Gene Expression in Extreme Environments: Extending Microarray Technology to Understand Life at its Limits.

Nevada System Of Higher Education, Desert Research Institute, Reno NV

Investigators

Abstract

One of the most challenging requirements for the study of life in extreme environments is studying the organisms inhabiting these environments in situ, and understanding the unique aspects of biological life and adaptations required for survival. The Antarctic marine psychrophiles provide an excellent model group of extreme microorganisms for this work, since very little is known about their biological and functional diversity, or specific metabolic adaptations to life at -1.8 degree C. The overall goal of this research is the development of genomic approaches for studying microorganisms sampled directly from extreme environments and thus, circumventing the requirement for cultivation. The objectives of the proposed work are (1) to sequence six large bacterial genomic DNA fragments isolated directly from Antarctic marine psychrophiles; (2) to construct two different types of DNA microarrays designed to identify genes being actively expressed in uncultivated microorganisms living in the sub-zero marine waters of the Antarctic; (3) to optimize specific aspects of microarray technology for use with environmental samples; and 4) to develop a transferable methodology that will be useful for other researchers in accessing gene expression information directly from the natural environment. The proposed study will make use of an Antarctic genomic DNA library comprised of large (40 kb) genomic fragments of planktonic archaeal and bacterial DNA created in earlier studies to develop targeted and shotgun DNA microarrays. The application of DNA microarray technology to studies of life in extreme environments offers an outstanding opportunity for identifying new genes for biotechnological use. Discovering specific adaptations to extreme environments by detecting genes that are uniquely expressed in the natural environment is an ultimate goal of the research.