Thomas Robert Cech (1947- present) was awarded half of the 1989 Nobel Prize in Chemistry for his discovery of catalytic properties of RNA. While studying the splicing of RNA in the unicellular organism Tetrahymena thermophila, he found that an unprocessed RNA molecule could splice itself. Separately from fellow Nobel Prize winner Sidney Altman, he showed that RNA molecules are not simply passive carriers of genetic information, but rather that they can also take on an enzymatic role in which they catalyze intracellular chemical reactions. This property was originally only attributed to proteins. Cech also studied the structure and function of telomeres, regions of highly repetitive DNA at the end of chromosomes.