Mechanisms of sensory control of developmental rate

Northwestern University, Evanston IL

Investigators

Abstract

Social interactions among members of the same species are important in the lives of animals. Whereas it has long been known that these signals could alter behavior, the effects on physiology and development are less well understood. This project focuses on a particular chemical signal that is produced by males of a nematode Caenorhabditis elegans and has the effect of speeding up development of hermaphrodites. Similar phenomenon has been previously described in mammals, whereby unknown signals produced by males accelerate development and maturation of females. The implication is that male-induced acceleration of female development may be a feature found in multiple animal species. Leveraging the strengths of C. elegans as a model system, this project will investigate the mechanisms by which this newly-discovered chemical signal alters the progression of development. The focus will be on identifying specific developmental processes that accelerate, how acceleration is coordinated among different organ systems, and how the signal is sensed by the recipients. The proposed experiments, which primarily involve C. elegans, are expected to offer insights into how the rate of development is controlled and how social signals alter development in other species, possibly including mammals. Through engagement with high school science teachers and students, the investigators aim to increase participation of individuals from communities currently underrepresented in STEM fields. Additional activities are planned to disseminate results of the project to the broader public. Various environmental conditions can alter the orderly unfolding of developmental programs in animals. One of the less understood sources of signals that could affect development are social interactions among conspecifics. The goal of this project is to investigate the mechanisms by which one such signal alters the rate of development. Specifically, C. elegans males were found to produce a diffusible compound(s) that accelerates larval development in hermaphrodites. This project will explore the mechanisms of this phenomenon along three broad Objectives. First, to define which aspects of development are accelerated, to understand how acceleration is coordinated, and to assess organismal consequences of this developmental acceleration. Second, to investigate the roles of the heterochronic pathway and transcription factors in regulating the acceleration. Third, to elucidate the mechanisms required for sensing the signal by the recipients. In addition to improving the understanding of how social signals affect developmental plasticity, this project is expected to contribute to the knowledge of general mechanisms that control the tempo of development. Broader Impact activities will improve STEM education and promote diversity. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.