Induction of Plant Allergens by Environmental AgentsEPA Grant Number: R830399
Title: Induction of Plant Allergens by Environmental Agents
Investigators: Goldblum, Randall M. , Brooks, Edward , Midoro-Horiuti, Terumi , Postlethwait, Ed
Institution: The University of Texas at Austin
EPA Project Officer: Carleton, James N
Project Period: December 1, 2002 through November 30, 2005
Project Amount: $250,000
RFA: Futures Research in Natural Sciences (2001) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Hazardous Waste/Remediation , Land and Waste Management
The overall goal of this proposal is to describe an emerging field of knowledge and show how it may be applied to an environmental problem in a unique way. The problem that will be investigated is the increasing prevalence of allergic disease, including asthma, which has occurred over the last two decades in developed countries. The innovative concept that forms the basis for this project is that changes in environmental conditions can indirectly influence allergic diseases by inducing plants to increase their production of allergens. Thus, the hypothesis that will be tested in this project is that anthropogenic changes in the local environment of plants can enhance their production of some allergenic proteins. These changes in plants may potentiate human sensitization and allergic manifestations. The expression of one of the major allergens, Jun a 3, by mountain cedar trees will be the model system for this investigation. The three specific objectives are to: 1) identify up to three environmental exposures that induce Jun a 3 expression in mountain cedar seedlings and/or pollen in the lab; 2) compare the production of Jun a 3 by trees exposed to higher and lower levels of pollutants in their natural environment; and 3) correlate the production of Jun a 3 in leaves with that in pollen.
In order to test our hypothesis, a two-phase approach will be taken. First, we will test the response of growing mountain cedar seedlings and viable pollen grains to several potential environmental stimuli under controlled conditions in our specialized Inhalation Exposure Facility. This will allow us to identify a small number of environmental factors that can induce Jun a 3 responses and the dose and time course of these responses. In the second phase, we will confirm that the responses seen in seedlings occur in adult trees, growing in regions of high pollution by examining the Jun a 3 expression in the leaves and pollen and comparing them to those from trees grown in areas of low pollution.
Based on our preliminary results, we anticipate that repeated exposure to moderate levels of ozone and exposures to some wavelengths of UV irradiation will induce the expression of Jun a 3 in mountain cedar seedlings. Thus, we anticipate that cedar trees growing in areas heavily polluted with oxidant compounds and regions with excess UV irradiation, secondary to depletion of stratospheric ozone, will produce more of the allergen Jun a 3. The primary benefit of completing this project will be to open up a new field of investigation related to indirect mechanisms by which changes in our environment may impact allergic diseases, including asthma. Practical responses include removal of responsive, male trees from polluted areas. In the long term, developing recombinant trees that do not produce allergens would be an option. In addition, once the response pattern for environmentally-inducible plant genes have been characterized, harnessing the promoters of these genes will allow the development of trees that produce visible signals when exposed to dangerous pollutants. Such plants could broaden and intensify our current approaches to environmental monitoring.