ACOUSTIC WAVE SENSOR FOR INVESTIGATING THE INFLUENCE OF PLANETARY CONDITIONS ON LIFE PROCESSES SUCH AS GENE TRANSCRIPTION
Christine N. Jayarajah and Michael Thompson
In considering the scientific and technical aspects of Mars exploration and settlement, it is necessary to develop efficient experimental techniques to study the effect of environmental conditions on fundamental biological processes such as gene transcription, expression and cell differentiation. We present the development of an on-line sensor based on the thickness-shear mode (TSM) acoustic wave device for monitoring transcription initiation in order to study the physical and chemical nature of the transcription machinery. In transcription, the enzyme RNA polymerase must not only bind specifically to its promoter DNA sequence, but must also initiate the catalytic process of template dependent RNA synthesis. Environmental cues such as gravity, light and radiation can control transcription of certain genes and transcription factors at the initiation stage. The network analysis of impedance measurements allows for characterization of TSM sensors upon binding of RNA polymerase to template DNA immobilized onto a gold electrode surface. The TSM device offers several advantages in being able to detect a series of events such as adsorption, hybridization and binding on the same sensor surface. Since signaling is direct for the TSM device, no labeling agents are required. In addition, the TSM sensor is capable of supplying multi-dimensional information. Another application of this sensor technology in the context of Mars exploration could be to perform preliminary experiments on samples from Mars or polar regions on Earth that are most 'Mars like'.