Abstract
Some RNAs derived from plants involved in immune processes such as immune regulating functions and antiviral activities have heat-resistant properties, and tea (Camellia sinensis)-derived RNAs are one example. We examined the mechanism of heat stability of RNAs from tea infusions. Heat-resistant tea RNAs were found to be circular RNAs with guanine-cytosine contents of approximately 60%. The ratios of guanine/cytosine and adenine/uracil were 1.01 and 0.95, respectively. It is likely that these tea circular RNAs have higher-order structures such as a rod-like structures, because they were unstable to heat in the presence of urea.
