Deep sequencing identifies regulated small RNAs in Dugesia japonica.

MicroRNAs (miRNAs), which are 18 ~ 24 nucleotides length, play important roles in regulating the expression of gene at the post-transcription level. Dugesia japonica is a branch of planarian organism. It is a model organism for studying the role of miRNAs in stem cell function. Next generation sequencing technology was used to identify the miRNAs of D. japonica. Bioinformatic analysis showed that 262 miRNA and miRNA* sequences were discovered, of which 102 miRNAs were the same as Schmidtea mediterranea and 160 miRNAs were related to other animals. There were 21 miRNAs expressed differentially after amputation. Results also revealed that some key miRNAs might play essential roles in the regeneration progress and some miRNAs might take part in the regulation progress of polarity regeneration in D. japonica.