduate students and postdoctoral scholars as well as undergraduate students will have the opportunity for extended research experiences that will include publication of scientific papers and presentations at national meetings. As has been done previously, minority high school students will also gain research experience each summer through an internship program. In addition to these traditional duties, the investigators anticipate continuing to integrate their research into more nontraditional teaching opportunities such as: providing in-service professional development programs for K-12 teachers, publishing articles in teacher education journals, developing an insect cold tolerance laboratory for university biology students (an introductory biology laboratory based on this research is planned with a target audience of 8,500 students/yr), and by giving presentations to professional societies, producer groups, and lay audiences.
