Beroe cucumis transcriptome

The ctenophore Beroe (class Nuda) is a very common but enigmatic marine organism possible representing in its organization one of the most basal Metazoan lineages. Ctenophores are the earliest extant group with “true” neuronal and muscular tissues. Thus, it is one of emerging models to study the evolution of animal organization and the origin of nervous and muscular systems in particular. However, nothing is known about the molecular organization of this organism. Here, using pyrosequencing approach we initiated transcriptome analysis of Beroe. Specifically, we developed a reduced representation sequencing method that can detect low abundant transcripts. Our method greatly reduces the amount of sequencing with more accurate quantification. Basically, sequential addition of adaptors paired with controlled digestion of cDNA generates a one transcript on read type of analysis. Combined 5’ with 3’ targeted libraries produces greater coverage of individual transcripts and high quality assembly. Our initial analysis allowed us to identify more than 2,000 of novel transcripts including many components of signal transduction pathways and transcription factors. These developed molecular resources provide critical information for future analysis of the origin and evolution of animal tissues.