Structural Insights into tRNA via Hypochromism

Categorizing the various levels of protein and nucleic acid structures is a relatively straightforward concept students understand quickly when shown representative structural images. However, keeping in mind the idea of primary, secondary, and tertiary structure proves more difficult when students are in the laboratory setting simply looking at a clear solution containing tRNA. Here, a laboratory exercise is described comparing A260 values from tRNA samples containing structural elements to samples where all structure has been abolished through the use of alkaline base hydrolysis. The amount of hypochromism resulting from structural features in tRNA is used to highlight the different levels of structure formed in the absence and presence of magnesium cations.