RNA signal structures, also known as posttranscriptional regulatory regions, are a combination of sequences and secondary structures of messenger RNAs. They predominantly occur as short stretches of approximatly 5 to several hundred bases in the untranslated regions of the messenger RNA. They are important for posttranscriptional regulatory events during gene expression in all living cells. In this bioinformatic work a database and software system is presented for the storage of molecular and functional data of RNA signal structures. The software and the structure of these data are suitable for their application in the analysis of genomic data for the detection of additional RNA signal structures and the characterization of RNA transcripts. The software and the search engine can be used for a fast sequence homology search as well as for a longer lasting combinatorial search for secondary structure and sequence homology