Computational identification of microRNAs and their targets in wheat (Triticum aestivum L.)

microRNAs (miRNAs) are a class of endogenous, non-coding, short (approximately 21 nt) RNAs directly involved in regulating gene expression at the post-transcriptional level. Previous reports have noted that plant miRNAs in the plant kingdom are highly conserved, which provides the foundation for identification of conserved miRNAs in other plant species through homology alignment. Conserved miRNAs in wheat are identified using EST (Expressed Sequence Tags) and GSS analysis. All previously known miRNAs in other plant species were blasted against wheat EST and GSS sequences to select novel miRNAs in wheat by a series of filtering criteria. From a total of 37 conserved miRNAs belonging to 18 miRNA families 10 conserved miRNAs comprising 4 families were reported in wheat. MiR395 is found to be a special family, because three members belonging to the same miR395 family are clustered together, similar to animal miRNAs. MiRNA targets are transcription factors involved in wheat growth and development, metabolism,and stress responses.