Studies on tRNA Structure Using Covalently and Noncovalently Bound Fluorescent Dyes

Abstract

For the past few years, we have been interested in developing techniques which can provide information about the tertiary structure of nucleic acids in solution. The use of fluorescent labels would appear at this time to be an advantageous approach because of the large variety of detailed information which could be obtained from a single set of measurements (Stryer, 1968). Fluorescent dyes can be attached to a nucleic acid either covalently or noncovalently. If a single dye is attached to the nucleic acid, fluorescence polarization (Weber, 1966) or decay of fluorescence anisotropy measurements (Tao, 1969) can provide information about the size and shape of the macromolecule and degree of flexibility near the point of attachment of the label (Wahl, Paoletti and Lepecq, 1970). If a dye which is responsive to its environment, such as l-Anilino-8-naphthalenesulfonate (Stryer, 1965; Weber and Laurence, 1954) or ethidium bromide (Lepecq and Paoletti, 1967), is used, considerable information may be gained about the local structure near the point of attachment of the dye. When two or more dyes are present on a nucleic acid molecule, it may be possible to determine the distance between them by energy transfer measurements (Stryer and Haugland, 1967). If the dyes are attached at known points in the primary structure of the nucleic acid, the resulting distance measurements will provide a severe constraint on possible tertiary structures (Beardsley and Cantor, 1970).KeywordsEthidium BromideFluorescence LifetimeRotational Correlation TimeStructural PerturbationAnticodon LoopThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.