CNS transcriptome
Total RNA is extracted from one CNS and eye in Hermissenda crassicornis. Library construction starts with total RNA reverse transcribed to cDNA with an oligo dT primer, with second strand then generated. The cDNA is digested with a restriction enzyme then adaptors ligated onto the double-stranded (ds) DNA.  The adaptor ligated cDNA fragments are the amplified by PCR. This product is purified and processed for emPCR and 454 sequencing according to manufactures procedures.